I am about to rebuild a MkI S 3 synchro 'box.
It ran very well when last on the road, although the 2nd hand lay gear was noisy in 1st.
I am cleaning, replacing bearings, a new lay gear, new synchro rings;
Question: Is there anything that should be done to the gears - like regrinding the faces on the dog teeth (which are not bad) before replacing them?
Thanks in advance.
Bill

I reckon you have everything covered. The layshaft in the 3 synchro should be replaced as a matter of course, not as robust as the later boxes. Make sure you use a good quality shaft. Also replace the 1st motion shaft bearing even it looks ok as these take a heavy load.

Good to see u r doing up one of the boxes which are a joy to use IMO. No synchro on first, but who cares, the ratios are sweet as.

_________________
1967 Cooper S - new front bearings to do.
1965 Cooper S shell - Slow progress. No time or money!
1966 Deluxe- next rustoration!
Mk 2 & XJ6 Jags. Less said the better.

Dont forget to fit the 1st/2nd slider-ring & Hub together "lined up properly" for the little Pall & ramps
it does the work for the 2nd gear syncro to work properly
if you don`t have that 1st/2nd slider hub assy assembled the right way (&/or) forget to fit the pall
then you`ll have a crunching 2nd gear,,, no matter how new the gear or the syncro ring is

have fun
Matt

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No offence intended here but--> anyone writing a book about minis 30 years ago may not have experienced such worn or stuffed-with components as we are finding these days.

You should put your heart & soul into everything you do.

Wondering if Bill B will be using a N.O.S. laygear or an aftermarket item? I have been collecting 3 speed synchro gearbox parts for a couple of decades,some of the contributors to overseas mini forums refer to the readily available non genuine laygears as being made from either "playdough" or "chocolate". Has anyone had any long term reliability problems with these gears?

See attached images Thank you.

Thanks, AEG163job; it was an easy box to use even without 1st.
And thanks Matt for the warning - I try to be careful getting the hubs around the right way. And I'm using your layshaft in the rebuild.
For mjollnir: The lay gear in the box at present was second hand when I reconditioned the box in the early '80s. The dealer told me it would grumble in 1st but the bearing faces were better than my original. He was telling the truth. It has otherwise worked well. I bought a new 22G1100 cluster gear from UK when they became available in '80s. It came in a blue/white box but without Leyland name or logo, so not genuine but I hope it is OK. The part number stamping is not like either examples you have posted.
Bill