I replaced my clutch with an exedy when I got the car, new throwout bearing/pilot bearing as well, was very careful on aligning the tranny with the motor, was fine for a couple hundred miles AGAIN (this will be the 3rd time the trans is coming out) and the damn thing is refusing to go into gear again! (say 75% of the time)

now when i press the clutch in i get a grumble, is that TOB or pilot bearing again?

 

Could be either. When you pull the trans this time, verify that the input shaft isn't bent.

 

Last time I checked it for play and spun it by hand, wouldn't I notice it?

 

bump

 

u need to take the transmission off. cant diagnose. i would guess clutch fork or throw out bearing is going bad and causing problems.

 

i'm going to take it apart again, but what i'm saying is, this happened the first time, now again and i did inspect the clutch fork and tob was new so wtf?

 

Could be your clutch line was not properly bled. Try pumping the clutch a couple times and see what happens. Just a thought.

 

My guess is that your pilot bearing is busted again. If so, you need to find the cause... maybe a bent input shaft or bad input shaft bearing?

 

yeah i'm going to check out the shaft, i inspected it last time i pulled it and it wasn't sloppy so what do i do, use a dial indicator and make sure it's not warped/bent/untrue?

 

Yes... Use a dial indicator on the end of the shaft and check runout...

 

definatly the pilot bearing.....if theres a noise with out the clutch being depressed and quites when pressed thats the throughout bearing.

 

This sounds like a good guess. There's not a lot of support on the input shaft inside the trans. If your input shaft bearing is worn then it will ask more of the pilot bearing to support the shaft and could prematurely wear. When you push the clutch in with the car stopped, the flywheel is turning but the input shaft isn't.. so here's where you hear pilot bearing noise.

You'll hear the input shaft bearing when the car's idling in neutral with your foot off of the clutch. The input shaft is supported by the clutch on the engine side, the main bearing in the center, and the input shaft bearing is left to rotate inside the output shaft, which is stopped.

Here's my input shaft bearing from yesterday's teardown. Mucho ugliness.

 

how difficult is it to get the input shaft bearing out?

 

It's the most burried bearing in the transmission. The whole thing needs to come apart.

 

how did you determine your input shaft bearing was bad?

 

I can't wait to take mine out, i can hear it grinding in there. Just need to find a shop to do it all or find a place to get the parts to do it myself.

 

I wasn't certain that it was this bearing but I suspected it was on the input shaft. I knew that something in there wasn't right though, so apart it came. Particularly when the car was cold, idling in the driveway it would grumble loudly. Push the clutch in and it went away. You could also feel the roughness as you put pressure on the gearshift and slowly shifted gears.

 

hmm mine sounds/feels fine even with the pilot bearing shot, but when i push in the clutch the noise begins and leading up to the noise it's tough to get into gear (Which always occurs 300-400 miles after replacement)

few bad pilot bearings maybe?

 

Wow, that is one badly spalled bearing. Were the input and mainshaft faces reusable?

Dave

 

For parts, Malloy Mazda or www.gttransmissions.com. GT has a bearing/seal/synchro kit, and Malloy of course has everything.

If I were to do it again, I'd buy a known good tranny (JDM with the short 5th) and swap them. Then rebuild the original and have plenty of time to do it. The longer you hear it making noise, the more likely the damage will spread from the $15 bearing to the $400 shafts.

Dave

 

You can barely tell there were problems by looking at the races and I think that's because they haven't been cleaned thoroughly yet. The inner race (outside of the output shaft) was totally clean and the outer race (interior of the input shaft) was a little dirty but I think it might just be bearing material that needs to be cleaned off. I couldn't find specs for mic'ing them out but they look decent enough. I don't intend on replacing them.

 

I wouldn't replace them either.

I think there is a spec on tolerance, but I'm not clear on how to measure it. Item 3 on page J-29 has me thinking this is such a spec, but they don't mention the bearing rollers that are in between each gear and shaft. So would I also mic the rollers and take the total clearance to be a max of .006? (I really don't know!) In any case, unless that gear has symptoms I guess it's not worth worrying about at all.

Dave

 

Yeah, I saw that. I think what they're telling you here is to measure the shaft, and the mating surface of the inside bearing race.. thise should be within that tolerance.. In this case, the shaft and the race are the same piece.. I'll just polish things up, pack this guy will some moly grease and believe that it's all good.

By the way.. thanks for the pics from your project. It made prep much easier. If I can suggest one more thing to people attempting this it would be to get long zip ties and when you take off gear stacks, zip tie them together how they came off. This way you have bigger chunks of gears that you can easily see where they go.. instead of a jig-saw puzzle of parts.

Everything looks like a transmission from the inside with a few weird items.. like the 2 piece synchros. I'm still not 100% certain where those oval-shaped shift rod interlocks live but I'll figure it out.

 

Exedy is sending me a new clutch disc and pilot bearing, i'm going to check for play on the input shaft, he asked me about crankwalk/play in the crank, how do i check for that?

 

Crankwalk is measurable as excessive end play, or axial movement of the crankshaft. You measure it with a dial indicator, or you can use feeler gauges, some all thread and steel bar. Loosen the belts on the front of the engine. Mount the indicator base on the block, locate the indicator on the flywheel. Stick a screwdriver behind the flywheel and gently pry the flywheel away from the block until it stops. Zero your dial on this number. Now push the flywheel in to the block until it stops. Look at the dial. This is your end play. Typical end play is probably in the neighborhood of .005". Crankwalk, or excessive end play is usually a result of dropping the clutch. It beats the thrust surfaces of your bearigs.