I just received my front and rear covers with newly pressed in oil seals. When I took them in to get pressed in, I definately remember that the old ones were set flush in the covers from the factory. I picked them up the other day, and both sides were recessed as far as they could go. I took them back with concern as to why the seals weren't pressed in flush. The owner told me that he pressed them in as far as he could to prevent any leaks. I mentioned to him that they were flush pressed when I brought them in. I wanted the shop to replace the seals with new ones and have them installed correctly. He told me that they were installed by the correct procedure. He mentioned that the factory front and rear surfaces of the crankshaft usually have grooves worn into both front and rear surfaces that micropolishing can't rememdy, thus he recessed the seals to prevent oil leakage. Lastly, if I wanted new seals installed, he would have me sign a waiver stating that his shop wouldn't be held accountable.
Tell me who is right. I let a friend borrow my FSM, and he is out of town so I can't reference it. HELP!

Rob

Flush is the correct way.

I took the front main and rear seal covers to 2 different Nissan dealerships. I spoke to the head mechanics in both stores. I showed them the seals and how they were recessed mounted. The first guy asked me "Was I still using the factory crankshaft?" I told him yes and he said that the rubber seals actually wear a small undetectable groove in the front and rear of the crankshaft. You can feel it if you run your fingernail over the shaft surface. If the machine shop would've installed it flush, it would've surely leaked. The other HM said the EXACT same thing. Now we know. Anyone care to argue?

Rob,
Not trying to argue or anything, true that the rear main rides on the back end of the crank. But doesn't the front crank seal ride on the back of the crank pulley, not the crankshaft so if recessed too far back might be a space between the rear edge of pulley and seal(never really measured how far back the pulley went-just a thought).
W/new seals installed flush, won't the springs in the seals compensate for the wear of the groove if not too deep.
Chris

That's what I thought and argued with the machinist. The two HM's at the dealerships assured me that the seating was done properly. Their reasoning was that the space allowed for repositioning the front and rear seals to compensate for wear on the crankshaft ends.
That's the best way I can explain it. Three people can't be wrong.

is that like the 2 wrongs dont make a right but 3 lefts do?? theory..

Well Rob,
I hate to say it, but I guess you will find out when you get it running-Hopefully it does not leak, front isn't so bad, rear:eek:
Is your car going to be an ALL-OUT drag car? (wheelie bar and all!)
Chris

Originally posted by Projnx2000
Well Rob,
I hate to say it, but I guess you will find out when you get it running-Hopefully it does not leak, front isn't so bad, rear:eek:


If it does leak, I'm kickin' somebody's ass! I'm talking about an old school beat down. I spoke to a fourth! guy at another machine shop this afternoon. He said the same damn thing. The actual seal wears a groove into both front and rear surfaces.
The car isn't going to be a full blown drag car, yet. I don't have the resources (read MONEY) to travel coast to coast without major sponsorship. For now, I just want to kick some Midwest ass.

I just installed a rear main in my B13 and I got the seal from the Nissan dealer. The new seal was narrower than the old. I installed it flush, and noticed the big gap, under the seal. I called 2 Nissan dealers, and they said install it until is bottoms on the seal retainer. They stated the same reason you explained. I haven't got it running yet, so not sure if it is gonna leak or not.

I installed them flush in my DET with absolutely no problems.