RUPPSTER- Kohler engine info

#1
Hi everyone. I have a Ruppster buggy that my sons and I are working on. It has a Kohler 2-stroke single cyl engine which I believe to be a K295-1. Engine has electric start. We haven't been able to get any spark so I'm looking for any info. I have checked the points and cleaned them up a bit. Info on these Kohler 2 stroke singles is hard to come by. A wiring diagram for the buggy itself and/or the engine would really help. Of course any other info helps too. I'll try to post up a photo of the engine.

Thanks,

Steve
 
#3
Thanks for the reply!. I looked there, all they have for the Kohler 2 stroke singles is the owner manual, not service manual. They have a service manual for the 2 stroke twins but not singles.

"KOHLER Owners manual covers 2cycle Singles".
 
#5
Update; I found the Kohler service manual as a scanned pdf file at the very edge of the internet, thanks to a hovercraft enthusiast.

http://foxxinabox.com/documents/index.htm
Very cool!! I have a K295 on my Go Joe and also bought a NOS never-been-fired K309 a couple of years ago. I haven't been able to find a decent manual, so THANK YOU! Also, I didn't know Rupp put Kohlers on the Ruppsters. I thought those were all JLOs. Not so? Would like to know more. I'd like to score a Ruppster someday.
 
#7
Very cool!! I have a K295 on my Go Joe and also bought a NOS never-been-fired K309 a couple of years ago. I haven't been able to find a decent manual, so THANK YOU! Also, I didn't know Rupp put Kohlers on the Ruppsters. I thought those were all JLOs. Not so? Would like to know more. I'd like to score a Ruppster someday.
Glad you found it helpful. I'm not even sure that ours is a K295- it could be a 309 or 335, I guess. There is no ID tag and no numbers stamped into it anywhere that I can see. My understanding is that they're all the same except the stroke, so maybe I'll measure the stroke and try to figure out what it is. My son (16) and I are trying to fix this Ruppster and get it in decent condition. I won't say "restore" because we're not going for all-original, more of a resto-mod. We've never even heard the engine run. I figure if we can get the motor to fire up then that will give us some enthusiasm to keep rolling with everything else.
After pulling the flywheel and messing around with the points, tracing wires, and addressing the coil grounding, we finally got spark the other day. The coil looks like a japanese motorcycle item, not the correct kohler one. The piston and cylinder walls look pretty good and compression feels right to me although I haven't tested it yet.
I have a bunch of new parts coming- new coil, starter solenoid, regulator/rectifier. The wiring harness was a complete train wreck. I counted 4 splices between the magneto and the ignition coil! We'll have to make a whole new harness, luckily it's pretty simple. I also have a rebuild kit for the Tillotson HR125 coming from EC Carbs in TN, they were very helpful. I should probably replace the crank seals, just because.

I think you are correct that the Ruppsters came with a JLO-230, and this Kohler is probably not the original engine. I removed the engine mount from the crankcase last night to clean it and I could tell someone drilled new holes in it for the Kohler. This engine was on it when we bought it so we're keeping it. It does have a Rupp clutch though. Once it's running I'm hoping to rework an expansion chamber from a 250cc MX bike to replace the agricultural looking exhaust system it has now.
 
#8
Sounds like you guys are all over it. Like to see some pics if you get around to it. I've been working on mine off and on for a few years. I squeeze it in between all the other crap I'm working on. Can I ask where you found your coil & rectifier?
 
#9
Well, it sat here for a few years until we finally found some time to work on it. I dont have any photos worth showing yet. Right now it looks like a Rupp yard sale more than anything!
The regulator/rectifier is a generic 4 wire unit I got on ebay. I'll wait and see if it's any good. Should be simple to hook up, I hope. Hook 2 yellow wires coming from stator to AC inputs, the other 2 are 12v DC coming out of rectifier.

The coil is also from ebay but says it's the correct part for the Kohler engine. Looks aftermarket but if it fits and works I'm ok with that.
Again, I'm not ready to recommend it since it's not even here yet.
http://rover.ebay.com/rover/1/711-5...0001&campid=5335845805&icep_item=202815468808

I have to make a new mounting bracket anyway so I could use anything that's compatible electric wise.
 
#10
Ok I have some updates. After much messing around with points and wiring we have spark. I got the Tillotson HR rebuild parts from EC Carbs. Totally stripped carb and cleaned in ultrasonic. Put it all back together and fired it up! Jeez its loud. The exhaust is a Donaldson power-tuned. I researched it a little but and may decide to leave it on. That exhaust is fairly well regarded by the vintage sled guys. I'll try to adapt a 2 stroke silencer somehow because it's really loud.
The coil that I bought bolted right up to 2 threaded holes in the back side of 5he flywheel shroud, so I guess its correct. I'm still waiting for new points and condenser. They're cheap enough that I might as well get new ones. I'm having a bit of trouble getting the timing set per the manual so new points may help.

Next up is the clutch. I hope someone here can shed some light on it.
 
#12
So here is my question with the clutch. It's a Rupp clutch, 30mm taper mount. The fixed stationary sheave has a collar next to it that is floating loose on the shaft. Its aluminum like the sheave, looks like it may or may not have broken off the sheave.
Also there is a split bushing like a teflon and bronze DU bushing with a steel outer shell. This fits inside the the aluminum collar loosely. I dont understand the purpose of this part. The spring cap sits against a shoulder on the shaft when it's all assembled, not against the split bushing.

If anyone thinks they may have some insight, let me know and I'll post photos.

Thanks
 
#13
No updates here lately but we have been making slow progress. Here is the clutch that I desribed before. I think I figured it out. The floating aluminum collar with DU bushing is there to let the belt slip and freewheel at idle. These parts are trashed so I'll need to make a new collar and source the correct size DU. Also need to polish that shaft so it can spin more freely. We fired it up with clutch in place and it definitely drive the rear axle as it should. Hard to get it to stop though even at idle. Also nee to work on cleaning up the driven clutch so hopefully it will backshift when needed.
I made a mandrel to match the crank taper so I could spin the fixed sheave in the lathe. Took a light skim cut on the faces just to clean them up, that seemed to help a lot.
https://photos.app.goo.gl/EfxcZa7d3DVnxuCG7
 

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#14
As mentioned before, wiring on this buggy was a disaster. There were poorly crimped splices everywhere, and the solenoid and regulator/rectifier were just randomly hanging loosely from the rear body support bar. We made a new battery box and hold-downs. The regulator/rectifier is mounted to the left side. The solenoid and a small fuse panel are mounted to the right side. I also added a 5/16 ground stud to the front of the battery tray. The neg cable from the battery connects here, as well as ground cable to the engine.

Pics of the OLD battery tray. My wife said "you're not gonna leave those welds are you?" Of course she was right, they had to go.
 

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#16
to secure the wiring harness to the frame, I used a detail that I saw on a racecar somewhere. Bend a washer to approximately 60 degrees, then weld to frame in 2 spots. The "V" cradles the wires and the gap between washer and frame is perfect for a zip tie. Clean and very secure. 20200828_063848.jpg 20200828_063848.jpg 20200828_063841.jpg
 
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#17
I just bought another ruppster, am i process of rebuilding. I dont get on here much but its snowing here today so killing time . I have had a lot of rupp over the years ,dont claim to be an extpert ,but the collar in your clutch is for the belt to ride on so at idle no tenison on your belt so dont squall.
 
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