What if the Oil Bypass valve is stuck?

hecmanortiz · 11-21-2010, 07:34 PM

So I've got this '85 12A that was sitting for a long time. Replaced the tank and fuel pump, rebuilt the carb got it started and can't get it to idle. Basically it would start up strong and then start stumbling but never idled so I had to crank up the idle. I always noted that the oil was too clean. After a while it has started smoking a little bit when I start it up but it clears up. That stumble is still present. Today I went to change the oil(after the initial change in May since it has been pretty much running in my driveway) and the oil filter was pressurized. After I broke the seal on the oil filter quite a bit of oil came out and the filter base was full of oil. It seems like the oil(or most) hasn't been going through the behive cooler. My understanding is that the oil goes from there through the bypass valve which diverts the oil somehow to the e-shaft.

So I'm thinking that I'll have to remove the oil cooler(replace the O-rings while at it and remove the valve to service it. Am I on the right track here? Anything else I should be wary of? I'm obviously worried about permanent damage to the internals from lack of lubrication. How about the pressure regulator valve?

Thanks for listening and for any input.

Hector

11-21-2010, 07:34 PM	#1
hecmanortiz Rotary Fan in Training Join Date: Aug 2009 Location: Hamilton, Ohio Posts: 40 Rep Power: 0	What if the Oil Bypass valve is stuck? So I've got this '85 12A that was sitting for a long time. Replaced the tank and fuel pump, rebuilt the carb got it started and can't get it to idle. Basically it would start up strong and then start stumbling but never idled so I had to crank up the idle. I always noted that the oil was too clean. After a while it has started smoking a little bit when I start it up but it clears up. That stumble is still present. Today I went to change the oil(after the initial change in May since it has been pretty much running in my driveway) and the oil filter was pressurized. After I broke the seal on the oil filter quite a bit of oil came out and the filter base was full of oil. It seems like the oil(or most) hasn't been going through the behive cooler. My understanding is that the oil goes from there through the bypass valve which diverts the oil somehow to the e-shaft. So I'm thinking that I'll have to remove the oil cooler(replace the O-rings while at it and remove the valve to service it. Am I on the right track here? Anything else I should be wary of? I'm obviously worried about permanent damage to the internals from lack of lubrication. How about the pressure regulator valve? Thanks for listening and for any input. Hector