LT77S first gear problem

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Posts
25
Location
north east
Hi All,

I've had the LT77s 56A Suffix H rebuilt twice now by a local gearbox specialist. First time had new mainshaft, 1 through 5 baulk ring triples, 1/2 thrust washers and gaskets and seals.
Then when i finally finished the rebuild and had the defender on the road it kept popping out of first gear and second didn't feel much better. So back to the specialists to see what was wrong, they informed me first gear was worn and needed replacing. Annoyingly gearbox back out and off for the work again, this time new first and second gear, new syncro STC8577 (Got lucky with this part as all of the major suppliers have it on back order and one shop in Ireland happened to have had it in stock since 2012), not sure on the make it wasn't a blue box part but the sticker said OEM part, and then new seals and gaskets.
Box back in and now first gear doesn't pop out but sometimes i have trouble getting it into gear at a stand still, its like pushing a brick wall.
  1. Clutch (new with heavy duty release bearing) seems to fully disengage as the tell tale LT77 rattle goes away and all other gears select fine
  2. New master (LOF upgraded one), slave (orientated bleed nipple at top) with 3mm spacer and rubber pipe
  3. Bled on an incline no spongy feel, doubt there is any air in the system, although travel is at the bottom 3 inches of the pedal
  4. ATF gearbox oil and 0.5L of Lucas heavy duty oil stabliser
  5. All the other gears select fine (1 to 2 and 3 to 2 are fine) and some times it will go into first no problem
  6. If i select 2nd and then get it rolling i can then get it into first
  7. 1.5mm shims on the 1/2 bias, have changed the amount of shims around but made no difference
  8. I can roll the defender along and stop and it will go in 1st, i can then move it a meter or 2 and it won't
Anyone got any idea what might be going on with it?
I might remove the 3mm slave spacer as the clutch engage ment is low to the floor, i originally put it in as with a new britpart master the travel was still very high, but i don't really see any connection to the gearbox problem.
 
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No idea on box prob, but pretty sure mine does not have the spacer.
The spacer (part no. 591988 see page 302 of the parts catalogue) is just to adjust the biting point, the land rover part is 1mm i made my own because with the britpart master the bite point was at the last inch of travel. But since i now have a LOF one and the bite is now at the bottom i'm going to play with the shims, perhaps the clutch isn't fully disengaging because the slave is spaced too far out now.
 
The spacer (part no. 591988 see page 302 of the parts catalogue) is just to adjust the biting point, the land rover part is 1mm i made my own because with the britpart master the bite point was at the last inch of travel. But since i now have a LOF one and the bite is now at the bottom i'm going to play with the shims, perhaps the clutch isn't fully disengaging because the slave is spaced too far out now.
just remove the shims
 
must be they are easily damaged during assembly on h boxes and many parts are poor
Well there seems to be little to no chance of getting a new syncro hub kit so just going to have to hope the parts maybe wear together as i don't think i want the hassel of it being rebuilt for a third time.
Thanks for all your help
 
Well there seems to be little to no chance of getting a new syncro hub kit so just going to have to hope the parts maybe wear together as i don't think i want the hassel of it being rebuilt for a third time.
Thanks for all your help
does it work better engine off,the only wearing in part is ftc4010
 
does it work better engine off,the only wearing in part is ftc4010
No just depends on if i get lucky, gear selection is strange, can move 1m forward and its fine move another meter and it won't go in gear. Might find out what part number they ordered for the first gear and make sure they got it right, as far as i understand its FTC1989. Not sure if any other gear would fit.
 
No just depends on if i get lucky, gear selection is strange, can move 1m forward and its fine move another meter and it won't go in gear. Might find out what part number they ordered for the first gear and make sure they got it right, as far as i understand its FTC1989. Not sure if any other gear would fit.
thats 1st gear i gave baulk ring part number
 
No just depends on if i get lucky, gear selection is strange, can move 1m forward and its fine move another meter and it won't go in gear. Might find out what part number they ordered for the first gear and make sure they got it right, as far as i understand its FTC1989. Not sure if any other gear would fit.
sounds like baulk rings are jammed rather than acting as a brake
 
thats 1st gear i gave baulk ring part number
Sorry wasn't clear, i'm going to find out from the repair shop what part number for the first gear they used to make sure they have installed the right one. As when i talked to them they were under the impression it was a V8 gearbox casing, maybe they ordered a different one.
 
Sorry wasn't clear, i'm going to find out from the repair shop what part number for the first gear they used to make sure they have installed the right one. As when i talked to them they were under the impression it was a V8 gearbox casing, maybe they ordered a different one.
dosent matter if its v8 or 4 cylinder casings are differentiated by suffix though casing and sandwich plate are machined pairs,
if it goes in other gears when stood its not clutch
if it drives ok once in it and goes in sometimes it must be baulk ring mechanism related
h suffix gears are the only ones with no gear cone the other wouldnt fit and wrong tooth count would be noticeable when driven
 
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dosent matter if its v8 or 4 cylinder casings are differentiated by suffix though casing and sandwich plate are machined pairs
if it goes in other gears when stood its not clutch
if it drives ok once in it and goes in sometimes it must be baulk ring mechanism related
Makes sense, well at least i can go back to the rebuilders with an informed idea of what the problem is likely to be.

Thank you for your hell James
 
Makes sense, well at least i can go back to the rebuilders with an informed idea of what the problem is likely to be.

Thank you for your hell James
when they build the main shaft up ie fit 1st/2nd synchro hub ,then the compound baulk ring assembly then thrust washer it has to be carefully aligned with the synchro and first gear so the assembly floats between the hub and gear and held like that whilst rear bearing pressed home then checked by selecting both gears by hand using the synchro hub
 
Whats everyones thoughts on it being a worn selector fork?
Land Rover is going to the gearbox specialist on wednesday and they've offered to take care of it all for me including box in and out, can't fault their after customer service.
 
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