Have a p200e and am doing gearbox job. Couple of questions, when the gears are fitted to shaft, should the slots for cruciform all be aligned, or is there no difference? Next question, are the gears and shaft interchangeable with after 83 PX (except cruciform, later one is flat) I can get complete overhaul kit for PX and 4th gear has a thicker mid section. Current gear is PX type, and all works ok. Kit has new axle, gears, pin, cross, clips etc. Pin on PX (I think) needs larger spanner to tighten. P200 has 13mm, but don't know about the length re selector box. Anybody with appropriate experience help out please?
Hi Paul. I have a P200E and have reassembled the gearbox a number of times. As you know, the individual gears have to go back the same way they came out. If one is swapped around it will not properly line up with the layshaft gears. You don't need to line up the slots on the individual gears on reassembly. The cruciform will work it's way down the shaft in steps as you spin the gears. You should also check the end float of your gear set on the shaft between the gear spacer and the circlip. End float should be between 0.15 - 0.4mm. My set was worn so I had to go up in spacer size. PE spacers have one tab but PX spacers with 4 tabs will also fit a PE. Yes, post 1983 Lusso models of the PX have an improvement in the gearbox design which makes it less likely that gears will jump out. As well as the notches in the 'bat-wing' gear selector cam, the cruciform itself better locks into each gear. However with properly adjusted cables, I have no trouble with gear changes. Can I ask you why to want to fit a later PX gear set? As well as a new output shaft, gears and cruciform you also need a new gear selector box as the throw is different and longer studs to mount the selector box onto the engine case. I'm not sure whether the new style gears will mesh with the layshaft set which has a smaller diameter shaft, 11.5mm compared to 13mm for the later PX gearbox. These links might help. David
Hi David. Thank you for the info. The links were very helpful. Not planning to change gearbox, but have recently had apart to re-shim gear stack. When I put it together last time, the clearance was at the extreme limit so all seemed a bit loose. Was running ok, but there was obvious slack in gears. This time got new shims and reassembled with only just the minimum clearance, and was having difficulty getting 4th cleanly. Seemed to be 2 "clicks", half way each and was not right. On the gear the "mid section" according to the pic attached should be approx 5mm, but the existing gear is more like 6.5 with the inner surface being totally flat. This kind of makes sense as it runs against the collar. I'm thinking that with the minimum clearance, the gear may be binding a bit against the collar, not allowing proper gear shift. The PX gears I think are in fact flat inside (like this one). Still thinking about best option, but I think will re-assemble with a bit more clearance in the stack. Have attached a pic from GPS 4th gear details. Thanks once again, and if you have ideas would love to hear them. Cheers P