Gear Box Fault

My gearbox hasnt been great for a wile now a bit awkward to get into 1st gear - the rest are ok. Today I can get it in gear no probs but there is no movement through to the wheels. When you take your foot of the clutch the engine is under labour and will stall so there is power going into the box but not reaching as far as the props. I have jacked up the wheels and they turn freely when out of gear and not when in gear so i am guessing that means the transfer box is ok?

Any thoughts??

how old is it, what mileage etc

The engine and box are out of a late 200tdi that had covered 90k i have done about 5k more.

I took the input shaft/carrier out of the transfer box to se if the main shaft turned and the carrier teeth have big chunks taken out of them. I put the engine in gear - as no longer connected to the transfer and the shaft spins freely and true. maybe the carrier gears were jamming on the associated cogs due to the uneven teeth?

Photo
These are different sides of the carrier pretty much exactly opposite. What could cause such a thing? the cogs in the box all appear in good condition still..

Is there a stud inbetween the transferbox and gearbox that bolts the boxes together? Was there a bolt that went tight before it was home when bolting these together?? If its not a stud and a bolt has been used its possible to put a bolt in that is too long and just mabe cause somthing similar to this although I thought that was lower down in the transferbox TBH. Jai

didn't think that the bolts between gearbox and transfer box were anywhere ,near the input shaft, is there any other damage in the transfer box.

Having now taken the transfer box inspection cover off all of the gears seem absolutely fine. Just the input damaged.
Now the Engine and gearbox i took from a late 200tdi but the transfer box is original from my 1985 90, wonder if there is some connection there..