Gas in the Oil pan
Asked by Uriahjw Sep 10, 2014 at 11:23 PM about the Chevrolet Camaro
Question type: Maintenance & Repair
I have a 1969 C-10 half ton Chevrolet truck with a 1970 472 Caddilac engine and turbo 400 transmission. I have an eldelbrock 750 carb with An edlebrock manifold. the fuel pump is an electric fuel pump. I have recently seen fuel pooling on the manifold coming from the main shaft shown in the picture. My truck has the original gas tank which mean it doesn't have a breather gas cap. Once I opened the gas cap and the pressure was off I let it set over night and the next morning I didn't see any fuel on the manifold, but what I did see is fuel leaking from the pullys in the front of the engine. I looks like it is coming from the crank shaft. One quick check of the oil and I found gas on the dipstick. I wonder now if I have something major going on like a cracked manifold or blown seals? can anyone let me know what to check first?
6 Answers
I think the float,may be stuck in the carburator,or you have a intake gasket leak.
It also sounds that your electric fuel pump may be pumping gas after you shut off the engine. Is it wired to run when the ignition key is turned on even if the motor is not running? Then you are pumping gas into the carburetor after you shut it off, and it is going down into the intake manifold, into open valves to the cylinders, then into the motor oil pan. My 1969 Corvette has a gas return line from the manual gas pump to the gas tank to send the extra gas not needed for the engine. Does your truck have such lines? If so, try to get it hooked up to relieve the built up pressure form the electric fuel pump. The gas on the pulleys also could be the gas overflowing from the carburetor onto the intake and then down the front of the engine to the pulleys. Major fire hazard. Make sure your house and car insurance is paid up and adequate. When I had my engine rebuilt, the people that put the engine back in my Corvette tried to block off the return line and I had gas shooting onto the exhaust manifold. I was lucky it did not become a spot on the 6 o'clock news.
Hey guys thanks for your replies.First TST I am not sure if the float is sticking or not I am having a guy come out to evaluate the situation, but for me that is what I am thinking. Also the Vacuum advance I just found out is on the ported side of the carb and in the maual it needs to be on the other side.so that I am thinking is not helping the problem. Second, Califcarson the pump starts once the key is at the " on" position, just before you start the truck. but once you turn the truck off it the pump turns off. my tank does not have a return for the fuel. The guy I have coming didn't seem too worried that there was gas in the oil pan. I am hoping that there is no real damage to the engine and that we don't have to do any major repairs. If I find that the carb is the problem I may have to go to Edelbrock's E-Street EFI Fuel Injection System, this would take out much of the headache problems that come with carburators. Thanks for your advice I will make sure I ask the guy coming over on monday.
If you have the dough, that's the way to go. Great set up. I had gas leaking from my Edelbrock carburetors, and had to rebuild them. I had gas coming out from around the choke rod and the flat gaskets the top of the carburetor bolted together. Good luck, have fun and enjoy. Trying to "guess" the issue on line is really hard, not looking first hand, we can only guess at what may be the solution, and at times the information is really vague. There are so many after market products out there, it's hard to keep up with all them, and sometimes they are modified and the owners don't even realize it.
Hey guys just wanted to let you know that we think we have the problem solved, It seems that the gas cap that we have was not letting the gas tank breathe properly. more to the point expell the pressure bult up. After a qiuck cut of the spring it the tank will now be able to breathe more easily and our fuel leak problem should be solved. thanks to everyone for your help. Uriah