Some of you know I had a slight oil leak from the rear of the engine. I pulled the transmission yesterday morning (not a nightmare as I thought it might be). About 3 hours.
Anyhow, Yesterday, I removed the rear engine case to clean up the sealing surfaces in preparation of reinstalling. After cleaning the surfaces with my angle grinder and rubber gasket surface cleaner (think of bunch of little green rubber erasers spinning on the end of a small angled-die grinder - it is very gentle. (will post a picture) AND using a razor blade in the spots I could not reach with the die grinder, I prepped the surfaces. From there, I used acetone to clean all of the surfaces. This took a long time, maybe an 90 minutes.
I was then at a crossroads - I wanted to install and keep moving. I emailed Dave M. for advice. He hasn't done this job yet, UH OH. So... I called Jono.
Jono's advice was to:
1. He said to use the black Mercedes sealant or "The Right Stuff", which he said is the same. I had bought the black Mercedes sealant a month or so ago anticipating this job. 003.922.214.171.124.
1B. take your time. he said it won't skin over quickly.
2. apply a thin coat of sealant to both parts and be prepared for a fight getting the cover in place as the tolerances are very small without sealant. I did that. WOW - my hand was shaking from pushing the piston in the sealant tube after a while. Anyways, I laid down a bead about 1/16th" on both sealing surfaces, surrounding all of the bolt holes, etc.
3. Jono suggested to apply a little more in the corners where the block, engine cover and oil pan all meet. I was anticipating this ..... cool, I think I'm on the right track
4. when it came time to apply the crank lip seal, he said to oil the inside of the seal (against the crank) and carefully install it to the same depth as the old one. He said this would be quite hard to do and the seals often put up a fight. Initially, mine did too. The inner lip was folding under. I took my finger nail and worked around the inner lip outwards, giving it room to clear the crank sealing surface. Once the inner lip had completely cleared the crank all the way around (and was not folded under), I slowly began to tap the seal into place with a rubber mallet. He suggested using a block of wood. I did that as I came close to the end. This allowed me to push in on several inches of the seal at the same time and working around, I made sure it was properly and evenly seated. The finished depth is a hair (enough to catch your finger nail on but not much more) above the surface of the engine cover. To the casual eye, it'd be flush. I almost think this is impossible to screw up, because the seal sets against the housing itself. The old seal was bottomed out.
Well, wish me luck!!!
A few other random notes:
1. torque the bolts in stages. It doesn't take much torque 9Nm. I worked my way around the bolts probably five times gently getting more snug. T
2. squeeze out was minimal, so that appears promising.
3. I had a hell of time removing the old seal from the rear cover. I realized whoever installed it used sealant around the perimeter of the lip seal. I had to heat the cover around the seal before it'd come out.
4. the factory service manual calls for starting the engine before re-installing the transmission. Not sure how I could do this. I need part of a bellhousing to install the starter. Don't suppose that is easy to come by!
5. I've used a very a very similar sealant to this black sealant when reinstalling my trans oil pan on my landcruiser. It sticks like tar and while messy just plain works. I'm hopeful of similar results! I'm 99% sure Toyota and Mercedes use the same product. Of course, Toyota also labels it as their own.
6. I bought the repair version of the seal, which offsets the sealing lip in a different location from the original. Not sure if this was necessary (no groove on the crank), but I ordered that one ahead of time. It really shouldn't make any difference.
7. the rear engine cover overlaps (has a bigger footprint than the sealing surface on the block). Once cleaned up, dry fit the cover and run a permanent marker around to scribe a line on the engine case. You'll then know where to apply the sealant. I did not do this and didn't think of it until after. But, I did apply sealant to both parts, so hopefully, it will still be sufficient.
Next up, waiting on some seals to seal up the external portions of the transmission. And will change the steering idler while access is free and easy (no exhaust).
DID I MENTION: WISH ME LUCK!! SURE WOULD HATE TO DO THIS OVER.