Is there a neoprene rear main seal for the 401? I am about to assemble a fresh motor and I expect it would be an improvement over the rope seal. Thanks Pat pmg455@rcn.com
Hey Pat yes there is a neoprene replacement rear main seal for our Nailheads but I can't find the part #'s for it. I think its the one for the V-6 motors but perhaps Jim will post which one he is using. You can also replace the timing chain cover seal with the 400-455 oil seal. Federal Mogul PN-474272 or CR 19786
All, I have in stock neoprene rear mains for the NailHeads. Also the front timing case cover seals. $25.00 rear main, $10.00 front. Tom
Thanks, I already have one. I'm just looking for some pointers on installation. I understand from further research that I will need to cut it down somewhat so that it is flush with the block and the cap. However, it seems like I should offset it once I do that so the seam of the seal and the line of the main are not together. Also, it seems like I should put a bit of silicone over the end just to give it hand. Does that sound about right? Anything else that should consider or do?
When using a seal that needs trimming provide about .020" interference on the ends. I always use the "trim ' seals when installing rears rather than drop in type. You can get them at any parts store, Caddy 472-500 motors.
Thank you sir. I definitely want to do this right the first time. Fixing a rear main once the engine is back in the car isn't my idea of a good time. Do you guys use any silicone on the ends?
Test fit the seal on the crankshaft to see if it fits with the sealing lips in contact and slightly folded.. Then install the seal in the block and/or rear main cap and push on both ends to see if it will fit flush. Install or trim as necessary.
