Thread: Replacing oil pan Gasket

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Have a 1968 Chevy C-10 pick-up truck with a 327 and 400 automitic transmission. The oil pan gasket is leaking and I need to replace it. What are some hits about it. I have a book and it shows a way to do it. But I,ll bet some of you guys have a better way. Thanks, John.

I can't remember just what the books show, but I can tell you how I came to do this. First of all, you may have to raise the front of the engine to clear the front crossmember; if so, you will most likely have to remove the distributor, road draft tube, and oil pressure sender, for firewall clearance, and disconnect the throttle linkage from the pedal arm. Drain the oil, remove the flywheel cover, unbolt the oil pan and drop it out.

Clean the gasket surfaces on the block and oil pan well. Use a small hammer and dolly, or some sort of flat bar stock to back up the hammer, and flatten the dimples around all of the bolt holes on the pan flange. Apply a thin coat of non-hardening gasket sealer to the block and the pan on all of the gasket mating surfaces. get four or six 1/4 - 20 bolts or studs, at least one inch long - if bolts, cut the heads off and file the cut end smooth - and screw these into two holes in the front, middle, and rear of the block. Slide the cork, or flat rail gaskets over the studs and stick them to the sealer; install the front and rear rubber seals in place (the sealer is like a glue to hold them), then using the studs as guides, reinstall the oil pan, run all of the bolts you can up just snug, remove the studs and put the rest of the bolts in.

I don't remember if there is a torque value for the bolts given in the manual, but I tighten them with a quarter inch rachet and 7/16 socket, or use a 7/16 nut driver (half inch for the two front and rear most bolts) - starting at the middle of each side, and working toward the front and rear one or two bolts at a time, side to side, tighten them all just snug - where they give the same amount of resistance to turning - then go back and tighten them one quarter turn at a time in the same pattern; do this twice. Any more tightening than this will deform the pan flange and cause leaks. After the engine has been run for a few hours, you need to re-tighten the bolts, because the gasket will compress due to the heat and vibration; this may have to be done a couple of times.

Now, just put everything else back together in the reverse order you took it out, put in fresh oil and a new filter, check your timing, and ------

Yep like Rrumbler said. Wipe everything down with lacquer thinner, then a thin layer of silicone on the block. Stick the gaskets to the glue on the block and bolt er up!