7 replies to this topic

[HazleNut21]

Hello all,

 

I am looking for some technical advice regarding gearboxes, bearings, and gear sets. I am undertaking a rebuild of an A+ gearbox for the restoration I am doing on my mini. I have stripped the box and found that one of the gears on the lay gear is a bit worse for wear and I should probably invest in a new lay gear... only to find the 30/26/21/15 set that my gearbox uses is very difficult to find.

 

I am wondering if there is any other lay gear that fits the box that's more readily available, I have seen A+ gear sets that are 31/27/21/15 but am unsure if this is suitable. I have also seen there are conversions to the CR sets but don't know what I would need to complete the task, ideally, I just want to invest in a new lay gear as I already have a rebuild kit on its way. Any advice would be much appreciated. Just in case anyone needs to know, the engine is a 998.

 

Also, I found this (see images attached) bearing on the first motion shaft, I don't know what its called or where to buy one, I haven't found anything that looks the same online, if anyone knows what it is that would be good to know too :) thank you.

 

 

 

 

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[GraemeC]

It is this bearing:

http://www.guess-wor...play.htm?id=151

the outer race is installed in the drop gear casing - they should always be kept as 'matched pairs'. Don't be tempted to just change the inner section.  The outer race can be difficult to replace.

 

What is wrong with your laygear?

Guessworks may be able to supply you with a new, or good condition used one.  Part number is DAM4931.  

Edited by GraemeC, 06 April 2021 - 01:00 PM.

[HazleNut21]

It is this bearing:

http://www.guess-wor...play.htm?id=151

the outer race is installed in the drop gear casing - they should always be kept as 'matched pairs'. Don't be tempted to just change the inner section.  The outer race can be difficult to replace.

 

What is wrong with your laygear?

Guessworks may be able to supply you with a new, or good condition used one.  Part number is DAM4931.  

 

Cheers for identifying that :) appreciated!

 

From what I can see the gear has a lot of pitting on the largest of the gears, and it also looks like something has work away at the edge of the teeth on the gear, just not too confident putting this back in, just in case the damage leads to premature failure.

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[GraemeC]

I'd agree - that doesn't look too healthy!

[MiniMadRacer]

The groove on the top of the teeth is meant to be there by the way.. it indicates a later A + gearbox

[johnR]

I'm guessing some pitting is not a major problem but I'd check with an expert before using it. 

[cal844]

Looks OK to my untrained eye

[Spider]

The Gearset (and Laygear as part of that) is often referred to as a 'Single Line' Gearset.

 

These are somewhat common.
 

Here's one for very fair money;-

 

https://www.ebay.co....C-/123936241574