that seal doesn't look right to me - is it the same size as the timing cover hole? 

You can still purchase Nissan OE seals. I like to go OE whenever that is an option.

I followed the above and was able to  remove the old seal....but i am confused badly. Let me give some more info and images. In comparisons image you can see the old seal and the new one i just got. New has a metal ring around it. old one doesnt. However if you look at close up image you will see a metal ring around crankshaft. Is this from the seal? is this something else that should stay in and the seal go over? I dont see any way to take it off either. In close up #2, there is a small key channel to right of key, but it is SMALL and will not slide over key and i can't seem to get key out. Key looks fine although i do have a new one in case.

  

yikes, turning into a cluster. Not sure what the that chunky looking stuff is, second to last pic. is that gasket material? hard to tell what is going on. I think I see the oil pump drive in the 1st pic. the last pic looks ok, but that second to last is just odd.

You have a badly positioned key, slinger looks damaged. I would be tempted to just pull the cover and start all over. Making sure the key is correct any junk left over from the old seal is out and take a close up look at the slinger.

Edited March 9, 20214 yr by Dave WM

I agree, think that timing cover is going to have to come out to remove the debris and straighten the key. 

You can buy a new key, they're around, and cheap.  Wrap some tape around the snout so you don't gouge anything and rip that key out of there.  Then get some bright light and magnifying tools to see what you're working with.

https://www.amazon.com/Nissan-00926-51600-Genuine-Crank-Woodruff/dp/B013EWNDRC

http://www.carpartsmanual.com/datsun/Z-1969-1978/engine-240z-260z/piston-crankshaft/10

http://www.carpartsmanual.com/datsun/Z-1969-1978/engine-280z/piston-crankshaft/10

thanks. whats 11, 12and 13 on the exploded diagram.

TC sprocket, oil pump drive, oil slinger.

ok. was hoping this dang seal was pictured on there somewhere....i am still not 100% on exactly where it goes.. i assume b/t 16 & 12

 

i will take the timing cover back off and get some images and upload in a few days. thanks guys

 

@Wally You should consider getting a copy of Tom Monroe's book, How To Rebuild Your Nissan & Datsun OHC Engine, if you don't already have it. Lot's of detailed assembly instructions and pictures. 

https://www.amazon.com/Rebuild-Nissan-Datsun-Engine-Publisher/dp/B004X9A0OA

I had a motor failure a long time ago resulting from a recip A/C compressor causing uneven torque pulses on the crank snout.  The harmonic damper's woodruff key wallowed out the keyway.

Rather than weld up and recut the woodruff groove, the machinist suggested cutting one continuous key way and using one long straight square key.  Perfect!  It solves every problem with woodruff keys and presents no problems I've yet to encounter.

I know this doesn't help much unless you end up with a bigger problem.  🤯

Edited March 10, 20214 yr by ETI4K
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