I have spent more time trying to get the rear main to stop leaking on this tractor (1955 FORD 640) than I have in rebuilding the rest of the tractor. When I tore it apart it had a rope seal in it. I have tried the Fel-Pro and Victor seals.
None of the neoprene seals seat in the block. They will seal in the cap but not the block. The seals leave a gap between the block and the seal mating surface. They fit the crankshaft fine, but do not seal in the block. I have no problem getting the cap side packing sealed and have no leaks at the cap/ block interface.
On my last attempt I made an aluminum shim to place in the block to take up the extra space between the neoprene seal and the block surface and used the Victor Bead n Seal to seal the crankshaft seal in place. I used HOBO s trick of air pressure and soap solution to check for leaks. NO leaks. Drove the tractor around the fields for an hour and a half and now I have a rear main seal leak.
I stopped at a nearby New Holland Dealer and talked to the old timer mechanics working there. They said they had seen several neoprene seal failures as they were not designed for these old tractors and to go back with the rope seal.
OK. Now back to the original question. Which rope seal do I use? I can get one from YT which is probably a Tisco or other. I can order one from New Holland or I can get a Best Gasket (located in California) and get their Graph-Tite rope seal. Which one would be best, as I have it in me to redo this rear main just one more time.
None of the neoprene seals seat in the block. They will seal in the cap but not the block. The seals leave a gap between the block and the seal mating surface. They fit the crankshaft fine, but do not seal in the block. I have no problem getting the cap side packing sealed and have no leaks at the cap/ block interface.
On my last attempt I made an aluminum shim to place in the block to take up the extra space between the neoprene seal and the block surface and used the Victor Bead n Seal to seal the crankshaft seal in place. I used HOBO s trick of air pressure and soap solution to check for leaks. NO leaks. Drove the tractor around the fields for an hour and a half and now I have a rear main seal leak.
I stopped at a nearby New Holland Dealer and talked to the old timer mechanics working there. They said they had seen several neoprene seal failures as they were not designed for these old tractors and to go back with the rope seal.
OK. Now back to the original question. Which rope seal do I use? I can get one from YT which is probably a Tisco or other. I can order one from New Holland or I can get a Best Gasket (located in California) and get their Graph-Tite rope seal. Which one would be best, as I have it in me to redo this rear main just one more time.