Lay gear end float
Turbo Mini Forums

Been replacing the bearings and thrusts for the lay gear in the van's new box.

With a brand new big thrust and a new DAM1381 (+ .124 - .126) small thrust washer I have 0.010 of end float. The book says .004 - 0.007.

To get it down to spec I need a DAM1382 (= .127 - .129) and they are NLA. I have the original one, but it has a load of wear from the shitty old bearings that had been used previously.

Will it be OK with 0.010" or do I need to go hunting for rocking horse poo?

Edited by apbellamy on 7th May, 2011.

I'll stick my neck out and say it will be OK assuming that you are using straight cut gears.

Not as critical as with helical gears as the side loads go away.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Thanks Paul. Yes, it's a straight cut gear set.

These are the bearings that came out of the box, the one on the left is the original DAM1382. Only fit for the bin IMO.

they dont look that bad to me, I'd use them on a SC box on the basis there will be no loading on them.

Use some 0.005" shim steel behind the larger thrust. Works a treat when in need.

The 0.130 - 0.134" thrust is available though and I might have one of those too

Edited by Sprocket on 7th May, 2011.

Andy.

I have some 0.006 in shim material if you want me to cut you a piece and post it. It's from a roll of the stuff called 'Shim in a Can'. Bloody fab. You can cut it with a pair of sharp scissors.

Let me know if you need some.

Richard.

Minivanless, but reluctantly happy living with the decision. There'll be another one day.
http://www.youtube.com/profile?user=minimadmotorman#p/u

Edited by apbellamy on 7th May, 2011.

The bearings should be enough of a nip in the laygear that the thrusts should only act on the gear endfloat, not the bearing. If in doubt drop a dab of retainer on the bearing outer cage when fitting.

Thanks Tom. New bearings aren't the snuggest fit so will do that.

I'd say 0.010 endfloat is OK with a straight cut box.

that is still 6 thou slop, and a high frequency movement of 6 thou will generate vibration. Vibration saps power and kills bearings quicker.

For the simple task of getting the end float correct, is it worth not doing it?

I don't care for the 'straight cut is ok' argument, that has fuck all to do with anything

that is still 6 thou slop, and a high frequency movement of 6 thou will generate vibration. Vibration saps power and kills bearings quicker.

For the simple task of getting the end float correct, is it worth not doing it?

I don't care for the 'straight cut is ok' argument, that has fuck all to do with anything

So good he said it twice LOL!!

Richard has posted us some 0.006" shim steel so I'll slip some of that in behind one of the thrusts ( glued to the tang) and have a cock on 0.004" end float. perfec

Have you got the thrust we need then Colin?

If something is worth doing, it's worth doing half of.