I don't understand it. The seal between the front of the oil pan and the timing cover has a slight drip. I just don't get it, oil comes down from the cam to lube the timing gears, but the timing cover has an overhang, for some reason oil is still finding a way out between that seal.

I used the thick from seal and an oil pan that required a thick front seal.

Put a nice bead of RTV silicone and it still has a slight drip. I just don't understand why the oil wants to come out that way when there shouldnt' be any force.

 

You sure it's that seal?

Got a SHORT bolt in the upper hole on the right side of the front of the block, where the smog pump bracket used to be?

 

Yep, 100% sure, there is a bolt sealing the smog pump hole. I laid under my car while it ran, and saw the drip. It's only at the very bottom of the seal. The front of the oil pan is U-shaped, well it's only at the very bottom of the U where a single drip will fall every 15-20 seconds. It's driving me nuts, the oil pan is torqued to spec. I used solvent to get any oil residue off and then I just RTVed the **** out of the entire front and oil is still finding a way to drip every so slightly. None of the rails leak on the side. It's just the front. I'll take a picture tomorrow when I go under again.

 

Well, then I guess it has a leak there.

Make sure it's not the front seal, either around the crank, or where it fits in the timing cover. Wherever the leak is, lacquer thinner the hell out of it with a toothbrush, and try to force a little silicone in the gap by smearing it in with your finger.

 

Two things to think about trying:

1.) Instead of regular silicone RTV, "The Right Stuff" is worth trying. As RB said, clean things up and then smear it into the junction. Right Stuff is stickier, tougher, and generally better than silicone.

2.) You could slightly deform the oil pan to increase the pressure on the pan gasket by tapping it along the exterior ridge/lip. Use a 2x4 or other wooden object against the pan, and a hammer to tap the wood.

If it was a new oil pan, and you didn't scuff up the sealing surfaces to remove the paint, chrome, or other coating, that's a likely cause.

 

I was supposed to scuff up the chrome?

It's not the front seal, I laid under the car while it was running and the oil was visibily leaking where the gasket met the bottom of the oil pan where it Ued. It's a 1 piece gasket (I well aware many people here swear against them so I'd rather not hear about it as it's already in there).

It just boggles my mind why the oil is leaking out of the front like that. I mean, there is no pressure there, nothing forcing the oil out. It leaks when just idling, it's not like the oil is splashing around when I drive and leaking.

 

Oh man... I wish you'd have said earlier you were using chromed tin; but I guess everybody has to learn the hard way, at least once, though.

You shouldn't use that stuff if you can help it; but if you can't avoid it for whatever reason (for instance, I'm driving one around on another car right now, the timing chain wore a hole in my stock one and the dealer was out and all I could find in town that day was chrome) the most important thing you can do is to SAND THE CHROME OFF OF THE SEALING SURFACES. Sealer won't stick to that stuff; not a chance.

It pretty much needs to some back off, and be sanded, and put back on.

Hopefully that's the only leak you've got.

 

Well at least I know why it's leaking then. It was just driving me nuts because I know when I put the engine together this time it was done as perfectly as possible.

Thanks

 

Many people here also build engines that eat oil, spin bearings, and reflect a host of other assembly defects.

1-piece pan gaskets go together easier, and if they don't leak initially they'll usually outlast the 4-piece ones.

The timing cover gets sprayed with oil thrown off the timing set, so it's definitely exposed to oil under force that will find any possible exit.

 

Dude when I had a leak from that hole I was $h!tt!n a brick.......lost a quart anout every 2 stops......oil would pour out but only when I was moving.......so when I got underneath I could never really pinpoint what "seal" was leaking........never thought it would be a bolt hole.......by the way whats the best way to seal that bolt.......I think mine is stripped.....I got one to thread in there but not far......stopped that leak........well I stopped a hole in my engine anyways...

 

I had the same type of leak on my 406 shortly after the initial start up.

I am also using the thick front seal. Try taking a feeler guage and trying to slip it between the gasket and the oil pan right under the timing cover. Try to use .003-.004" feeler.

If you can slip it in, try retightening all of the oil pan bolts. I tightened mine starting at the front of the pan and worked my way to the back side to side. Don't wory about the recommended torque specs. Just tighten it up snug without wrenching the **** out of it. You will have to do this a couple of times.

Good luck!

www.geocities.com/dzperf

 

I had problems with my one piece oil pan gaskets getting weepy on my engines just like yours. I actually went away from them for a while. Now I'm back.

What I do to make them seal up is to use OIL on the OUTSIDE edge of the seal around the half-moons front and back (this is very different, and not in replacement of, the 4 little blobs of RTV I put against the BLOCK in the corners. This is on the OUTSIDE edge of the gasket that the pan touches.)

WHY?? Becuase the one piece seal is MUCH thicker than the usual multi-piece gaskets. This is meaningless where it's flat (along the rails) but in the half-moons this means the pan has to squeeze the seal INWARD towards the crank as the pan pushes down that last 1/4" or so. This means the pan MUST be able to slide easily along the outside of the gasket to allow it to compress inward as well as let the pan seat down on the rails. If it can't (like if all the parts are dead-dry on assembly) it'll sometimes grab on the sides of the half-moons and try to pull them down, distorting the gasket as it pulls. TA DA!!! Instant leaker.

I use NO RTV along the outside of the gasket that the pan touches whatsoever, just in the 4 corners in the usual spots against the block. Loading RTV along the half-moons never did anything to help it seal up better in my experience.

One other thing- like I mentioned above, the one piece oil pan gaskets are MUCH thicker than the stock pieces. So thick that the "thin" style one piece gasket might just be thick enough to almost seal up even in a "thick" style gasket application. You SURE you have the right gasket? If I recall correctly, it's the PAN that determines if you need a thin or thick gasket, not the timing chain cover. You're using a non-stock pan so.....

 

The oil pan I bought from summit was stock replacement.

http://store.summitracing.com/partde...501&Ntt=chrome oil pan chevy&Ntk=KeywordSearch&N=110&PartSearchFlag=

It says to use thick front seal gasket set.

So I bought the blue fel pro 1 piece gasket w/ think front seal. I had the engine upside down on the stand when I put the oil pan on. RTV in all 4 corners of both sides of the gasket. The gasket is dripping ONLY at the very bottom of the front and back where it U's. I was very careful when I put the oil pan on that the gasket was sitting correctly on both the rear main cap and the timing cover slot.

I'm not taking the engine out again, so I'm just going to keep RTVing the thing til it stops. It's only a very slight drip at this point, so I'm just gonna keep at it.

EDIT: The fel pro 1 piece has white plastic washers built into the gasket, you can't only tighten the bolts so far before the washers stop you. I torqued all the oil pan bolts down to spec, another 1/2 turn the gasket washers won't allow the bolts to go any tighter. The bolts are all as tight as I can get them.

Just amazes me how I can take a cup of wawa coffee and hold it upside down and the goddamn snap on lid holds all 20oz of coffee in leak free, yet the timing chain is flinging a little bit of oil on the seal area and it wont' stop dripping.

 

Grab a cheese-whiz can of The Good Stuff and use that, not RTV. That stuff will seal anything and keep it that way.

 

Damn chrome oil pans suck anyway. I've rarely ever seen one that was strait. When you take yours off, sit a strait edge across it and check it from front to back. We had a brand new one that we spent an hour "fixing" one time. They just suck.

 

Noone ever metioned putting a thin coat of grease on the seal surface. I think my manual even says to do this.

 

credit given to damon