787 wont stay running

[slayton28]

I have a 1997 787 that when you choke it and start it up it will die out about 30 seconds to a minute after it has start could this be dirty carbs?
The next question is should there be any play in the rotory valve?

 

[LouDoo]

It could be a lot of things. Do you still have the grey fuel lines? Could be carbs. fuel filter(s), fuel selector valve, bad gas, water in the gas. What's your compression? No there shouldn't be any play in the rotary valve. Is it loose?

Lou

 

[slayton28]

Yes I took the carbs off to clean them and noticed that the oil line coming from unber the exhaust didn't have any oil in it so I checked the valve and when you turn the crank you can push the valve about an 1/8'' eather way and didn't think that was good.

 

[LouDoo]

Is the oil line you're talking about the one coming from under the engine or is it one of the small injector lines?

Lou

 

[slayton28]

The one from under the engine the bigger one

 

[LouDoo]

That's the return line it will have air in it.

Lou

 

[slayton28]

So that is OK how can I check and make sure the lower end is getting oil

 

[LouDoo]

If you have the carbs. off you can turn the engine over and see the oil pump out of the small tubes in the intake manifold at the base of each carb. If you haven't already done so you should replace the small injector lines with 3/32" tygon fuel line, then you can actually see the oil in the lines.

Lou

 

[slayton28]

I don't have those lines when I bought the boat the guy bipassed the oil pump and now I mix the gas but the oil tank is still there and the big lines are still hooked up to the bottom sides of the motor.

 

[LouDoo]

O.K., the only thing that the oil in the tank does is lubricate the rotary valve gear. Lubrication to the engine is from the oil mixed with the gas.

Lou

 

[slayton28]

Thanks for you help I'm going to change the fuel lines and filter and put the carbs back on in the morning and we'll see what happens

 

[Jfrymania]

Did you get it fixed, Slayton 28? I'm having the same issue with my speedster. Thx