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Discussion Starter · #1 ·
Working on installing an older Rotax 299cc into an EZGO. Everything has gone well thus far, but I think I'm having exhaust related problems. I installed the pipe that came w/ the motor (but it was in very bad shape) and she smoked a ton and had 0 power. Then, I tried a straight pipe and it ran better, but was un-godly loud and would not rev as much as it should have. Now I'm at a loss and any suggestions would be great!

 

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Does it spin up better without a load on it? (Unhook the belt). This will test if the clutch is working OK. Also remember, snowmobile engines are jetted very rich for use in cold weather. You might have to lean it out slightly to get it to rev up.
 

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what posessed you to do this??? thats awesome! smallengineguy's ides sound good.

i have a 500 cc rotax layin aorund here... now i gotta find a golf cart! or some other frame...
 

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Discussion Starter · #4 ·
Thanks.

So you don't think its the exhaust?

Getting the belt off is a bit of a pita (but its in neutral so there really is no load now)... I have to loosen the engine mounts.
You wouldn't know how to lean it out, would ya?

Why do this? I'm a complete freak. I spend all my $$ racing and wanted to design the ultimate pit cart. The body work is being painted (will match the car, of course) and I am building a deck on the back that will have a built in tool box and a rack for 4 tires.
 

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First off, if I ever feel the need to own a golf cart in my older years... I'll be looking you up.

Your exhaust issue could be part of the problem, but it seems to me that if it gets very little power with both the pipe on and off, there may be another underlying issue. But to start things off, since you say the pipe is in such bad shape anyway... buying a new / used pipe in better shape is probably the best start.

Oh and... be sure to post some pictures of that golf cart when its all done.
 

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One of the screws on the side of the carb will lean it out. Give it some throttle and turn the screw inward slightly and see if the revs come up. Don't go in too much because the engine will lean out and burn up. You will be able to tell when it's running right.
 

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Discussion Starter · #8 ·
I found a new carb on Ebay tonight for $25... figured it would be cheaper than rebuilding this one (if it needed it). I'm going to a m/c scrapyard tomorrow to pick up a 2 stroke exhaust pipe...
 

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Discussion Starter · #10 ·
Thanks for the suggestions.

I built a combustion chamber pipe and installed the new carb... what a difference. It revs nicely and the clutch does engage- you can watch the primary contract and the secondary expand. The deal w/ the belt is that it is a bit more narrow than the EzGo belt- its not too tight, it just does not fit quite right.

Now, I need to tune the carb. It won't stay running at idle, in fact, it really has to be "goosed" (high rpms) to keep her going. There are two adjustment screws on the carb (a Tillotson HR7A) one marked H and the other L. Any suggestions?

BTW-

The Robbins is ok for a motor, but because it red lines under 4k, you just don't get too much faster than 20mph. Also, I sold the Robbins for more than I have in this whole project. Besides, this is fun! I might pull this motor and install a 500cc this winter if everything works out ok.
 

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You need to adjust the (L)ow speed air screw first. Static adjustment is 1 1/4 turns from lightly seated. Go a quarter turn each way to see what difference it makes. If your power band is good, the (H)igh speed seems OK. It sometimes helps to go out another quarter out on that one also. Let us know what happens.
 

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Looks like your project is really rolling along! A few days and you might just have it done... minus all the paint, gun racks, mud tires, and other accessories. :)

Looks great.
 

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Exhaust problem.

A lot of the older engines require back pressure to build power. I put a rotax 440 in my g16 YAMAHA. I used a exhaust pipe from a john deere spit fire. It did require some modifications. If you would like to see pictures let me know.
Thanks
Paul
 

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this is awesome! this is actually whats in the way of me finishing my race truck(mitsubishi with a 12:1 355sbc), and isnt it nice to have 4 wheels and a seat at the track? around here pits are soooo long on hot days walkings retarded..i have a 95 yamaha g9 i think it is and i just finished building an 8" lift kit for it, im putting in an OLD omc engine(it was free), today or tomorrow im bolting motor in not much room for exhaust eh? although after rerouting throttle cables directly to carb off governor and reworking exhaust a bit the stocker was pretty surprising..good luck with build, i love seein ppl doin this stuff hah
 

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Once you get the carb issues worked out, the next would be the clutches! With out the exact c/c distance, you may have to work the motor back and forth to get it working right! You want the belt to rest as high in the secondary as possible(even out of it a bit) then move the engine away untill the belt starts to squeel, then back it up!
 

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have had it out only like 2 times now sleddin season is comein and i got a few sleds to work on for people includeing my own, so now its for sale $700, about 90% done. 608-963-1152 or email [email protected] if you want a description and pics,
 
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