Hi all, I have a Massey 3080 16 speed with Dynashift trans that is not engaging the low range reverse. Forward is fine but reverse will not engage and hold in. I have the Dynashift cover off and there are no obviously worn parts that I can see. There is a hydraulic component in the cover that I have not investigated yet - apparently it is fed from the low pressure hydraulic circuit. Any help much appreciated. Bill
Massey 3080 Dynashift woes
- Thread starter Muganic
- Start date
diesel power
Well-Known Member
Can you post up a picture of what you taken off?. I'm struggling to picture what could be wrong that only low in reverse is affected.
gone
Well-Known Member
I, like you, think there is a slight mix up here, the 16 spd with splitter was call a speedshift?
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Apologies for creating confusion - you are correct, I do have a Speedshift transmission, I don’t know if this would make it any easier for diagnosing my problem.
mixed fleet
Well-Known Member
So it's a 32 speed, I have 2 of them here.
You won't do much from the side, you'll have to split it . Might only be the famous "big Nut" .
Not that difficult to work on.
You won't do much from the side, you'll have to split it . Might only be the famous "big Nut" .
Not that difficult to work on.
Hi, can you elaborate on the “big Nut“ problem? Where does the tractor need to be split? And any tips much appreciated. I have previously put a clutch in this tractor. Thanks for your input.
mixed fleet
Well-Known Member
Same split as for the clutch, remove speedshift unit ,that exposes the front of the gearbox.
You should see what's gone wrong from there.
There a big Nut 40 - 50 mm on the end of the bottom shaft (Hollow) Keeping the whole assembly together.
It relies on a tab washer, to keep it from loosening.
There well known for failing, even when new.
The 32 speed was a very poor gearbox. Any sort of rough handling and your in trouble. There a one driver machine.
Thanks a lot for your info, I now feel confident to go ahead with the job. An owner of the same model tractor over here in Oz had problems with something wearing in the selector cover and was convinced that would be the issue which is why I removed the side cover. In hindsight I guess it didn’t need to be removed.
scoffcruddle
Well-Known Member
Well split the tractor today and removed the Speedshift and reverse shuttle. Nothing obvious as yet the “big Nut” doesn’t appear to have moved. The retaining washer is part of the nut and is retained by the punch indentation into the keyway. The nut will move back and forward a little but only within the constraints of the keyway. No movement back or forth of the gear on the shaft. The adjusting screws in the selector dog behind the selector cover were tight. Will investigate more tomorrow
.
mixed fleet
Well-Known Member
Your making good progress. I think that I have done that overhaul 3 times.
Twice the repair was just tightening up the big nut and securing it . Yours must be ok .The last time I put a small bit of weld on it with a 29/9 rod.
Another time, I replaced one syncro hub, possibly the forward/reverse one.
It's a good few years ago but I remember you could see the wear on the sloped friction surfaces.
A follow up to this thread, after not finding obvious mechanical problems I looked more closely at the A-B shifting mechanism in the selector cover and replaced 4 O rings therein as I could detect some wear on them. Glad I had a workshop manual for setting up the A-B piston travel and refitting the selector cover, anyone doing this I would strongly recommend getting a workshop manual. Had to make up a bolt to lock the A-B shaft for refitting the cover- a 19mm x 1.5 pitch thread - an odd size. All seems to be OK now. Since bought a JD6610SE with 4500hrs in excellent order which took the urgency off fixing the Massey. Thanks for all contributions and help.
Cheers
Bill
Cheers
Bill