Gas In the OIL

[William V.]

How many of you have seen or experienced this? Is it common?

A C2 or C3 is parked on a hill with a full tank and nose pointing down. The needel and seat leek allowing gas to drip through the carburetor & manifold and fill cylinders and the oil pan with raw gas. (several gallons) I saw this twice with Holleys but I suppose it could happen with other type of carbs

[Clem Z.]

this was a big problem

with the 3X2 427 corvettes.this is why a lot of 427 corvettes do not have the orignal engines. the problem is caused by the fact that the end carbs have the nitrophyl floats and have a shorter level arm than the brass floats and these do not have the mechanical advantage the brass floats to close the needle and seat. if you add weight to the nitrophyl to make it weight the same a brass float will help some with the problem. vented to the outside gas tank cap will help relieve the pressure in the fuel tank. the heat from the mufflers help bulid pressure in the tank. if you have a "take apart" fuel pump you can drill a .015 hold between the vacuum and pressure side will allow the pressure between the pump and the carb to be relieved.

[Terry M.]

[Clem Z.]

help yourself and do what you need

as i have no pictures and even my memory is fuzzy since i have not done any of this type of work since the 70s

[James F.]

Re: Sounds like a tech tip here- Terry

Terry,
I recall vaguely there was published a year or two back, in "Vette Views" Alan Kaplan's Factory Facts a Service Bulletin suggesting drilling a small hole in the fuel pump. I think this may have had something to do with high pressure in certain C-2's. I have no way to crossrefence Alan's prior submissions to "Vette Views" and what I think I may recall. Regards,

[Bud Landacre]

Re: fuel in oil

Several years ago I had a problem with fuel in the oil pan. Turned out to be a ruptured diaphram in the fuel pump allowing fuel into the oil pan via the fuel pump push rod hole.

Bud Landacre
Red 62

[Clem Z.]

the gas ran into the pan thru the oil return hole

that runs from the fuel pump boss back to the pan. this is how the oil that gets passed the pushrod gets back to the pan.