[Adzer]

Rebuild gearbox/replace worn synchro's?

It's a 5 speed manual box and 4th synchro is shot.

I'm a competent mechanic and have done engine rebuilds and engine conversions etc but have never entertained gearbox internals.

Would it just be a case of splitting the box, pulling out the gear set, splitting the gears etc off the shaft, replace worn parts then rebuild in reverse order or do you need to check clearances/tolerances and use shims?

I've spent a fortune on the car over the last 2 weeks so reluctant to pay someone to do the job I could prob do myself

Any advice appreciated

 

[Marck]

I've dealt with a few gearbox rebuilds, if you feel confident with engine rebuilds etc you will probably be ok

you will have to try do some research for the specific box about tolerances etc. I've never rebuilt a evo box so not sure what the case is for them. some gearboxes need measurements etc taken where others don't


Mark

 

[Longbow77]

There is nothing particularly complex about it, and all of the reference information is available on line e.g. http://evoscan.com/manuals/Evo9/GR00000500-22B.pdf

You'll need access to a hydraulic press to get some of the gears and bearings on/off the shaft. It's one of those jobs that you only want to do once (as getting the box in/out is a bit of a PITA) so check every component thoroughly and take your time. Aside from replacing worn components, things to take particular attention to are the selection of the half-moon thrust washers on the end of the input shaft (need to get the clearance as close to zero as possible - and replace the spring retainer clip too) and getting the specs of 3 x shims that fit between the bearing races and the outer case right. I assembled and disassembled the box 3 times to ensure the readings were accurate (I used the crush solder method). All parts are available though Mitsubishi