tripower problem

[Thomas C.]

I had my 69 tripower carbs rebuilt over the winter because the car would not idle correctly. When I installed the carbs and started the car I ran it for several minutes and it smoked blue /black exhaust. I then found that the float level was very high as gas was pouring out of the sight hole. I adjusted that. Then I started the car again and still smoke from the exhaust. I then noticed that the crankcase was over filled and smelled of gas. Changed the oil. I also noticed that gas was coming out of the pcv port when I removed the hose. This is where I am at now. I have not started the car since. I suspect gas had started to enter the crankcase before the carbs were rebuilt because the car smoked almost immediately on start up. Could the incorrect float level have allowed such a rich state that fuel entered the crankcase? Or some other cause? What would cause fuel to drip out the PCV port after float level adjustment? Any help would be appreciated. Tom

[Clem Z.]

Re: tripower problem

this is what "blew up" a lot of tri power engines back in the 60s and why a lot do not have their orignal engines. if your gas cap is not vented to the outside i would replace it with one that is so the pressure does not built up in the gas tank and over run the carbs. we just drilled a 1/8" hole in the caps back then. the heat from the mufflers heat up the fuel in the tank and it builds up pressure and forces the gasoline past the needle and seats and since the tank is as high as the carbs it just keeps running. i have seen them with 2/3 gallons of gas in the oil pan. you need to pressure check the carbs needle and seats to make sure there is no leak thru at pressure by pressurizing the carbs at 8/9 pounds with air with the carb upside down. i have made a special set up to do that on all carbs i rebuild.

[Clem Z.]

PS you could also have a bad fuel pump diaphram *NM*

[Terry F.]

Re: tripower problem

I agree, I would check the fuel pump diaphragm. Regards, Terry

[Dan M.]

Re: tripower problem

I can suck air through my new vented cap for my 1969 but can not blow through it;is this correct? ie should this cap act as a one way check valve and only allow air into the tank but not out of the tank.

Dan

NCRS 35068

[Clem Z.]

Re: tripower problem

i am not sure what year they went to the non vented to the atmosphere cap but yours sounds like it. i would try and get a vented gas cap.

[Thomas C.]

Re: tripower problem

Thanks for the responses guys , I'll look into the fuel pump. I assume that if the diaphragm is bad then the pump builds too much pressure causing flooding?

[Clem Z.]

Re: tripower problem

no the diaphragm is leaking thru allowing fuel into the oilpan thru the oil return hole in the block.

[Jim T.]

Re: tripower problem

Clem is it also possible that someone could of installed a high performance fuel pump that is putting out more pressure than the needle and seats can handle?

[Clem Z.]

Re: tripower problem

you need to temporarily install a "inline fuel pressure gauge" to check the pressure. it should be in the 6/7# range