Harold Bawlzangya Racing

Yamaha Gas G29 Build

This is what I got for $500.  Had to drive 1.5 hours north to get it.

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The engine was in a couple of boxes:

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The following day I realized I forgot to get the gas tank.  So another 3 hour round trip to get this:

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With the plastics being completely beat-up on the gas cart, it was a no-brainer picking this electric cart up for $80.  This cart was only 45 minutes away.

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It only had 1 front wheel and nothing on the back, so it was a little difficult getting it in the garage:

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Luckily the plastics were in as good as shape as the CL ad, so here is the pile of parts I’m keeping:

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The guy who sold me the gas cart said all the parts for the 357 engine were in several boxes plus he had purchased brand new Yamaha parts to rebuild it.

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Sure enough everything was there to make a complete engine:

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I put this on eBay and CL.  An engine rebuilder wound up buying this from my CL ad for $350.

 


Someone hit something with the front end of this cart.  It appears that the impact was focused on the cross-member. The frame rails don’t have any damage to them.

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The passenger wheel was worn more than the driver side and visually seemed to have too much positive camber.  There is a very good chance that this tire was already heavily worn before every being put on this cart.  But I was concerned that maybe this had something to do with the impact to the front end.

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Everything looked OK, but as soon as I stood on the front end and jumped up an down, I quickly noticed that one of the passenger front shock was frozen in place – it wouldn’t compress or rebound.

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So the electric cart comes to the rescue again.  Electric suspension is now on the gas cart.

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With the front end in better shape, I just want to take some time to make sure the front end wasn’t damaged from that impact.  It has been a while since I’ve had a need to use this digital angle gauge, but it came in handy for this.

Zero’d it out on a cross member:

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Both sides are essentially at the same angles:

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Just for piece of mind, I checked the angles of several other parts of the frame and things seem to be about as straight as I can measure.

With a “newer” front tire on the passenger side, things looked normal.

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Time to move forward . . .


The floor pan from the gas cart had a nice crack where the gas/brake pedal mount:

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I wasn’t optimistic that I could plastic weld that, so once again, the electric cart to the rescue.  With the electric pan in the electric frame, it is time to cut-out the center section to make room for the gas engine:

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I left the cut generous so I could go back later and clean it up:

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So here is the modified electric pan in the gas frame:

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Finally getting around to doing some actual work on the gas cart today.  I wanted to fix this cross-member that was damaged:

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I will be using the cross-member from the electric frame:

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Damaged piece out:

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Removed all traces of the welds:

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Cut the good cross-member out of the electric frame rails and got a nice tight fit to the gas frame:

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My son welded it in:

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Scrap metal now:

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Time to throw away some of the parts I won’t be using.  The gas body is way to beat up to be worth saving:

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Turned into this:

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Center part of the electric floor pan:

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Team clutches and engine shrouds:

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I couldn’t find anything locally and the few that were on eBay were too expensive.  So I drove over to Oxford, Alabama to get a Club Car rear end for $550.

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While I am there I notice they have another rear end that isn’t quite locked up, but there was a lot of resistance when trying to spin the input shaft.  I only brought enough cash with me for the one rear end.  The next day I text the guy and asked if they would be interested in selling the “broken” rear end.  I’m asked to make an offer, so I suggest $200.  He counters with $300 and I turn it down.  The next day I get a text from the owner saying he will take the $200.  So another drive to Oxford and I have this:

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I won’t be using the governor in the Club Car rear end, so I will be removing those parts.  This is what I’ll be using:

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Need to remove the governor pin first:

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Governor arm next:

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Red Loctite will keep that from ever moving:

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Discarded parts:

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First step on getting the Club Car rear end into the Yamaha is to get rid of the mounts:

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Using the Yamaha rear end, I built a quick jig to help align the Club Car rear end.  I used scraps and locked the engine cradle in place:

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Mark the position of the left and right side studs:

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Those marks will be used to align the Club Car studs with the rear end in place.  The Club Car axle aligned based on the reference marks from the Yamaha rear end:

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On to the new mounts.  A 2″ hole saw was the perfect size:

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After triple checking that the Club Car rear end is aligned, welded the new mounts in place:

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Finally the Club Car rear end is sitting in the Yamaha G29:

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OEM parts to fix-up both rear ends:

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6:1 gears arrived:

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Gear on:

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First bearing:

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Second bearing:

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Done with this part:

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Axle tubes are ready for painting:

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First coat on:

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Second coat and done:

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And the spare Club Car rear end finally sold on Craigslist yesterday for $400:

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I need to remove the governor from the Lifan engine:

Removing this:

And this:

I used a plug for the top of the engine:

I couldn’t use the same type of plug on the outside of the cover.  I didn’t feel comfortable using the plug from the inside.  So I used a brass bolt.  I tapped the cover and used red loctight:

That probably would have been good enough, but just to over-kill it, I damaged the threads:

Then I had to go one step further and I put a piece of stainless wire through it:

Making sure to blue loctight the cover bolts.

Worked on replacing the rear axle bearings. I reused the bushings but polished them up:

Pressing the bearing on first:

Then the bushing:

All ready to be installed:

My order from Vegas Carts came in yesterday with the HD clutch and the belt:

 


Now that I’ve got the HD driven clutch, I can see where I’m at.  This is what I get for fabbing and welding things up without all the parts to do a proper test fit.  The regular size driven clutch probably would have fit fine, but this larger HD clutch is hitting the out bracket:

A little work with the grinder and now I see it hits the inner bracket:

Some more grinder work and all is good:

Now to see how it fits in the cart.  With the gas engine cradle in place:

Bolt in the rear end and things fit well.  I won’t be able to remove the driven clutch with the rear end in the cart, but I don’t plan on having to do that very often anyway.  Probably once a year for routine maintenance.

Getting a rough idea of how things will fit with the engine in place:

The gas engine cradle isn’t going to work without some big modifications:

I’m going to make a new engine mount set-up using the electric G29 (that $80 cart just keeps getting to be a better deal all the time) cradle.  This set-up will have forward/back adjustment built into it, so no need to slot the engine mount plate.

Starting with this:

Ready for painting:

Then the bottom part of the clamps:

Ready for painting:

 

I used aircraft stripper to get the powder coating off the electric cradle.  In some areas the powder coat bubbled off within minutes, other spots I had to apply the stripper 4+ times and let it set for 20 minutes each time.  Not sure why there was so much variance.


 

So with the paint drying, time to work on how to mount the starter.  As usual, I like to overbuild things.  This is what I put together:

Installed:

Sandblasted for painting:


The moment of truth, putting it all into the frame for the first time:

Plenty of room around the starter/generator:

Plenty of room in front to get to the valves and carb:

 


Finally a rolling chassis:

 


Getting around to the exhaust.  Using 1″ black pipe.  That thickness should keep things quiet and last a while.

There was no room in the back of the cart for the muffler so it had to go up front.  This seemed like it was going to be the best location.

 


So with the engine/rear end in the cart and the exhaust hooked up, I started the engine for the first time.  I originally just had the muffler hooked up.  It wasn’t too loud, but definitely louder than stock.  I then put on the tail pipe and was amazed at the difference that made.  There was now more noise coming from the motor itself than the exhaust.

But slowly increasing the RPM’s showed a flaw in my engine mount system.  The rubber bushings were allowing the engine to rotate back toward the rear end, thereby changing the distance between the clutches.  So I’m scrapping that system and doing a direct mount.  I will do my best to replicate the set-up that is used in the ’97+ Club Cars.

So here are the problematic bushings:

I also decided to replace the steel mount with 1/2″ aluminum.  Cutting the aluminum to the correct size on the table saw:

I also decided to scrap the steel pieces I made and replace them with stainless.  I couldn’t bring myself to buy a new welding tank or empty the nearly full 75/25 mix I had in my current tank.  I found a company that sells flux core stainless wire.  It was definitely difficult to weld with and the welds are ugly, but it was the cheaper option.  Everything is now stainless:

I couldn’t replicate the Club Car design, but I copied the concept.  The engine is bolted solid to the aluminum mount.  The main stainless bracket is bolted to the engine in 3 areas.  Then the rear end is bolted to the main stainless bracket.  So now the engine, cradle and rear end are all tied to each other.

 


Finally finishing up the exhaust.  My “quick” disconnect connection:

The entire system in place:

Muffler supports in stainless:

I went back and over-killed the support bracket:

Also put a little radius on the inlet side of the tail pipe:

 


Exhaust 2.0 – details of why and how I changed the location of the muffler HERE.

There was so little room in the back end of the cart that this was the only place for the muffler:

All painted up:

 


More disk brake pictures HERE.

I didn’t like the how much this clevis pin moved around in the brake pedal:

So I threaded it:

Blue loc-tight:

And just for the final over-kill, I slotted the nut and added a cotter pin:

All hooked up:

 


Made a new hole for the key on the left and used the original key hole for the USB charger/voltmeter.  Not sure yet how I will fill up the square opening.

I’ve used this stuff for years on my dirt bikes and it has always worked well to keep moisture out.

Some on the kill wire connection:

This is where/how I located the solenoid and voltage regulator.

I welded a nut into the frame so I could use it as a ground point:

Wires grounded with protectant:

Since I don’t have the little sealed electric box like the Club Cars do, I decided to put all my other electrical connections up front under the drink holder.  It will be easy to get to and should stay pretty well protected.  It will be a little while for headlights/taillights, so that circuit will be added later.

Another ground point up front.

All wiring in place:

Cleaned up:


The old tank wasn’t going to fit, so this 4 gallon tank will have to do.

Since this was the same pump I have on the Club Car I was hoping to avoid the return line.  But a few minutes of the engine running made it obvious I would have to install one.

Ran out of hose clamps.

Down near the battery I have a brass barb that connects the two different sized fuel lines.

 


To install the Aussie Speed valve cover, I used stainless steel parts from Amazon.  Red loctite on the threaded rod and snugged it into the head.

The coupling nut was then tightened down.

Viton washer and SS washer.

Finally the SS acorn nut.

The VC adapter didn’t come with a large enought ID fitting.  It is a little tough to see in this picture, but there is a raised rectangular area that is just a little wider than the threaded hole.

I cut down that raised part to get a little more room to make a larger hole.

Got very, very close to the edge.

Fitting installed.

Excess removed.

Grommet and PCV valve installed.

All plumbed up:

 


I was going to use this isolator block that already had a nipple installed.

The problem is that nipple represents the 3rd different size nipple on the cart (fuel pump and carb are the other two).  To try to stick with just two, I went to all the local auto parts and hardware stores looking for a different solution.  All of the fittings I could find had threaded bases that were so large it would leave very little plastic left on the isolator.   Thin plastic and the pipe taper threads would surely result in cracked plastic.

So I thought I would make my own fitting.  I started with this dual ended barbed fitting:

I first tried to thread one end as is.  The largest OD part of the barbs threaded well, but the thinnest OD part of the barb didn’t have any threads.  I’m sure I could have used it as is, but I would really have threads cut all the way down.  I have soldered brass before, so I thought I would try filling in the low spots and try to make a more consistent diameter.

This is what I used.  It wasn’t pretty as the solder would drip, but as easy as brass cuts, the solder was even eaiser.

Some of the threads on the soldered areas aren’t perfect, but it will work well enough for this.  This is tapped with 5/8-24 threads.  These are regular threads (not pipe taper) so no concerns about splitting/cracking the plastic.  I drilled the hole in the isolator off center where I had more plastic to tap.

I put some black RTV on the threads and all set.

 


Two comparison photos:


Vegas Carts used to make an adapter to connect the clone carb to the OEM/stock Club Car airbox.  I had been holding off on buying one, thinking there was no hurry.  When I finally decided to get it, it appears I was a month late as Vegas Carts has stopped making/selling them.

So I thought I would see if I could make their 32mm Billet adapter work.  What I needed was an adapter that would mate the 32mm adapter to the front of the carb.  I drilled the two holes for the carb studs and then traced the two different gaskets on each side.  This is a piece of 1/2″ aluminum plate.

I set my hand router to a little over 1/4″ depth of cut and then slowly started routing out the material.  Here is the carb side:

Once both halves were routed, I was left with the sharp edges that represented the differences of the two sides:

Some rough blending with the dremel:

And then cut it out:

All cleaned up:

This is where it is installed:

The last thing I needed to do was modify the 32mm intake.  This was made to fit against the cylinder head where the studs are a larger diameter.  Since I am using this out at the end of the studs where they are smaller in diameter, I have this problem:

I popped out one of the metal spacers from the stock air assembly, cut it down and fit it into the adapter:

Installed:


Made this out of 3/8″ stainless:

In goes on between the carb and isolator:

I’ve made so many custom changes that I try to keep as much stock as possible.  In order to use the stock throttle cable, I had to bend a piece of stainless steel wire to connect the cable to the carb:

The return springs hooks onto the wire:

And then the cable connects to the wire:

All hooked up:

 


Checked all the critical items to make sure I didn’t forget to tighten something down.  Still a lot of work to do, but this is the closest I have had the cart to running condition and I had to get it out on the street.  Ready to get out of the backyard:

It was a very uncomfortable drive around the neighborhood, but all went well.  I didn’t drive too hard or fast, but I was very happy that I was cruising around at 20mph at just 2000 rpm.  The fastest I got it was 30mph, I didn’t see what the RPM was at.

First time in the driveway since I brought the cart home last December.


This is the tailpipe I’m using.  I will create a better mount for the end once I get the body on.

Adding this gives a 10dB reduction, which is 1/2 the perceived loudness.

At idle:

At 2000 rpm:


The two thin fender washers that came with the clutch haven’t held up well to removing/installing the clutch just a couple of times now:

I used some of the 3/8″ stainless and made a washer:


I don’t know why it took so long to hit me – but the clone/Lifan engine is really loud.  I took my phone app and pulled the stock Club Car next to my cart for some side by side comparisons.  At idle the Club Car was 5dB quieter, which is about 50% less in perceived noise levels.  As I revved the Club Car to 2000rpm, it gradually got louder.  When I did the same with the clone engine, it was a night and day difference.  It went from about 85dB to nearly 100dB at 2000 rpm.  That just isn’t going to work.

Here is the same idle – 2000rpm on the Club Car:

I started researching how I can make this thing quieter and long story short, I found a brand new Honda GX390 for sale about an hour north of me.  I took the drive and sure enough it was brand new.  Brought it home and most everything swapped directly over.  I did have to modify a few things due to differences between the Lifan 390 and the Honda 390.

When I was removing the governor, I added a cap instead of a plug for a future modification.

Ready for the Honda:

All bolted in place:

I am pleased and relived to report that the Honda is about 1dB quieter at idle and about 1 dB louder at 2000rpm than the Club Car.


Took the cart out for the first time with the new GX390.  I took it easy since it is a new engine, never really got over 2100 rpm, but that was good for 20mph.  About 1/2 way through riding around I thought I should pull over and check things over.  That is when I discovered I lost my tailpipe.

I started backtracking and found it in the gutter.  I need to remember to hose clamp that thing on next time.


I finally got the body on (temporarily) so I could ride around on a comfortable seat instead of a 2″ wide piece of steel.  Two observations – this cart is quiet and goes really fast!


As I have been driving around to break in the engine, I started having fuel delivery problems.  After looking at a few things, it finally hit me that my return line was too free flowing.  The fuel line is much longer, has a fuel filter in-line and it goes down a size to be able to connect to the carb.  The fuel was taking the path of least resistance and at higher speeds, all the fuel was going through the return line and none was making it to the carb.

I got a barbed brass connector and filled one end with solder.  On my second try I got the diameter of the hole sized properly.

About 1.25 hours of driving and no problems yet.


A little heat gun clean-up.


Today looks like it will be the last really nice day for a while – near 80 degrees and no rain.

I bolted on the rear bumper and finished securing the body down.  I added the city stickers to the sides so I would be legal.   Took a ride to Home Depot to pickup some screws to secure the cup holder to the dash.


Turns out the weather man was wrong and today was another great day.  I decided to take a long drive to Walmart and get oil for an oil change.  Still need to put the side panels on the cart.

Almost 15 miles round trip and a top speed for the drive of 33mph.


I’ve made some modifications to the Keihin carb that came on the Honda.  The Keihin is the same as the clone carbs, the fuel line needs to come in from the top.  And it is a smaller diameter than the other fuel lines I’m using. This is how I the fuel line had been run to the carb:

Replaced this:

With this 1/16 npt elbow that is pointed down:

With using the Club Car airbox, I don’t need the choke.  So I’ll plug that hole with a 1/8 npt fitting:

I sanded down the excess that was protruding into the carb:

Installing the $10 eBay adjustable main jet:

While I had the carb all apart, I enlarged the idle jet and opened up one of the 4 holes (furthest one back) that are part of the idle circuit.  Carb installed with 1/4 fuel line running directly to the carb:

I’ll be throwing away the smaller fuel line now.


I finally got around to getting the shifter set-up.  The first problem was the arm on the rear end was too long and hit the body.

That was easy enough to cut down.  I was able to use the bracket on the rear end, I just had to make some adjustments on it.

Then I had to add an extension on to the Yamaha shifter assembly to get the cable to work properly. I also took that as an opportunity to add a little bracket so I could mount the disc brake reservoir.  That was easier than welding a bracket to the frame.

I’m using the electric body, so I’ll need to make a cover plate later on.

I can finally install this cover.  I just need to get more body plugs.


I bought some 3/16″ stainless plate and 2″ square tubing back in November to make a custom engine cradle/swingarm.

I was going to build this over the winter but never got around to it.  I finally started this project this week.  The weather was all over the place – day 1 & 2 I was wearing shorts and a t-shirt and the AC was on.  Day 3 & 4 it was jeans and a jacket with the heat back on.  On the last day – day 5 – it was back to shorts and a t-shirt.

After triple checking my numbers, I started with these cuts:

Then on to the proper positioning of the cross-member:

One of the key items I needed to incorporate into this was an “anti-wrap” feature or bracing to keep the rear end from wanting to twist under acceleration.  This is the final product:

Last test fitting before putting it in the cart:

In and everything looks and lines up well.


I left this oversize as I still need to finalize how I will mount the engine plate to the engine cradle.

I am going to be making custom isolation mounts out of this urethane:


The cross-member that I built into my cradle was exactly in the way of my old exhaust.  So I needed to make a new mounting bracket and I did away with the short 90 degree pieces.

Mounting plate installed:

Engine installed without the exhaust:

Exhaust installed:


I made my own isolator mounts and the turned out well.  The problem was that the 60 duro urethane was just too stiff.

I bought the VC isolators (left) and they did an OK job, but still were on the firm side.  I went to McMaster Carr and picked up some softer mounts (right).  The softer mounts did an outstanding job of keeping the vibrations away from the rest of the cart.

The next issue was dealing with engine moving back toward the rear end during acceleration.  Even with the stiffer VC mounts the engine moved back.  And with the softer mounts it was even worse.  I thought about doing the torque strap/cable that Yamaha uses but found a use for the VC isolater mount afterall.

This is what the cradle and engine mount plate look like:

The engine doesn’t move back while keeping the vibrations to the rest of the cart to a minimum.


Best modification yet!  Engine adjustments are now just a one-handed job.  This is the front and the rear is similar, but tied into the S/G bracket.


No way was I going to be able to change the oil from the front and the rear is even tighter.

That will do it.


I had to run a bypass on the fuel pump supply line, otherwise the the carb would overflow.

When I built the SS cradle, I designed it so that the engine would sit lower.  With my original set-up, the top of the S/G was closer to the bottom of the seat than I would have liked.

Now that the engine is sitting lower in the cradle, I was able to put together an idea I had a while ago.  I found a small moped gas tank that I spliced into the return line from the fuel pump supply and the tank.  I mounted it as high up as I could place it.  Now the carb is being gravity fed and when the fuel hits a certain level in the small tank, it overflows back into the big tank.

The bypass was working fine, so why go through the extra effort?  The cool part of this is that if my fuel pump ever fails, I can still drive home.  All I have to do is pressurize the tank and fuel will fill up the small reserve tank.  I have to remove the gas cap (it is vented) and hold my hand over the opening.  Then if I pull the return line from the reserve tank and blow into it, the pressure forces gas into the reserve tank.  Not sure how many miles I can go with that amount of gas before I have to do it all over again, but it beats being stuck.

This is what it looks like with the body installed.

I have put 50-60 miles on this set-up and it works perfectly.


I couldn’t wait to complete my adapter, so as soon as it was usable, I got this PZ30 carb bolted on.

The only way I could even get it running at anything close to resembling an idle speed was to have the choke fully closed.  And yes, that is a piece of wire that I’m using as a throttle cable.

Using the smallest micro drill I have, I opened up the pilot jet.

I could now get it closer to idle speed without the choke.  It was still faster than I would like and the slide is just about fully closed.  I need to go back in and open it up some more.

 

I got things hooked up enough to where I could take it for a quick drive.

Once I get into the range of the needle, the carb works great.  This carb is much more responsive than the Keihin generator style carb.  The needle is currently in the 2nd richest clip setting.  I think WOT is a little lean, but I want to get everything else cleaned up first.  If WOT is lean, getting the pilot dialed in will help with that.


I have spent a good bit of time dialing in the jetting and am now committed to using this carb.

I cleaned up my adapter plates and this is what I ended up with.

This half goes on first:

Then the other half:

Then finally the carb:

I am going to work on a different type of air box set-up and intake in a little bit.

I wound up using a go-kart throttle cable.  I had to cut it down and put a new stop on the end.  I did this before with my dirt bike carbs.  Drilling a hole in a piece of aluminum keeps the silver solder from sticking a forms a pretty decent stop.

This is what the stop looks like in the slide.


The go-kart throttle cable had the right type of end fitting, but the ID was too large. The stock Yamaha cable is on top and the pin would essentially slide through the ID opening of the go-kart cable.  For the first time in a long while, I didn’t need to go to the store to pick-up something to solve a problem.  I had a bronze bushing in a spare parts container that would work perfectly.

I had to drill out the go-kart fitting one size to get the bronze bushing to fit.

It is obviously too long, so after a little grinding it is finally all put together.


I needed gas for the cart, so I went for a 5 mile drive to fill-up and test out the new carb.

The Keihin generator carb was a big improvement over the clone generator carb. And this slide PZ30 carb is a nice improvement over the Keihin.  Idle and mid-range throttle response is better than with the Keihin.  No surprise there since the generator carbs weren’t designed to operate over a wide range of throttle openings.  At 20 mph (speed limit on the paths) the engine is operating at 2900 RPM’s.  I will do a MPG check once I get everything finalized with the new carb.

In town, the two biggest complaints of the gas golf carts are noise and smell.  I’ve done some scientific smell testing at different times by driving back and forth through some of the tunnels here.  With this new carb, I think there is a big improvement in part-throttle jetting.  I had to go through the same tunnel 3 times before I could really smell any of the exhaust.  And even then it was pretty subtle.  The spark plug confirms that the engine is running well at part throttle openings.  The picture shows the porcelain a little darker than what it really is.  Most of the time on this plug was between idle and 3,000 RPM.

Full throttle is another story.  I am going to pull the carb and go up one size on the main jet.  My 0-30 time wasn’t bad today.

It was a couple of seconds off from my best time with the Keihin carb, but there are two factors that are different.  My best time was done back in November when it was cooler (it was near 90 degrees when I did today’s run) and I was using a different belt that was wider back then.  That wider belt sat higher out of the driven clutch giving me better off the line performance.

Back in November I dropped seconds off my 0-30 times by adjusting the main jet richer and richer each run.  By the time I was at my best times, I was definitely running an overly rich jetting.  I will go up one size on the main and see what happens.


I was wanting to use a light bar instead of the headlights designed for the G29 body.  There was a space between the bumper and front cowl that was just to narrow for the light bar I bought.  The easiest solution was to lower the bumper.  This is what the bumper brackets look like:

For each bracket, only half is used.  I made sure I cut and welded the correct half.  Here is the difference:

I cut-off the half that isn’t used and then painted them up:

I made some brackets out of stainless steel and here is the light bar installed on the bumper:

And on the cart:


I’ve finally got this chinese copy PZ30 carb dialed in.  Got my best 0-30 mph run yet.

I messed around with different main jets and needle clip settings. It looks like the 120 main and 3rd clip from the top needle jet is the way to go.  Now I will take the micro drill best set and find out what the 120 main is equivalent to. That way I can reproduce it.


I cut down a plastic coffee container so it would fit under the engine cradle.  I knew the patio under the deck was sloped, so I backed the cart up under the deck.  I removed the cap from the dranz-it set the coffee container under it.  I did some other things and came back with the jack and lifted the rear of the cart 3-5 inches.  No more oil came out, so I now have a good spot to to all my future oil changes without any additional equipment.

A few ounces of the good stuff and I’m back in business.


I was only able to stay out for an hour as a big storm was coming in.  One thing I forgot to bring were some clear glasses.  With no windshield, I got a few bugs in my eyes.  I bought 2 LED light strips that I was going to try to incorporate on each side of the bumper.  But I decided to take the easy way out and put one on the back of the basket.  I verified that I have that LED strip wired up as a running light.  It is brighter than I would like.  Down the road I may try to find one that is dimmer.


I thought I had the original PZ30 carb working pretty well.  I wanted to experiment with a few things so I spent $23 and got another one from Amazon.  There were a few areas where this new carb looked to be better made.  At least this manufacturer (right) is making an attempt to look like an original:

I put in the new carb and it was in fact better.  I was able to use a smaller pilot jet and my idle is now a steady 950 RPM.  Plug looks good as well.

I quickly bought another one before Amazon ran out of the ones made by that particular manufacturer.


I have been collecting parts to add an oil filter to the engine for quite some time.  Winter and then building the stainless steel swingarm/cradle this spring put this project on the back burner.  Then came the PZ30 carb.  I finally decided to commit to adding an oil filter to the GX390 engine.  It also helped that I found the pump I had been wanting on sale.

I decided that I was going to pull the oil from both the front and rear oil drains.  That way oil would feed the pump no matter if I was going up or down hill.  I also figured I would pump the oil out for oil changes, so no need for a drain.

I considered returning the oil back to the engine through the valve cover.  But the more I read about the design of these engines, I opted not to go that route.  I never found anything that identified lack of lubrication to the valve train as being a weak point for these engines.  And from what I have read, the passage(s) that drain the oil back to the lower end are the same passage(s) that feed oil to the top end.  So my biggest concern was that dumping more oil than the engineers planned for down those passage(s) would interfere with the proper lubrication of the valve train.  Finally, I already had a hole tapped in the top of the block where the governor used to be, so that sealed the deal.

I had removed and installed the engine more times than I wanted to keep track of when I was building the swingarm/cradle.  I got curious how long it actually takes me to remove the engine.  Turns out it is just about 23 minutes.  That included removing the seat back because the basket was in the way of the rear panel access opening.

With the engine on the workbench I could get started.

I also decided to remove the oil sensor while I had the side cover off.  I don’t know why I didn’t do that when I removed the governor when I first got this engine.

Plugged that opening and added the rear drain fitting:

Front oil drain fitting:

And finally the fitting for the oil return:

I wanted to use 3/8″ aluminum fuel line to plumb most of this system.  I thought the aluminum lines would help dissipate the heat as the oil moved through the system.  I was really impressed with myself that I nailed the bends on my first try.

But as I sat back and looked at it, I talked myself out of using the compression fittings and aluminum line.  I figured that even if I tried my best to support the lines, the continuous vibrations would eventually cause a leak in one of the fittings.

So I switched out the compression fittings to barbed fittings for rubber lines.  At this point I was still planning on having lines run from both the front and back drain plugs.  I used some clear tubing and connected the front and back to a T fitting.  I experimented a little with tilting the engine up and and down to see how far I could tilt the engine before I got air in the line.  It turns out that I could tilt the engine up to a 24 degree angle and still pull oil through the fitting.

24 degrees is right at the point that oil is still in the tube:

I didn’t think I would be able to tilt it that far and still pull oil, so I made the final revision to the system to just use the front drain fitting and plug the rear drain.  Pulling the oil from just the front will simplify things and will be one less place for a leak to occur.

This is the pump I will be using.  It uses about 3 amps, is rated for continuous duty and is self priming up to about 3 feet.  I got lucky and caught this on sale. It wasn’t that much more than the cheap, noisy pumps on eBay and Amazon.

I wanted to mount it below the oil level so it would never have to dry start it.  There was really only one place for me to put the pump and pull that off.  Luckily I still had a few pieces of scrap stainless that I was able to weld up a simple mount on the front corner of the engine cradle/swingarm.

Side view:

Top view.  The engine is about as far forward as it will ever need to be, but just to be on the safe side, I positioned the pump so I could still slide the engine forward 1.5 – 2 inches.

It was a lot easier to decide where to mount the oil filter.  I welded on a bracket to the frame here:

And that puts the filter next to the engine with enough clearance to remove and install it with no problems:

Turns out I think my concern about dumping too much oil through the valve cover was valid. This pump moves quite a bit of oil:

 

The last piece I needed was a way to control when the pump runs.  I currently have this timer set to run the pump for 15 seconds every 10 minutes. It is easy enough to change if that combination doesn’t work out.

With the motor off and the seat down, I can’t hear the pump running.  I think I may hook up an indicator light somewhere so I can keep an eye on when it is running.


I finally got two projects that have been on the back burner for a while done.  With those completed, all I have are stainless steel scraps and am just about out of gas.

The first project was making a shroud to better direct the airflow from the fan around and down the cooling fins.  I spent way more time than I thought it would take on this.  It isn’t pretty, but it works really well.  I tired to make the cover fit tight in areas I didn’t want air to escape from.  With the engine running, the air from the fan will blow off leaves off the ground directly under the engine.  Forcing that hot air down, instead of just the area under the seat should help cool things off.

This project went way faster than I expected. I’ve been meaning to cover up with mangled hole where I had to make the electric body fit the gas frame.

Luckily I had one piece of stainless that was just big enough to cover it.  I tapped the 4 holes so I could just thread in 4 SS bolts.

It is kind of hard to tell, but the cut end of each bolt is sitting below the surface of the plate.  That way I can weld them together but grind off the excess.

All done:


I am going to finally cover up this opening in the electric dash:

I am going to try and use as much of my failed shroud as I can.  The first cut is always the hardest:

I am going to get the sensor and magnet mounted first.  I didn’t want to have to drill anything on the Jake’s spindles or weld anything, so I mounted the magnet to one of the bolts holding the disk in place.  I doubt that this extra weight so close to the center of the wheel will cause much of an imbalance.

I made up this bracket that will be bolted in place on the spindle:

And here is where this bracket mounts:

I made a cutout for the base of the computer:

Fits well:

I’m using a strap across the bottom two mounting bolts to hold the base in place:

I didn’t polish the face of the plate, but used some finer sandpaper to get some of the grinding marks out:


Not only was the running light too bright, but with it mounted so high is was almost blinding at night.

With no Radio Shacks nearby, I got this from Amazon for $6.80.

After experimenting with different resistors and different combinations, I settled on two 2K ohm resistors wired in series.

Now I have a running light:


Despite buying my clutch from a reputable place, it is looking like I have a Chinese knock-off.

I noticed a week or two ago that the moveable sheave of my clutch  was wobbling quite a bit.  With the engine off, if I grabbed the sheave at the 9 and 3 o’clock position, I could rock the sheave side to side.  I ordered a new sheave from beltpalace.com along with some different weights and springs to test out.

My back is still sore and I didn’t want push it by pulling the engine out of the cart. So I dropped the swingarm instead:

The first thing I noticed was that the locking plates weren’t bent over on the bolts holding the roller arms in place.

This is how I pulled the spider off the hub.  The 2nd thing that was strange was that I had to use metric M6 bolts to thread into the spider.  Glad I still keep a container full of bolts from the Japanese dirt bikes I’ve owned over the ears.  I thought that Comet was a U.S. company and expected them to use standard threads/bolts.

And this is how sloppy the hub and moveable sheave are:

 

 

The bushings that the guide pins ride in were well worn.  The scary thing is that this clutch has less than 75 hours on it!

So finally on to getting the clutch put back together.  The hub bushing and casting around the bushing were thicker on the new sheave compared to the original:

 

I tried to thread the M6 bolts into the new sheave and they wouldn’t go.  Turns out the new hub is threaded for 1/4″ – 20 threads.  But it wasn’t until I tried to slide the new sheave over the hub that I that it became painfully obvious that this wasn’t going to be an easy project.  The new sheave didn’t come close to sliding over the hub, the ID of the bushing was too small.

So I sat back and tried to figure out what to do.  The evidence certainly pointed to my clutch being a cheap copy – it wore out very quickly, all the threads were metric and the lock tabs weren’t bent over.  I was feeling pretty confident that beltpalace.com was selling OEM parts or at least OEM spec parts.  The springs and weights were all bagged as Comet parts.

And if the new sheave wasn’t made by Comet, it was at least a better copy with standard threads.  I finally decided to make this sheave work.   I doubted I could find a knock-off sheave that would fit my clutch and it wouldn’t be worth it as it would wear out quickly as well.  After about an hour of working on it, I finally got the new sheave to fit over the hub.  I had to run out to the hardware store to get three 1/4″-20 bolts.  And after installing the springs and weights, I made sure to bend over the locking tabs.

I also had to take some material off the sheave so it would slide up high enough and not interfere with the spider.

Now I just need to get the clutch put back on the engine.


 

 

 

 

 

 

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