The Stovebolt Site Forums The Shop Area Engine Shop 235 up and running....

My rebuilt '59 235 is installed in the truck and running smoothly.

Now for the bad news. I'm chasing leaks. Several of them! :mad: My initial reaction was a big let-down when I saw oil puddling under the rear main seal. Then I searched and read the posts on this site and I started looking more carefully. I'm still worried about the rear main seal, but it appears that at least some of the oil leak is coming through the valve cover gasket. I see traces of oil on both sides of the engine near the top. I guess this should not surprise me. The oil pump is delivering a lot of oil up top. So much so, I can't run the engine with the valve cover off, because oil squirts out the rockers and over the edge of the engine.

My question is, what should I do about the leaking valve cover gasket? The gasket is new and the cover is tightened down about as far as I feel comfortable (afraid of stripping the screws). I installed the gasket dry. Should I use silicone sealer on the gasket? Can I do this once the gasket is saturated with oil?

I also have leaks appearing under the tranny (SM420, 4 on the floor). I assume this is gear oil but I'm having a hard time telling the difference between engine oil and transmission fluid. The transmission was professionally re-built before the installation. I see plenty of oil way back at the universal joint. Maybe that is where the leak is coming from??

Which leads me to my second question. The universal joint (at the rear side of the transmission) has a separate fill-hole for gear oil. However, the shop manual seems to suggest that the universal joint receives its oil from the tranny. So which is it? Is there a separate reservoir of oil in the u-joint, or does the u-joint get all of its oil from the tranny? Is the torque tube seal at the universal joint a place where others are experiencing gear oil leaks?

Thanks! The help I've received from all of you has been priceless (in more ways than one!)

The procedure for selecting the correct number of ball/bell-collar seals is nicely described in the Shop Manual. How did you go about selecting how many seals to use - too many and you leak; too few and you loose the ability to easily move/rotate. This location should not leak much (no more than a few drips every time you stop).

Another common location for a little leaking is at the collar/cover at the rear of the u-joint ball/bell. The seal at the rear of the collar, around the torque-tube, seems to be a place to expect a few drips at every stop.

The u-joint does receive lubrication from the transmission; however, people have reported using the separate fill hole (that you describe) as a way to put a little lubricant into the ball/bell.

Did you check to see that the bottom edge of the valve cover produced a flat surface all around the base, and were the areas around the screw holes in the valve cover flat or indented downwards? I cement the valve cover gasket to the bottom of the valve cover.

It sounds like you may have the wrong rocker arms, if oil is squirting out of the rockers vent hole.

1959-62 rockers should have the groove offset 1/4" inside the rocker so it does not line up with the supply hole.

If you do have the right rockers another problem could be the rocker shafts could be the type with a flat spot ground the full length, which ends up giving the oil to easy of a path from the supply hole to the groove and out the vent hole.

It is also possible you have the shafts on upside down which will also produce to much oil.

Pre '68 Dave - The rocker arms are rebuilt originals out of my engine, so I'm sure I have the right rockers. However, you might be on to something... probably another rookie mistake I made. The shop manual shows a clear diagram of how oil is pumped up the center gallary to the top of the engine. However, once the oil gets to the top of the head, I don't understand how it gets into the rocker shaft. There is a short, C-shaped brass tube in the center of the rocker. I assumed this tube transfers oil from the oil gallary into the shaft. On my engine, it fit perfectly, so that's the way I installed it. Maybe I have this wrong, and I'm supplying way too much oil to the rockers?? The shop manual is not clear on this (at least not clear to me).

TC - I will check my valve cover for warping. The torque tube seal I'm talking about is what you are calling the collar/cover on the u-joint ball/bell. I drove the truck for 5-10 minutes. The next day, there was a teaspoon or two of fluid on the garage floor under this joint. I will review the shop manual and my photographs again. It's been over a year since I assembled this joint. If there is another seal inside, I can't remember where it is or how I assembled it.