OC 46 3G runs bad

[yaldwyn]

Hello,

I have a OC 46 3 cylinder gasoline crawler which has not been running well for a long time. In fact, ever since I got it, it never ran properly but to many other projects kept me from attending to this machine.

When I first got it it ran, but it never sounded happy. It did not run smooth and it always backfire a little.  Lately, it only runs for about 10 to 15 minutes. It seems that when the water temperature reaches about 200 degree F, the engine stops.

I got it about 4 years ago and ever since, it needs choking for long time before the engine stays on without it. Depending on the outside temperature, this can be anywhere from one to four minutes.

Last summer, I changed the spark plugs, spark plug cables and rotor. This did not make a difference.

Any suggestions?
Thank you very much,
Johannes

[AdamPerry]

I had the same problem with my machine. It would run for about 20 minutes and then break up. After an hour of cooling down, it would run for another 20 minutes. It turned out to need the magneto rebuilt. This is a problem that pops up on these pages often. Check out Phil's posts a page back for example. Good luck.

[John Schwiebert]

The 3 cylinder does not have a mag. First of all have you checked compression? Do you have a vacuum gauge? What color is your spark. If you unhook the gas line at the carburetor and stick it in a bucket how freely does the gas flow for a minimum of say 10 minutes? Have you had the sediment bowl out of the tank? Start with the basics. I think they had a fuel pump, have you checked the output?

[yaldwyn]

Thanks, indeed no mag, some other guys blamed the coil. However, like John, I suspect the fuel delivery. I will start with the basics.

[oliverchris]

There's a sediment bowl in the tank???...thanks John! I was worried I had no filtration on the fuel line!
I have same running problem and it 'feels' like fuel delivery or maybe the coil. Runs nice and strong and then starts to stutter and burp!
Mine also has a different fuel pump to the manual...but then my manual is an older edition than my OC4.

[oliverchris]

I definitely don't see any filtration or sediment bowl etc.
Where is it meant to be on an OC4 series B (3 cyl gas)?
There is sure to be some bits of rust and such in the tank and I don't want that getting to the carb.
Many thanks, Chris