Engine/Transmission (1994 - 1998) Replacing tappet cover gasket hints

[GAmes]

I need some. I replaced the gasket while the engine was out of the truck. I used 3M black super weather stripping adhesive. The thick part of the gasket was inboard and the tab that says "FRONT" was in the front. I let the sealant cure overnight before I bolted on the cover. It leaked, and not just a little seep, a real aggravating, uses a lot of oil leak. So I have the cover off again. The head and IP are off so I can easily see everything. What do I need to do to make the job work this time? The last time I put the sealant inside the groove before I installed the gasket. Perhaps I need to install the gasket, then put a bead of sealant on the inside edge?

 

[NIsaacs]

I have not ever done one so I can't help much. Do the hold down bolts have a shoulder or something to limit their travel? Maybe add a washer to get more compression on the cover. Also high temp RTV sealant would be my choice, on both the block and the cover. Snug the cover bolts down finger tight, no tools. Let it set about 30 minutes, then bolt it down.



Nick

 

[GAmes]

Here are a few pics. The brown side is the outside with the foam insulation removed. The yellow is the inside. Also shown is the hole in the side of the engine that it covers. As you can see, the hold down bolts are in the center. They have rubber coated washers for sealing. The gasket fits around the ouside. It has a slit that the edge of the cover fits into. The force of the 6 center bolts push the inside of the gasket against the block. Seems easy enough, but it has me whipped. The 3M sealant is a recommendation from Joe Donnelly.

 

[NIsaacs]

Just a thought, since the last time you changed the gasket and it didn't help, I wonder if it is the head gasket all along, the oil orifice to the rockers are on that side, close to the edge of the block. I am sure you have sealed a lot of gaskets with no issues so.....



PS: after you explained the gasket, it makes sense to use the 3m so it don't mush out of the slot.



Nick

 

[GAmes]

Just a thought, since the last time you changed the gasket and it didn't help, I wonder if it is the head gasket all along, the oil orifice to the rockers are on that side, close to the edge of the block.

Believe me, I have considered that. But since I have a habit of cleaning the engine before I pull it into the garage, I don't know. I didn't want to say it out loud either, sounds too strange. :-laf

 

[BigPapa]

What's up Gary?



I did mine while I had my engine out also. Used the yellow 3M Weatherstrip Adhesive on mine. No problems. Have you checked to make sure the vent is still breathing? If it's stopped up crankcase pressure could push the gasket and oil out.

 

[GAmes]

Scott,

I think the key is how the weatherstripping is applied. I'm thinking that by forcing it into the crack of the gasket it deformed the outer surface enough to make it uneven. How did you do it?



The vent is clear.



Gary

 

[BigPapa]

I just stuck the nozzle of the tube in the channel of the gasket and laid down a bead, then put the gasket on the cover. Had some sealer squeeze out from under the gasket on both sides in a couple of places but it was very minimal.

 

[GAmes]

Thanks, guess I'll give it another try after I check for a straight edge on all 4 sides of the cover.

 

[BigPapa]

I was trying more to glue the gasket to the cover than to help seal anything. I actuall let it sit and cure for 24 hours before I installed it on the engine.



Who knows, maybe it's just that you used the wrong color gorilla snot... ... ... .

 

[hsmith]

Learned a trick years ago working on steam units. Had to make a lot of gaskets and use gorilla snot, yellow. Put down a bead, apply the gasket, press down, then lift the gasket for 10 secs or so to let some of it air dry. Then replace the gasket and let the glue cure. Seems to really help holding the gasket in place. Use the same method today, just can't get my tech to understand the principle.

 

[BigPapa]

Yes, forgot that part. I let it "breath" for @ 5 minutes before putting the gasket on the cover.

 

[Bill Stockard]

Learned a trick years ago working on steam units. Had to make a lot of gaskets and use gorilla snot, yellow. Put down a bead, apply the gasket, press down, then lift the gasket for 10 secs or so to let some of it air dry. Then replace the gasket and let the glue cure. Seems to really help holding the gasket in place. Use the same method today, just can't get my tech to understand the principle.

Yep, I used the same stuff (we called it ol' yeller) and the same procedure when sealing the rubber rocker arm cover gaskets to the covers on big block GM gasoline engines to keep them from seeping/leaking oil.



Bill

 

[GAmes]

Thought I'd update this. I spent several hours with a bare block, a good light and a feeler gauge. I also managed to pretty much ruin a tappet cover, good thing I have two. :-laf I have decided that the main problem is the center portion of the cover gets bent in after a couple of installations and does not pull the inside edge of the gasket to the block uniformly. A couple good licks with a broad faced hammer to the mounting holes seems to be the answer. I can no longer slip a . 005 feeler gauge between the seal and the block, however I am still going to coat the gasket with "The Right Stuff" sealer when the engine gets assembled. I AM NOT REPLACING THAT GASKET AGAIN!!#@$%!#@$%!

 

[Nyoest]

I've never used anything except the gasket. Never had any leaks, but your bowed cover could be the culprit.

 

[GAmes]

I've never used anything except the gasket. Never had any leaks... ... .

Other than the sealer to hold the gasket to the cover, that is all I used. As a general rule, I never apply gasket sealer. But I tried two different covers with the same results. Attaching them to the bare block revealed gaps bigger than . 010 inch between the gasket and the machined surface. A straight edge confirmed the machine surface is flat. We can speculate why, but the end result is just installing the gasket will not always fix a leak. A little extra work may be required.