H all,
Sunday morning at El Mirage we warmed up the engine and drive line in the pits on jack stands and set the timing. All went same as usual so we were set to run. Waited our turn and three cars back from the line we start it up to get it up to 180. Shut it down tighten the belts and go to push it forward. No go, trans is locked up and won't shift. Tony held the clutch in and we towed back to our pit. We took the linkage off to get that out of the equation but the 3 - 4 lever won't move. Today I pulled the trans and put it on the bench. Shifter forks look fine no blue no gouges. 1-2 slider will move, 3-4 won’t. No swarf in the case light synchro dust in the oil. Main shaft will not turn freely turns about 60 degrees and binds, turn it back, same thing. Front bearing retainer off, snap ring off, pull front bearing. Bearing is fine. Tail shaft off, mid plate unbolted, both sliders forward and snake the main shaft assembly out the back. Removed the front input shaft from the assembly, needle bearing race and needle bearings pristine. Remove snap ring to get 3rd gear and 3-4 slider off and the synchro assembly comes out the front as I am sliding it off the rear shaft. I honestly don’t know if it was still together correctly when I started or not. The slider synchro mechanism involves two springs three dogs and two synchro rings. It is very fiddley to get together right and seems to want to disassemble itself at the slightest touch. I checked the rest of the bearings and all roll smoothly with no snags. I re assembled the 3-4 slider and synchros and put the main shaft back together. It turns freely and both sliders work smoothly. I can only think that somehow one of the synchro dogs got free inside the slider and was jamming the mechanism but I can’t tell for sure. I am no transmission expert can anyone out there shed some light on this?