SM465 new mainshaft questions

I'm adapting a SM465 to a D18, and I just finished installing the new Novak mainshaft into the transmission. Now that it's all together, the mainshaft doesn't spin very freely. I can rotate it with a screwdriver, so it's not locked up, but I can't do it by hand. It rotated easily until I pressed the end bearings the last 1/8 inch into the case.

Is this a problem? Or will it be alright once some oil is run through it and its driven around a bit? If it is a problem, any idea what I did wrong? Does anyone have any input on this?

Thanks.

 

What is your endplay set at? I bought a kit a couple of years ago and had lots of nagging problems after the install.
I contacted Eric at Novak when I tore down the tranny again and found the tip of the shaft was boogered up. This was caused by the wrong spec in the installation manual regarding the proper endplay setting of teh mainshaft. Called for .012 and actually needed to be .002.
When I put mine back together (Novak replaced the damaged parts for free!!) I set mine up with .004 endplay and it felt tight. So far I don't get any binding like I did before.
If you installed new bushings, syncros, bearings and small parts, it will be a little tight. You should be able to spin it fairly freely in neutral. If not I'd say your endplay wasn't set right or your bushings weren't pressed on all the way.

 

How do I check endplay? I don't think the Novak instructions mentioned anything about that, but I might have missed it, I dont have them in front of me right now.

It does have a few new bushings (One of the new ones from Novak was a few hundreths of an inch too long, so I used one old one). The syncros and whatnot are old, because according to the guy I bought the trans from, it had been rebuilt recently, so I didn't buy new ones. As it turns out it had not been rebuilt, but the syncros didn't look bad. I'm pretty much sure the bushings were pressed on all the way.

I haven't tried spinning it in neutral, mainly due to the fact that it doesn't want to shift because the gears dont want to spin a little to line up I think. It'll be easier to do once I bolt the transmission to the engine so that it's not free to move around as I push on the shifter, so I'll try it that way.

 

You should be able to spin it by hand in all the gears by grabbing the input shaft. If not I'd say there was something wrong. I would pull it back apart before trying to heave it back in.
You check the endplay by putting a dial indicator on the end of the mainshaft (sticking out the back) and read how many thousandths it moves when you try to move it laterally (front to back) in the case. If this isn't set to .002 +/- you are going to have problems. It sounds like yours is set too tight. If you install it like this it's going to burn up right away.

 

Ok, thanks for the help. I'll put a dial indicator on it tomorrow, but I'm going to guess that there is no endplay movement at all. Possibly the adapter kit came with different shims, I'll go through it all again.

Hopefully the mainshaft endbearings will go back in without a press, I'm not looking forward to carrying the transmission up a flight of stairs again.

 

You might also want to make sure that one of the needle bearings where the mainshaft inserts into the input shaft, didn't fall down causing a bind when trying to fully insert the mainshaft. Kinda like the little needle bearing in a u joint cup keeping the cup from going on completely. Ask me how I know
Another issue I found when doing mine was with the adapter bolted up to the trans, one of the bolts protruded through the adapter, enough to rub on the cluster gear shaft.

 

DONT FORGET to put silicone on the bolt threads when you install the adapter plate. The holes go through the back of the trans and will leak unless you do.