While changing out my valve cover gaskets I noticed a faint smell of fuel. Under the cover there was a foamy substance kinda of caramel color and a grayish film around the return ports on the heads. The engine is the original 350 with less than 80k on it. Wondering if it is valve seals leaking or over run from the carb. Ideas?

 

I would usually associate a gray color to moisture where oil is present.

 

Both sound normal, gray from the older oils and caramel from condensation if it has been sitting and had short start-ups. How extensive was the caramel? Can you post a picture of it? A couple of short interval oil changes and full temperature road trips will usually clean it nicely.

Although not part of your original post, have you considered replacing the timing chain and gears? If it is original the cam gear is 45 year old plastic.

 

Sorry but I cleaned it before I thought to snap a pic. It has been sitting a bit while the resto project has been going on. That would make sense that it hasn't had a lot of time to circulate the oil. Thought I would drop the oil. Pan and clean the pickup screen while I was at it. Thanks for the timing chain/gear suggestion too. It was done about 4 years ago while the water pump was being replaced. It just hasn't had a lot of road time lately. Just was concerned I needed to go ahead and pull the heads for a quick valve job with all that stuff in there. It was kinda a cream colored, not thick if that helps.

 

As far as the amount of foam, it was limited to a band right down the center of the cover. Possibly, a couple of oil changes done in 500 to 1000 mile intervals?? What would y'all think about adding a quart of marvelous mystery oil to help flush it on one and run it 500 miles then dump it and add 5 fresh and a new filter?

 

Watch your coolant level for a while see if it drops down a little.

 

Check your PCV valve. See if your vacuum hose is not cracked, kinked or loose connection. Take the valve off the hose and shake it to hear a rattle. If it doesn't rattle, you can clean it with carburetor cleaner by spraying the inside and plug it with your finger and shake it.

 

Done all that. Checked the water level and marked it, checked hoses, cleaned the PCV, it sounds a lot better. Will have it all put back together next week when I get back off the road. Thanks for the suggestions.

 

Would just do two or so oil changes at 500 miles using quality oil and filters. A key to success is getting the engine to full temperature for extended periods to burn off any moisture and clean things. Change the oil hot so that contaminants are held in suspension and come out with the oil. Of course, be careful not to get burned!!! Hot oil on skin = not good.

Be cautious with aggressive cleaners or flushes as they could break too much loose at one time clogging a passage. As far as dropping the pan, if the old gear was good then the pick-up should be ok, if the gear was missing teeth/nylon then dropping the pan is a good idea.

It does not sound like pulling the heads has been determined to be necessary yet, but if the foam does not go away then look further. Coolant in oil, if that is the case will destroy bearings quickly. If the compression is good I would wait to pull the heads and avoid ending up with thicker head gaskets and less compression.

And for a might as well, the valve seals are probably tired but can easily be replaced without pulling the heads. Just my two cents...good luck!

 

Could it just be the steam from shutting off and then it cooling on a cold night?

 

Billmerback, I would be ok with that but it does smell like fuel. Sugar Bear I haven't given it a lot of thought to use heavy duty cleaners. Hearn nothing but horror stories about them. But MMO isn't a heavy detergent agent. It can go in the oil or gas. Leaning towards a carb rebuild to kick start it. Have an idea it may be force feeding the engine too.

 

Fuel in the oil can be from short trips and/or a carburetor problem. Cleaning the carburetor on an engine that has been out of service for a long time is a very good idea. What carburetor does it have? Would you clean/rebuild it yourself? If you think it is original, rebuild yours don't replace it.

An after thought about the MAW valve seals...as they deteriorate they may end up in the pan. If you decide to pull the pan consider doing the valve seals first.

Sure is a lot easier to suggest these repairs than to perform them

 

Good info. And I believe it to be the original Qjet. It's a L74 350

 

Everything you are describing sounds like a lack of going for a long enough drives. A little fuel smell is probably from the choke staying on a little longer than it should, the foam in the oil is most likely just condensation and both will go away if you drive the car long enough to get the oil good and hot which causes the fuel and water to evaporate.
As far as gray in the oil I'd beat someone alone the line dumped a can of STP or something like it in the oil, that crap settles out here and there in the engine and once again of you don't get the oil hot enough it won't flush it out and keep it suspended in the oil.

 

Sounds good. I got to pit in the upholstery shop to get the top put on then I will drive the **** out of it and change the oil out a couple of times