Nose Bearing O ring

[Charley]

Can anyone tell me where the round spring-like “O” ring goes in the number 8 nose bearing? It fell out of the bearing when I took it off the crank shaft. I can’t find any pictures of it in my manuals. I’ve got the outer O ring and pulley seal, but I can’t find a place for the wire/spring O ring.

[Wayne 962]

Page 129/130 shows the black o-ring in the nose bearing (Engine Rebuild Book).

-Wayne

[Wayne 962]

Wayne,

Thanks for your quick response to my posting about the o-ring. The attached picture shows the spring-o-ring in the foreground (the image is too big for the forum). Since I can’t find it in your book or my manual, I’m wondering if it belongs?

BTW – great website and you’re Rebuild Book is a great help!

It looks like you're slightly confused. From your picture, I would assume that the black o-ring (I added an arrow) is what you're looking for. Check the pulley seal carefully, your small spring should be inside of the pulley seal, not outside, sitting on your counter.

See the pages in the book, and you will see what I mean...

-Wayne

[john walker's workshop]

i would suggest using a red oring from a SC instead of the black one.

[Wayne 962]

Originally posted by john walker's workshop
i would suggest using a red oring from a SC instead of the black one.

Why?

-Wayne

[thor]

generally I thinks it 's recommended to use a o ring from turbo which is more resistant in the time ? no?

[john walker's workshop]

they're a tad thicker and they stay pliable, unlike noeprene (sp) which gets hard over time. i'm assuming the black ring is neoprene.

[Wayne 962]

[edited - hmmm I must have been thinking of something else] Did they supercede the o-ring to a newer style? I had not heard this...

-Wayne

[Tim Walsh]

Umm.. the nose bearing isn't the same across all years. The SC bearings DON"T fit Mag cases. They're a couple mil larger in diameter. Just enough not to work.

Don't ask how I know (lost a whole weekend of work to this)

When it comes to the o rings and seals I can't say one way or another.

[john walker's workshop]

the extra thickness gives you a bit of extra crush for sealing this often leaky area. extra insurance. it fits the early nose bearing just fine.
SC and up 999 707 285 40
up to 77 900 174 041 40

[Eagledriver]

I tried using a bigger O-ring that I had from a 3.2 gasket kit on my 2.7 rebuild. It was black and I can't be sure it was the one for the nose bearing but it looked right and was only a little thicker than the 2.7 ring. It was a big mistake...the ring sqeezed into the case and kept the case halves from mating tight. If I hadn't caught it and redone it I would've had a massive oil leak similar to the one that has been talked about so much on this forum.

-Andy

[john walker's workshop]

probably because it was hard black noeprene. the softer red ones don't do that. been using them for years. or it may have been the wrong one.

[Charley]

Thanks for all the responses. I'll most likely stick with the standard black o-ring (it's already purhcased). I'm looking forward to completing this phase of my project this weekend!

[Alan Cottrill]

Whats that pin next to the nose bearing in the picture?

I don't remember removing one of those.

is it the alingment pin in the case?

I'm really sweating this!

[john walker's workshop]

it taps into the case and properly positions the nose bearing. it seems there's always something that you think back on, and say, oh my god, did i do that?

[Alan Cottrill]

Thanks John.

I get that feeling about every day...did I remember this...did I do that?

I don't think It's going to go away until it runs.

[tgarnoldo]

Believe me, it takes more that to have it just running. I finished my rebuild in November and now have just completed the 500 mile oil change and valve adjust. All looks good and sounds good, but I'm still not 100% comfortable. There was just a touch of filing on the drain plug magnet, I assume (hope) this is normal...

Arnie

'87 Carrera
'01 Beck Spyderr
'96 BMW 328

[Wayne 962]

Originally posted by tgarnoldo
There was just a touch of filing on the drain plug magnet, I assume (hope) this is normal...

Very normal...

-Wayne

[cstreit]

Wayne's right. Remember if NO metal came off anywhere, the engine isn't wearing and would last forever...

[magic930]

Charley not sure if anybody answered your original question. The "spring like metal ring", is part of the front oil seal, its slips over the lip on the inside. Be careful when you slip the bearing back on the crank, press gently... if the lip curls back the metal spring will come off an yo won't know it until oil starts leaking out!