One piece oil pan gasket problems

[jrsauer64]

Working on a 99 Tahoe 4wd 5.7. I put a long block in it some time back and had a leak from the front of the oil pan from the start. Had someone redo the timing cover/oil pan last year and it went about 1-2 months before it started leaking again. Just replaced oil pan gasket myself and discovered that instructions (I should read more often) stated absolutely do not put an adhesive on the gasket. I had previously put a blob of silicone on the corners of the valley on the front (old habit from the multi-piece gasket days). The last guy that worked on it did the same but he gobbed it on (mostly to fill the hole in the timing cover that he somehow broke when mounting.

So this time I tried it dry. Replaced the timing cover and pan gasket and I'll be damned if it isn't leaking right from the front valley again. The pan was only mildly distorted along the straight edges when I removed and I straightened it. The valleys looked true and undistorted.

Addendum - Redid it today as notice a dent in bottom of front valley. Fixed it really well - all surfaces perfect and still leaked. Appears to be leaking at the corners of the valley. Instructions say DO NOT put silicone on gasket and yet still seems to leak from the corners at front valley.

Any suggestions on getting this to stop leaking?

 

[SouthJerseyTahoe]

when you say valley it mean under the intake manifold. that is the valley. if you're talking about the oil pan then yes you need to put a dab of permatex in the corners and i mean DAB. I use gray high torque on everything nowadays. If the pan has been damaged or warped then yeah i can see it not sitting correctly and not sealing especially if you had to do it on your back in the driveway. Confirm where the leak is coming from and get a new oil pan and clean the surfaces with a good brake clean or I even use gum cutter to make sure there is absolutely NO residue. Torque all the bolts evenly. Oil pans can be a bitch even if the vehicle is on a lift.

 

[jrsauer64]

One piece gasket problems

Yeah...I know what a valley pan is. Was just trying to describe the curved edge of the pan that goes around the bottom of the timing cover.

I cleaned both surfaces VERY well as I know what you are talking about but I didn't dab the corners as you described because the instructions said not to add adhesive and I reasoned that it was a one piece.

I didn't use die but I am 99% sure that it is leaking out of the corners after carefully watching it on the lift after installation. So my follow up question is do you dab both sides of the gasket in the corner when you dab (side facing block AND side facing pan?) or just one and if so which one? Thanks by the way.

 

[SouthJerseyTahoe]

If its a one piece silicone gasket you still want to put a small dab up on the engine in the 4 corners where the timing cover meets the block and in the back on each side of the main cap. You can see the seams if you look close. It should be a nice smooth curve on the pan side of the gasket so no sealer there. Oil will almost always find its was out those tiny little seams. It just happened to my other tech this week on a 4.6 Ford valve cover. He missed one spot and damn if it didnt come back leaking. Never coat a silicone or cork gasked with silicone as it will cause leaks. I start tightening the 4 corner bolts first just snug then the ones halfway down the oil pan and then just go around tightening all the bolts a little at a time. I have an inch pound torque wrench but dont really crush them down or you'll just bend the pan and squeeze out the gasket unless you have a good one with steel grommets around all the bolt holes.

 

[Bridgid]

Sorry to dig up an old post but I am having the same problem. Did you ever get it fixed? I have even gotten a new oil pan and timing cover. Last attempt to fix I used ultra black in the corners as all data says to and a thin bit across the bottom of the timing cover where it meets the pan.

 

[Bridgid]

In case some other misfortune person stumbles upon this. 3 felpro "dry seal" gaskets, a new oil pan, and a new timing cover later. .. There is a HUGE gap between the cover and pan. Had I not had an oil pan and cover sitting on the bench to see it I wouldn't have believed it. It's nearly 3/4 " the gasket doesn't come close to sealing that. Put almost half a tube of ultra black rtv in the timing cover where it meets the pan and finally no leak! Yay!