View Full Version : Gas in oil pan

12-05-2013, 12:43 AM
Hey guys,

So I drained the oil in my '64 tonight to prepare to pull the engine, and as soon as I pulled the drain plug, I was hit with the smell of gas. I know there's several reasons this could be the case, but there's one thing that's sticking out as the greatest possibility.

The block itself is caked with oil, and according to the previous owner, this engine is freshly rebuilt (no documentation of this whatsoever, I'm taking him on his word at this point, but you can believe I'll be pulling it apart to make sure). Whether it was or not is not my concern at the moment, it's that caked oil. I'm thinking that when/if the intake manifold was replaced on the block after this supposed rebuild, the person who reinstalled it did not allow the intake to settle before torquing the bolts, thus creating an improper seal between the intake and the block.

Does this sound at all correct? I have not pulled the plugs to check for fouling yet, so I can't rule out the carb, and when it runs, there's no evidence of any misfire.

Any help or ideas of what to look at would be appreciated. Thanks in advance gents.

12-05-2013, 01:07 AM
Sometimes the intake manifold won't seal correctly at the front and rear. Some people use the gaskets that come in the kit and it can leak after time; some people use just sealant without the gaskets. I use both the gaskets and sealant and haven't had any problem with oil leaks.

As far as the gas smell I would suspect the fuel pump. A bad diaphragm will cause gas to leak into the oil pan.


12-05-2013, 01:16 AM
Thanks for the quick reply John. That was also on the list of likely culprits. I'll have a look at it and let you know what I find.

12-05-2013, 02:19 AM
Caked oil is usually caused by blowby. Blowby is usually removed by detergent oil if the oil is allowed to get hot enough.

It could be that this engine never warmed up each time it was started.

When you tear it down, the truth will show itself. Post some pics. - Dave

12-05-2013, 05:23 AM
The few times this happened to me on various cars pull and replace fuel pump dry rotted or pin hole in diaphragm wu
Will pump fuel right into pan. Jeff

12-05-2013, 08:19 AM
Thanks for the replies guys. I hope to have the engine pulled in a couple weeks, but with the holidays fast approaching, it may take a backseat. I've got a 12 hour drive to SE Michigan coming up. I'll let you guys know about the fuel pump though, and the status of the supposed rebuild as soon as possible.