Need Help with Oil Pan Gasket Leak

[derotoreut]

So I finished my 5.3L LM7 4L60E swap on my 70 K10 in the early summer. I drove the truck over the summer, but over time I was getting more and more dripping from around my oil pan. I rechecked the torque on the pan bolts and tried to snug it up a bit, but I think I may have made it worse.

My oil pan is one fabricated by Tilden Motorsports and should be a good pan. I tried to remove the pan, but even after jacking up the front of the engine I can't get it out. In order to get the gasket out I had to finagle removal of the pick-up tube with the pan dropped, but still in place. It looks like I'll have to replace the gasket with the pan resting on the cross member.

Looking at the pan, it appears that it may not be perfectly flat, but I can't tell for sure. I can't get any type of straight edge in there to check. I'm pretty much stuck using it, because I can't get it out. My question is are there any options for sealing it up better then the stock gasket. From what little I know, the stock aluminum o-ring style gaskets are supposed to be pretty good. In my case I had significant leaking mainly at the rear by the bellhousing. I also had leaking though at the front. Too much just to let it go. Any help is greatly appreciated.

[AussieinNC]

I have had "many" issues with fabricated metal pans leaking on these engines...to the point now where I wont use one....

Cast aluminum pan is the way to go....replacing the gasket on a pan that is not perfectly flat will only leak again...

One note...did you check the PCV system is working correctly and not allowing the engine sump to pressurize?

Hope this helps

[derotoreut]

Originally Posted by AussieinNC

I have had "many" issues with fabricated metal pans leaking on these engines...to the point now where I wont use one....

Cast aluminum pan is the way to go....replacing the gasket on a pan that is not perfectly flat will only leak again...

I would replace the pan if I could get it out, but I can't unless I pull the engine. I'm not going that route.

Originally Posted by AussieinNC

One note...did you check the PCV system is working correctly and not allowing the engine sump to pressurize?

How do you check this?

[derotoreut]

I know the stock gaskets are meant to be installed dry. Any issues with using a small amount of Permatex 82180 (Ultra Black Maximum Oil Resistance RTV Silicone Gasket Maker) along with it?

[ls1nova71]

You don't want any silicone on the gasket except where it's supposed to be, the 4 corners where the front and rear covers seams are. There's a place on the gasket for it, it has hash marks on it. Did you seal it there? Unfortunately, if you cant get the pan off, you probably wont be able to get the gasket around the pick up tube either, so if you didn't seal the corners, you should be able to do that by just dropping the pan as much as you can.

[derotoreut]

Originally Posted by ls1nova71

You don't want any silicone on the gasket except where it's supposed to be, the 4 corners where the front and rear covers seams are. There's a place on the gasket for it, it has hash marks on it. Did you seal it there? Unfortunately, if you cant get the pan off, you probably wont be able to get the gasket around the pick up tube either, so if you didn't seal the corners, you should be able to do that by just dropping the pan as much as you can.

When the new Tilden oil pan was installed a new gasket was used. That gasket was installed dry except for the 4 corners. They were sealed as required. I was able to get the gasket off by dropping the pickup tube in place. It wasn't easy. I'm going to try to get a new gasket back in the same way, then install the pickup tube again. I just don't have much confidence that it's going to seal and not leak. I think it's leaking because of the fabricated oil pan, but I can't get it off. I'd like to try using a light film of RTV, but I know it's not normally required. Would it hurt to use a light film of sealant? If so, then I'll probably install it dry again and hope it seals. If it doesn't then I'll have to pull the engine to replace the cover and gasket.

[87chevy.com]

Just take the motor mount bolts loose and rise the motor up a few inches to give the clearance needed to slide the pan out, then sell it and get a aluminum one..
Clint

[derotoreut]

Originally Posted by 87chevy.com

Just take the motor mount bolts loose and rise the motor up a few inches to give the clearance needed to slide the pan out, then sell it and get a aluminum one..
Clint

Thanks, but I already tried that. Jacked the motor up until the PS head hit the firewall. As far as I could go. There is still not enough clearance to remove the pan. It's too bad that the Tilden 4WD front cross member wasn't removable or able to be dropped.

[derotoreut]

So here's what I ended up doing today. I loosened the motor mounts and jacked up the engine until the passenger side head hit the firewall. It still did not provide enough clearance to remove the oil pan. So I decided to disconnect the oil pick up tube, so I could get a new gasket in around it. What a PITA.

I cleaned up both surfaces really well and made sure they were good and dry. Bought a new gasket and pick up tube o-ring. I slid the gasket into place and spent over an hour trying to get the pick up tube pack on. There just isn't enough room this way to do it (easily). I was able to get the pick up tube back into place, but I had to use the existing o-ring, because the new one was fatter and would not go on. The existing one looked in good shape. Hopefully it is.

I put a very, very light film of Permatex black RTV on the oil pan surface to hold the gasket in place. I then sealed the 4-corners as required. Got the pan back up and torqued all bolts to 18 ft-lb, except back wall two, which I torqued to 106 in-lb. I'll keep my fingers crossed and hope that it seals it. Being in Buffalo, I won't find out now until spring.

Oil pan dropped, but hits Tilden 4WD cross member.



Motor mounts loosened and front of engine jacked up as high as it could go. Still not enough room to remove the oil pan.



Oil pick up tube dropped down so new gasket could be installed.



Oil pick up tube back into place.

[AussieinNC]

If memory serves me right....

You can undo the mounting bolts that hold the Tilden crossmember into the chassis rails and slide it forward enough to give you better access....

Just mark the chassis so you can re align the crossmember after the move.

[derotoreut]

Originally Posted by AussieinNC

If memory serves me right....

You can undo the mounting bolts that hold the Tilden crossmember into the chassis rails and slide it forward enough to give you better access....

Just mark the chassis so you can re align the crossmember after the move.

Yes you are correct. Good point (if I ever have to do this again).

When I installed my crossmember I recall it fitting very tightly. It would need persuading to slide it forward, but I suppose it could be managed. Probably easier then removing the engine. Thanks for the input.