Lucy’s been leaving her mark at every parking spot she’s visited for the past few months. When the excessive leaking first started, I had carefully tried to find the source, and had visually ruled out the oil pan and valve covers. I’d also looked as closely as I could at the ends of the push rod tubes and had felt they were not the cause. My view was hampered, however, by the exhaust manifolds. All that left, I deduced, was the top engine cover. To replace these gaskets is quite the project since it requires removal of much of the stuff on top of the engine. Even though I already have the replacement gaskets, I didn’t have the time.
This weekend my plan was to replace the head gaskets on Glinda, but I’d waited too long to order the new parts, so they haven’t shown up in the mail yet. With some garage time available, I pulled Lucy in and put her rear up on the ramps to see if I could verify my previous diagnosis before starting the project. After wiping away oil and grime from as much of the bottom surfaces as feasible, I found that the main source of the dripping oil was too far outboard to be the top cover. It had to be the right side outer push rod seals – the ones whose view is blocked by the exhaust log. So I removed the right side exhaust assembly to get a clear view, and, sure enough, the oil emanated from the tube joint.
I had a half set of Viton o-rings on the shelf – enough to re-seal one side of the engine - that I’d been saving for Glinda’s head gasket job. I decided to use them on Lucy instead and try to get more new ones from the local Corvair guru’s stash of replacement parts.
So, down off the ramps rolled Lucy, and up on the jackstand went her right rear corner. With all the motor oil on the left side, I removed the right side’s valve cover and only a little bit of oil dripped into the drain pan. I could now easily see how much the tubes moved indicating failed o-rings. To get the tubes out, I had to remove rocker arms, push rods, rocker studs (which are also head nuts) and push rod guides. This needed to be done in pairs since each guide covered two tube ends and I didn’t want to remove all the rocker studs at once. I decided to try something different when removing the rocker arm retaining nuts. I didn’t want to go through the manual’s procedure of setting valve lash, so I counted the number of revolutions it took to bring the outer face of the nut flush to the end of the stud. Since I wasn’t changing any of the stackup of parts, I knew that screwing the nut back on the same number of turns would give me the proper lash.
The first pair of tubes came out easily once I tightened a holes clamp around each one to give me a safe point to pry against. I found that whoever did the last re-seal job, mixed o-ring materials. The outer rings (in the hotter head) were the red silicone, while the inner ones (cooler block) were the stock black rubber. I replaced all, including the o-rings under the rocker studs, with brown Viton. Everything went according to plan, and after torquing the valve cover retainer bolts to 50 in-lbs and mounting the wheel, I lowered Lucy to the ground. The moment of truth followed when I started the engine up, and happy was I to not hear any clickety-clack of loose lifters.
When I pulled Lucy out of the garage to park her on the street, I found an oil-free spot to center the engine over, so I’d have an indication of the success of my endeavor. When I came out the next morning to drive her to church, there was just a tiny spot of oil on the pavement. Yeah!
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