Gidday all,
I am about to replace the rear crankshaft seal in my 71 ambo(302). Does anybody have any advice on fitting the rope seal correctly as I have never done one and been told if its not fitted correctly it will leak badly? Also Im after bottom end torque settings(mains,big ends etc). Any help anybody can give would be greatly appreciated.
Thanks
Kel (Australia)

 

Are you actually using the rope seal, or do you have the replacement rubber split-lip seals? If so, there's a little spike inside the bearing cap to hold the rope seal in place that needs to be removed and the hole filled with a drop of silicone sealer. Also, make sure the seal lip is facing into the engine and stagger the seal halves by about 3/8" rather than installing them with their ends flush with the block and cap. Put a little oil on the lips of the seal where they ride on the crank but don't get any on the mating surface between the block and the cap. You'll need to put a little more silicone there to seal that as well, but go sparingly, a very thin film is all that's needed.

If you are actually using a the rope seal, press it into place in the block and roll a large socket along it while tapping gently on the socket with a hammer to help press the seal into place. Don't stagger the ends like you do with the rubber seal, and when it's well into the groove trim off the excess material with a razor blade. Do the same with the cap, although it's a little tougher to handle since it wants to move around on you. You can put it in a vice, but do so gently, you don't want to distort the cap.

Again, use a little sealer on the cap/block mating surfaces as I described above.

Install the bearing and lube it up at this point, then set one edge of the cap into the groove and tap it sideways against the block and tap the other side down into its groove while keeping an eye on the outside surfaces to make sure they're flush with each other. When the cap is seated, then put the bolts in and run them down, alternating between the two till they're snug. Torque to 60-70 ft-lbs.

Just for the heck of it, I'll include instructions on seating the thrust bearing.

Tighten and torque all the mains except the center one, just seat it and snug the bolts and then loosen them a tad. Pry the crank gently back and forth a few times with a large screwdriver or small prybar, and then hold it forward while you torque the center cap bolts.

Once all the main caps are on and torqued, put the dampener bolt in and turn the crank with your torque wrench. Expect 10-15 ft-lbs of torque to turn it with the rope seal but no rods bolted up. With the rubber seal, it will be considerably less.

Big-end (rod) nuts torque to 19-24 ft-lbs with stock bolts, manufacturer's specs for aftermarket bolts.

Hope this helps...

 

Thanks Dan,

I appreciate your help on this one mate.
Regards
Kel