95 240sx transmission issue (synchronizers???)

[maxima278]

If the best solution here is to replace the transmission, then that simple answer will do and you can get on to other people.

Ever since I installed the engine/transmission in my 240SX, It has grinded slightly going from first to second, and from second to third. I could almost always avoid this however, if I shifted slow and took it easy on accelleration. If I ever got on it, it would grind. In general, nothing ever seemed to line up right, but it drove fine. Now, today when I drove it, when I mashed the clutch, there is a grinding noise, its hard or impossible to get into any gear, but I can let it out, mash it again, and it will go into gear. The grinding stops once the clutch is let all the way out and the car is moving. Some times it works fine, but it seems to be getting worse.

Are these transmissions easily (or even possibly) rebuildable at home? Can I easily and cheaply buy parts for it?

Unless I go KA turbo, I'm going to rip the whole mess out and start over with an SR or RB some day(I don't care, I just want a 300-400 hp car in the end) so I'd like to keep it cheap so I can keep it running until then.

Thanks

[NISTECH]

Honestly it sounds like all along its been a clutch issue. It sounds like you clutch rod to the pedal was misadjusted. When correctly adjusted the clevis should float freely on the clevis pin. [ these are the pin and fork that attach your clutch rod to the clutch pedal] It sounds like now you have possible a worn clutch and a worn pilot bushing or t/o bearing.

You most likely have worn bualk rings from the grinding. But I think fixing your clutch issues will resolve 95% of the problems you are experiancing.

[maxima278]

honestly I've fooled around with that adjustment many times trying to solve the grinding problem, but I never knew that it would cause things to wear out. Clutch problems sound cheaper than transmission problems though!

I must bother you with one more question: sometimes my starter hangs up for a second or two after I let go of the key. Just once the other day,(while I was jumping it off from the battery having gone dead) it hung up long term and the starter was trying to turn over even after I pulled the key out. It died out right after I swiped the jumper cables off. I jumped it off again and its been fine ever since. I suspected the starter solenoid but have yet to locate it. Any advice? (honestly I did not search THIS topic so I appologize if I should have)

[NISTECH]

You may have gotten an arching effect when you did that causeing it to hang up. Its always a good practice to let the battery in the car being jumped gain a decent charge before firing it up.

[maxima278]

my clutch still engages well with no slipping. The only problem is getting it in gear and getting it started. I'm hoping it is not worn out. I checked and the clutch pedal is adjusted right, although it has not always been the case. I adjusted this a few months ago because there was too much play in the pedal. I would have thought that whatever damage I did would have stopped right there what about you?

Worst case scenario, is this going to strand me on the side of the road if I continue to drive the car? (it is not needed as a daily driver)

Since this is a temporary drivetrain, and I don't think the clutch itself is harmed too much, how big of a job is it to change out the throw-out bearing, pilot bushing, and those rings you spoke about (I believe there was a type-o and it came out bualk rings, but I don't know)?

[benemorius]

The problem you are having would be the opposite of a slipping clutch. The clutch is not being allowed to fully disengage. A problem with the clutch hydraulics/linkage frequently causes this, though it could still be an internal transmission issue. If readjusting the linkage didn't help, you could have a hydraulic fluid leak or perhaps air in the system.

At any rate, if it is indeed a clutch issue causing your problems, you may well find yourself stranded somewhere unable to get into any gear one day. Meanwhile, the more you force the transmission into gear, the more wear you cause your synchros. As Nistech said, it sounds like a clutch issue and if fixed, the majority of your problems should go away so long as you don't continue to grind or force gears.

PS: If that day comes where you can't get into any gear and you must get the car home, you should be able to force it into first gear, and then match revs to shift once the car is moving. (search 'match revs')

[maxima278]

I had another guy today tell me that it may have something to do with the fluid in my clutch master cylinder not being bled enough. I did not have enough daylight when I got home to test this theory to the fullest, so I simply topped the fluid off (it was a little low) and drove in a way where I was constantly pumping the clutch to build pressure, and I slowed down my shifting. It did not go perfectly, but I had little to no grinding and a whole lot less of the other grinding sound I was getting in first and neutral with the clutch mashed in.

I'm definitely going to look into replacing the master cylinder and slave cylinder with new ones as soon as I can since those things don't matter as far as which engine I swap in when the time comes. I just need this one to get me by until then, thats all I intended it for when I put it in.

benemorius- are you a nissan mechanic for NICO also?

[benemorius]

The fact that pumping the pedal helps reduce grinding supports the idea of hydraulic problems, and the fact that the fluid was low obviously points to that problem being a leak. I wouldn't start throwing money at the problem. Look for signs of leaking fluid first. If you can't find any leaks, try bleeding the line to make sure there isn't any air in it.

No I am not, but I do try to cut down on their workload any time I feel confident that I can help and not just confuse matters.

[NISTECH]

And he does a great job and is appreciated for greatly

[NISTECH]

The bualk rings are the brass rings that align the syncronized hubs with the gear as well as brake the gear to allow for a smoother engaugement. When the clutch isnt reduced fully you will have a harder time getting that to take place and have the grinding.