833 trans rebuild quick question

Posted By: 68Bullet

833 trans rebuild quick question - 04/19/14 08:52 AM

I am rebuilding my 833 with a basic rebuild kit and a new set of blocking rings. Overall the trans looks good so I am re-using my gears and input shaft. All is going well until I just installed the assembled mainshaft, input shaft and countershaft in the case and installed the front bearing. Before going further I shifted it into all gears and spun the input shaft several rotations in each gear. What I noticed is that in some gears, it seemed to spin fine in either direction, but felt like it was binding up when I stopped spinning one way and then started spinning the other. Upon further testing, what I found is that if the mainshaft is rotating independently from the input shaft (like in neutral), the trans feels like it's binding when I switch the direction of rotation.

My question is this: since I put a new set of roller needles into the input shaft, do those take a little while to take a "set"? I think that the rollers are having a hard time aligning themselves when transitioning from one rotation direction to the other. I know I put the correct quantity in and I double checked that I installed the retaining ring. I just don't know if it's normal for the new parts to be "tight" or if I may actually have a problem.

Posted By: 340SHORTY

Re: 833 trans rebuild quick question - 04/19/14 09:20 AM

without lube and some torque load the syncros will bind..

Posted By: Steve Bryant

Re: 833 trans rebuild quick question - 04/19/14 02:32 PM

Agree with 340SHORTY . I rebuilt my 833 and noticed the same thing. It takes lube and load to break those free and since you have neither right now they still stick rather easily.

A word of advice, take a second and even 3rd look at your synchro rings and replace them unless they look close to perfect. I measured mine and inspected them but I didn't replace them all and now I regret it. My 3rd gear grinds a little nearly every time I shift into it.

Posted By: JohnRR

Re: 833 trans rebuild quick question - 04/19/14 03:07 PM

Quote:

I am rebuilding my 833 with a basic rebuild kit and a new set of blocking rings. Overall the trans looks good so I am re-using my gears and input shaft. All is going well until I just installed the assembled mainshaft, input shaft and countershaft in the case and installed the front bearing. Before going further I shifted it into all gears and spun the input shaft several rotations in each gear. What I noticed is that in some gears, it seemed to spin fine in either direction, but felt like it was binding up when I stopped spinning one way and then started spinning the other. Upon further testing, what I found is that if the mainshaft is rotating independently from the input shaft (like in neutral), the trans feels like it's binding when I switch the direction of rotation.

My question is this: since I put a new set of roller needles into the input shaft, do those take a little while to take a "set"? I think that the rollers are having a hard time aligning themselves when transitioning from one rotation direction to the other. I know I put the correct quantity in and I double checked that I installed the retaining ring. I just don't know if it's normal for the new parts to be "tight" or if I may actually have a problem.

Well here's the first thing I notice ... spinning it in one direction then the opposite ??? huh ???

You do realize the trans only ever spins in one direction because the engine only spins in one direction when it is running .

(unless the engine backfires and then it might go in the opposite direction for a split second at best

) I put that there because I know that some donkey was going to post it ...

The bearings in the input shaft don't need to take a set and you did get them all in correct ? It should be full and the last one will go in with a snap depending on how you load them.

Posted By: VL21

Re: 833 trans rebuild quick question - 04/19/14 04:30 PM

Quote:

(unless the engine backfires and then it might go in the opposite direction for a split second at best ) I put that there because I know that some donkey was going to post it ...

Oh, ye of little faith ... John, would anyone here do that?

I can't even conjure up anyone who would do that!

Posted By: 68Bullet

Re: 833 trans rebuild quick question - 04/19/14 07:01 PM

Yes, the input shaft only ever spins in one direction. But the output shaft could spin in two directions depending on if car is in forward gears or revers. Thus the input and output shafts could "reverse direction" of rotation. Either way, it is just an excersize to make sure everything rotates freely. And I agree that with no lube and that fact it's all assembled with heavy grease probably is causing the "binding". And yes I did replace the synchro rings

Posted By: Cab_Burge

Re: 833 trans rebuild quick question - 04/19/14 07:04 PM

Did you use gear oil or chassis grease to assemble the parts? If so that may be contributing your results

Posted By: 68Bullet

Re: 833 trans rebuild quick question - 04/19/14 07:35 PM

I used high temp wheel bearing grease, but in minimal quantities (just enough to hold all the rollers in place and put a light coating on all friction surfaces)

Posted By: Cab_Burge

Re: 833 trans rebuild quick question - 04/20/14 03:46 AM

I have used both ATF and 75W90WT gear oil in street and race NP833, they shifted easier, a lot easier, with ATF

Good luck, let us know what you do