After installing my new end links I decided it was time to pull the aluminum radiator, drop it off to be repaired, and replace a leaking front main. The rad shop showed me where the leaks were and said it has to be epoxied. I've never heard of this before. I'm used to having the older style copper/brass units. Anyway, they  are working on it now.

I removed the crank damper and could clearly see where the leak was at the main seal. The whole front portion of the engine is pretty grungy from leaking for a long time. I did clean it up a little. The front main seal came out super easy! Cleaned the matting surface and installed a new seal. Was definitely tighter than the old one. Put the crank damper back on and torqued the bolt to 105 ft lbs.

There is one thing that is now bothering me, of course after the fact. The woodruff key was cocked at an angle (in the crankshaft) when I removed the damper. I was able to remove it fairly easy. And could put in place fairly easy with a magnet and my finger. So I looked at my "How to rebuild your Datsun" book and I see they had to remove it with a screw driver and mallet. Should I be concerned about mine being loser? It's a poor pic but I think you can make out the woodruff key is sitting cocked. Let me know what you guys think.

Edited March 2, 20187 yr by rcb280z

Won't the damper slide over that and hold it in place?

27 minutes ago, siteunseen said:

Won't the damper slide over that and hold it in place?

That's what it did. My concern is with how "loose" it is in the crankshaft slot. I can slide it back and forth fairly easy. I don't feel any side to side movement. I was just concerned when I read how Tom Monroe said to remove the woodruff key. But if you guys think I'm concerned for no reason, let me know.

Edited March 1, 20187 yr by rcb280z

The Woodruf key, I if  Iam not mistaken has a bit of a "BOAT SHAPE" to it. It appears at the angle you have it at there is a possibility it will not hold the balancer in place. I would give it another try. The ease of removal was because of the presence of oil. That key should have the flat side outwards but the flat surface should be as parallel as possible to the shaft or at least that is what I would aim for to ensure it doesn't undo itself. Give it another try for everyone's sake! If it comes off your radiator repair would be pointless!

58 minutes ago, esmit208 said:

"BOAT SHAPE"

Right. So maybe there is a reason for that rounded side of the key.(?) Just in case of movement, if it moves a little it will still seat? I tried again. I think the same thing happened but can't be 100% sure. Its locking in place, just not sitting in the crankshaft slot like I think it should be.

I looked at the How to rebuild your Datsun book again and see Tom tapping the key into place will a piece of wood and a mallet. I did NOT have to do that. There was no noticeable damage to the key slot in the crankshaft that I could see. Looked normal. So I'm not sure what to think. 

Okay, it just dawned on me that it's been sitting like that for many years. The pic I posted was what it looked like after I pulled the crank pulley this morning. The last time the pulley was off was in 1995 when I had to replace it with a good used one after it separated. It probably happened then and has been that way since.

Edited March 4, 20187 yr by rcb280z
corrected when the crank pulley was off

Seems like the rounded bottom allows the key to be tilted towards what is being slid over it. Once the part is in place the key would sit level.

 Cliff's got it right. The key is installed tilted just enough to allow the h-balancer to slide onto it easily. The key will rotate as the h-balancer is slid over the key. I think I'd use a dab of blue tread locker on the key but in reality the key can't come out once it's been installed. 

Well guys it's a good thing I decided to take it back apart. As you can tell in the pics I have parts to order Oil slinger looks bent.  What a bummer!

Edited March 2, 20187 yr by rcb280z

I . the key is available at any Nissan dealer for like $3, Tell them its for a 300zx

2. A new alum radiator(3 row) is like $125 delivered to you house, cheap insurance, a bad epoxy job will result is a head gasket job(or worst), not worth the risk.

I’ve always lubed mine when I put it in so it can pivot easily. It’s not going anywhere.

What year is your car? I may have an extra balancer I would sell you. 

Radiator is already repaired. $40. 

Thanks for the offer Jeff, parts are already on their way.