: Your thoughts on this oil leak?

05-07-13, 10:28 PM
Did an oil change on mom's 84 4100 today. Used my new tall funnel, so it holds about two liters. Poured in half a jug, the funnel drains slowly, the opening is only the size of a dime. As the oil goes into the valve cover, fresh oil starts to dribble down the back of the block. Quickly. Makes a decent puddle. I pour the rest of the jug slowly, no more oil down the back. I am 100% certain the funnel was IN the hole in the valve cover. My theory is this: the top of the head had a lot of oil in it, the oil couldn't drain in the drainback holes quick enough, and the oil level came up to the level of the old dried out valve cover gasket. This caused the dribbling leak that stopped when the oil level on the top of the head. It doesn't dribble when running (I ran it for about 5 min after the change). I'll do valve cover gaskets tomorrow, but I'm always open to ideas.

05-07-13, 10:53 PM
Sounds right to me. Maybe put a little engine cleaner in it.

05-07-13, 11:50 PM
Does your Mom's 4100 have those little rubber V gromets at the far ends of the valve cover gaskets?

05-08-13, 12:07 AM
I have no idea, what are they? Pic?


I have no idea, what are they? Pic?

05-08-13, 01:48 AM
I have no idea, what are they?

This is from a FWD but you get the point.107714

05-08-13, 08:47 AM
interesting...I'd say the valve cover gasket would be the first place to check also. Or maybe the oil drainback holes could be getting gunked up too?

05-08-13, 10:03 AM
Hmm. The leak would have come right from that area of the V, I would say. I have never heard of those V gasket parts. Will they come with a valve cover set? I guess I'll find out. (Checked Rockauto, the V parts are included). I'll also be able to see them when I get the covers off. WTH are the for? More 4100 craziness.

I'll clean out the drainback holes, too, but they're probably good. I change the oil on this thing once a year, and it's as clean coming out as going in. The cleanest oil of any car I work on. It was a GM replacement engine that went in at 55k, and the car now has 147k on it.

05-08-13, 01:47 PM
The v seals the gap created by the intake, head, and valve cover. It's not just a single flat head surface for the valve cover to seal on - the cover seals against both the intake and the head. Remember, on these, the intake manifold extends under the valve cover. The pushrods even extend through it. It's not unlike GM's popular 60 degree V6...

05-08-13, 03:09 PM
Makes sense. Any install advice? Glue the Vs in, glue the gasket to the cover, torque down?

The Ape Man
05-08-13, 06:05 PM
I'd clean the whole shebang with a good fast drying solvent then goober some RTV right where it leaks. Done. Saves peeling it open.