Has anyone recently replaced a rear main rope seal? When I bought my car the rear main seal had been replaced with a split neoprene/metal seal. Later I obtained a parts engine and removed the rear main seal bracket. It held a cork seal about 0.250 inchs wide and thick. I purchase a rope seal for it, but it is much thicker, at about 0.350 inch. Should I obtain a smaller size rope seal, or stuff the one I have in the bracket? I have never seen a correct rope seal bracket and would like to know how large they are. ???
I have never replaced a rope seal before but with modern style seals if it clamps on the shaft to hard it will generate enough heat and melt it.
I guess with rope style seals, they require a certain amount of crush for sealing life. But a 2.5mm (sorry i work on the metric scale) greater thickness might put to much pressure on crank and cause excessive heat. Possibly causing early failure.
Hopefully someone can give you a better answer.
Ian
You should stuff as large a diameter rope seal in there you can get in. Smearing on some modern silicone grease,both on the seal surface and on the cavity surface, helps get it placed right and keeps the 'burning' down until it seats. The rope seal will take up the shape of the cavity it's stuffed into so it should be somewhat tight to get in for a good seal. Also a little long as the ends have to jambed together for a good seal as well. (I couldn't believe my eyes at a fleamarket about a month ago. This guy had 2 huge original rolls of rope seal. Two different sizes. He charged a $1 a foot so I bought a bunch for stock.)
I have replaced rear main seals before and you do need to pack then in tight ! This also means more drag on crankshaft , I prefer the neoprene seal as it has far less drag and less heat buildup ,if rope seal is to tight it can burn seal and leak to loose will also leak !
Choice is yours !
Cheers Tony.
I have re-built too many engines to count, with rope seals and have never had one leak.. I always leave the rope a 1/4 inch long on each end, top and bottom, kinda push this 1/4 inch back into the cavity without really packing it hard, then tork the main cap to specs. I even put the rope seals in without pulling the engine or crankshaft. We had an item we call a "Chinese finger lock". It is made of stainless steel with a cable long enough to feed through, over the crank shaft, then put one end of the seal in the Chinese finger thing and pull the seal through. Works real good, and I bet you can still get one at most parts stores.
I would trust the rope seal more than the neoprene type. I never worried about packing the seal more than just the normal installation in the cavity. To every man his own thou. lol Good luck.
SDGlenn