cpark_12 Posted March 16, 2013 Share Posted March 16, 2013 I had a problem with my transmission the other day. It just lost 1st gear for a bit. I let it sit for an hour or so, then it shifted through all the gears just fine. The next day, 1st was gone again and the synchronizers seemed to be going bad. It kinda grinded going into 3rd. Finally, I was driving and shifted into 3rd and it just locked the rear wheels up. I took that tranny out and put in a 4 speed from a 76 280 and all was good...for a day! The exact same thing happened again. I completely lost 1st gear. Are these trannys known for this? Anyone else ever have this problem? I'm gonna start tearing into the 5 speed next week, just wanted to check here to see what's going on. Oh...83 280zx. Original 5 speed, n42 head, 4 barrel carb. Quote Link to comment Share on other sites More sharing options...
cpark_12 Posted March 18, 2013 Author Share Posted March 18, 2013 No one? Quote Link to comment Share on other sites More sharing options...
NewZed Posted March 18, 2013 Share Posted March 18, 2013 (edited) Your story is kind of confusing. You said that with the first transmission you "lost" first, then were driving, then locked up the wheels in third. On the second, you lost first, but didn't really say if third locked up again, although you did say it failed exactly the same way. Not really clear what "lost" means either, does the lever go to the place where first should be engaged and there's nothing? Or does it not go to the spot for first as at all? How did you get the car home if the rear wheels were locked up? Did they unlock and you just used second, fouth and fifth to drive it? By now, it seems like you would have at least drained the fluid from the first transmission and seen some broken pieces that would tell you something. The transmssions aren't known for this. They usually just make bearing noise and start grinding when shifting. One thought is that you don't have a pilot bushing in the end of your crankshaft and you're overloading and destroying the bearing in the adapter plate. That would be common to both transmissions. I've not had it happen, but it seems possible. Edited March 18, 2013 by NewZed Quote Link to comment Share on other sites More sharing options...
EuroDat Posted March 18, 2013 Share Posted March 18, 2013 The first tranny sounds like you had a shifter problem. Has anyone fiddled with the detents. Thats the little springs with the ball bearing in the side. It could also be the locking pin that locks the selector fork to the selector shaft. The reason I think this could be the problem is because you grinded it into 3rd and you locked the rear wheels. That grinding was the transmission telling you its still in another gear. Once it engaged it locked the rear wheels. I would check out the selector mechanics for problems. I have never had this problem on one of these transmissions. They are generally known to be reliable for there day with the exception of the FS5W71B with the fibre 5th gear synchro. Quote Link to comment Share on other sites More sharing options...
cpark_12 Posted March 19, 2013 Author Share Posted March 19, 2013 (edited) On the first transmission, 1st gear would kinda come and go so to speak. It would slide into place, but it didn't have the "catch" feeling like normal. And when I let off the clutch, it would act like it never went into gear at all, just stayed in neutral. Then it would go into gear and shift just fine. I drove it for about 2 days like that, then it just locked up going into 3rd. I played around a little and got it into 2nd and limped to a parking lot where I left it and towed it to our shop. The transmission in it now is starting to do the same thing. 1st, 2nd, 3rd, and 4th are going in and out, reverse is just fine. I actually drove in reverse to the shop (about a mile) from where it started acting up. I haven't driven it since Now, I did get the original transmission taken apart today and it's very bad! Most of the gears are gone, like missing teeth gone. I'll get pics up soon Edited March 19, 2013 by cpark_12 Quote Link to comment Share on other sites More sharing options...
NewZed Posted March 19, 2013 Share Posted March 19, 2013 Pilot bushing? Quote Link to comment Share on other sites More sharing options...
cpark_12 Posted March 19, 2013 Author Share Posted March 19, 2013 Quote Link to comment Share on other sites More sharing options...
cpark_12 Posted March 19, 2013 Author Share Posted March 19, 2013 Quote Link to comment Share on other sites More sharing options...
cpark_12 Posted March 19, 2013 Author Share Posted March 19, 2013 I haven't torn into the 2nd transmission yet, but hopefully I'll get it out and apart tomorrow evening. Quote Link to comment Share on other sites More sharing options...
NewZed Posted March 19, 2013 Share Posted March 19, 2013 Check the bearings in the steel plate (adapter plate). You might find that a few balls are missing. Just a guess. The pilot bushing fits in to the end of the crankshaft, at the center of the flywheel. The nose of the transmission main drive gear (shaft with a gear on it) is supported by it. Maybe you're just ignoring me, but I'm curious. Quote Link to comment Share on other sites More sharing options...
EuroDat Posted March 19, 2013 Share Posted March 19, 2013 I would like to see photos of the selector fork roll pins. Its just a hunch, but I think that could also be a likly source of the problem. If a pin sheers through, the fork can slide back and forward on the selector shaft. The detents on the selector fork will work normally giving that click feel but wont prevent interlocking which is what you discribe (locking rear wheels) and the photos show the result. Quote Link to comment Share on other sites More sharing options...
cpark_12 Posted March 19, 2013 Author Share Posted March 19, 2013 The roll pin in the shift fork is fine, but the fork did crack around the pin, so that may have been the problem. And I'm not ignoring you newzed, I'll cheek it out when I get to the shop today. Quote Link to comment Share on other sites More sharing options...
cpark_12 Posted March 19, 2013 Author Share Posted March 19, 2013 Okay, all the bearings look to be fine (all the balls are there) and the pilot bushing is good too in the first transmission. I'm gonna try to get the other transmission out tonight and hopefully apart, but that may be tomorrow, we'll see there's the shift fork that broke around the roll pin. Quote Link to comment Share on other sites More sharing options...
EuroDat Posted March 19, 2013 Share Posted March 19, 2013 Cant be certain but I think the roll pin break out caused your problem. That way the selector fork could slide up and down the selector shaft. The detents lock the shaft, but the fork is this in first gear. All your symptoms point to this kind of problem. It will be interesting to see what is inside the 4sp. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.