I just put my AX-15 back together and all appeared good. Followed the book, no parts missing or extra, pics together match pics before etc. Anyhow, it turns in 4th and neutral but in any other gear it is stuck like it is in 4th + whatever gear. I took pics before I put the case on and it sure appears that the 3-4 selector is in neutral but it is not behaving that way. Any ideas?
I pulled it apart before the RTV dried and the 4th synchro was jammed on. I pried it off with a screwdriver and now it works fine. Put it together with no RTV and it works fine. I made sure all of the synchros engaged the keys properly. Something apparently jammed it on. The thing that really concerns me is the reason I am rebuilding this transmission is the 3-4 keys were broken. This seems like just the sort of problem that would break the keys. Is there something wrong with the pilot shaft or is this just a coincidence?
I've had 4th gear syncros get jammed onto the input shaft before myself. It hasn't happened to me since I started loading the syncros grease while installing them.
As for the original condition regarding the broken 3-4 keys, I've never seen that before. Were they all broken? Was the hub shift sleeve on correctly, chamfered edge to the front?
Is the pilot bearing present/correct?
Yes, all 3 were broken and both 3 and 4 synchros toast. Also front and rear sealed bearings had bubbled plastic other than that no damage that I saw. It appeared to be the factory build. I cannot comment on the pilot bearing, I bought if from a guy on CL already out. The synchros were all completely worn out so that they were bottoming out on the ramp.
I was shifting it with the case off and got 3rd synchro jammed the same way. That is a bit concerning. I hope once it is bathed in oil it does not have that problem. It is all together now. Goes through all the gears and N but 5th is a bit of a pain to go in.