5sp counterhold nut clearance?

[Kyle]

Hi all-

I have a ZX five speed in my '72. I rebuilt it about 1,500 miles ago, and have been having trouble with the counterhold nut - the nut behind the 5/R gearset.

<a href="http://www.sonic.net/~kyle/znewloosenutbehindthewheel.jpg" target="top">Picture of the loose nut behind the wheel</a>

Can anyone tell me what the clearance is supposed to be? The first time, the nut came loose, the second time, it was too tight, the third time it was too loose, and the fourth time (currently) I think it's a bit too tight. I set the clearance between the nut and the 5/R thrust washer to .015.

I think it's still to tight, as once in a while it will not want to shift into gear, and you can hear/feel the load through the trans as fifth gear is binding.

Many thanks!

[Marty Rogan]

Hi Kyle,

Sorry I can't help you on the clearance issue.

But, I thought you were the loose nut behind the wheel!!!

Sorry, I just couldn't resist.

Marty

PS: Don't see you over on the boards much.

[Kyle]

Hey Marty-

Thanks for the reply! I think there may be an issue with my email through addler.net domain; the domain is live, but Mike said he can't send to me; I posted the question to the list, and got no replies... so I thought I'd try here.

I keep up with a BB for the 240 volvos, so I've kinda come around to the BB way of thinking. Plus, I get to show off my funky-fresh ride with every post. What could be better!! :laugh:

[Marty Rogan]

That is a cool part of this. I never could figure out how to make the Avatar thing work though.

There are a lot of very knowlegable guys that hang out here and not on the mail list, so I have been doing both.

Usually one or both come with a solution.

Welcome aboard!

Marty

[2ManyZs]

I'm not sure what you mean by setting the clearance Kyle. According to all the info in my manuals, the rear mainshaft nut is to be torqued to 101-123ft/lbs but says nothing about setting any clearance. ?

Thought I should add the torques spec for the counter gear lock nut is 72-94ft/lbs.

[Kyle]

Hehehehe... that probably works on initial reassembly; the multi-decker gear and bearing sandwich (mmmmm.... sandwich) compacts slightly with use, giving some clearance. I can speak from experience that it's definitely possible to overtighten it on "adjustment" - even finger-snug is too tight.

Is the manual you refer to for the four speed or five speed? I could see the four speed not mattering; there's no fifth gear to bind up.

All that said, your post makes me more confident that it's probably set okay. Hopefully the binding will go away with a few miles.

Thanks for the help!

[2ManyZs]

The manual I'm referring to is for the 5 speed... I had a friend of mine copy the pages from a dealers manual years ago when I bought a 5 speed "in a box".... and have never gotten around to trying to put the "puzzle" back together....

I've got an old Haynes manual that has a lot of good photos and description on how to assemble the FS5C71A trans.

One thing they specify in the manual is that there are different thicknesses of the circlip that hold the rear bearing which would affect the bearing spacer and the clearance issue you are referring to..... wonder if that is the case with the later 5 speed as well....

[Zedrally]

Kyle,

I 've got a feeling that this nut is meant to be staked once torqued up.

I had a problem with my g/box in the late 70's with a similar problem, turned out that the stake had either worked loose or was never fitted!

Cost me a new gearbox......bugger.....

[gramercyjam]

The picture even appears to show the indentation where the nut was staked.

[Kyle]

The first time the stake was more of a dimple than a "Hu-waugh!" indentation. Didn't make that mistake the second time. Or the third or the fourth...

K

[2ManyZs]

Err, you mean you aren't using a new locknut every time? That's one of the things the manual is pretty specific about....or should say, that's one thing the manual is pretty clear about, for a change.......

I kinda like the way the early 240 5 speed is set up, they use a double nut, don't have to worry about staking it and having it come loose.....

[Kyle]

The double nut is pretty cool. Had that on the Roadster five speed as well.

As far as using a new nut, dunno, I don't have a manual :classic: but putting a new nut on there would require pulling off the rear mainshaft bearing, and that sucka was ZERO fun to put on. Taking it off and on and off and on would likely be its death.

I'll just keep beating the stuffing out of it and see what happens... not like it's that hard to take the trans out again. Getting pretty good at it!