tranny squeal with clutch out

[PAwelder]

so i seem to be hitting a rough patch with my nissan. A little over a month ago i had to replace my trans, so i did and i replaced everything in the clutch area as well, from rear main to the t/o bearing. well two weeks after that she blew a head gasket, which i had done once before, incorrectly i may add, so it wasnt a big deal this time, a few hours searching around ratsun learning how to do it right then two nights after work and shes running like a top. so here is my latest issue and hopefully one of you guys can shed some light on the issue. she started squealing when i first start her up in the morning, but only in neutral with the clutch out. even the slightest tap on the clutch will stop the squealing till you let off pressure. after a little bit it will go away. maybe im paranoid but the last time i ignored noises my counter shaft broke in half. i have looked through a lot of threads and i have a few ideas of what it might be. i put 75w-140 royal purple in my trans, it was the only one i could find at the auto parts stores that was yellow metal safe, is that too heavy of an oil for it and if so what is a good replacement? second is the throw out bearing, i didnt realize you were suppose to grease the bearing itself i just greased the inside and the parts that touched the fork. i dont think this is it because the squeal goes away when you put pressure on the t/o bearing. im kinda stumped at this one. and i will figure out how to post pics on this thread so you guys can see my 720. 

[wayno]

What you saying sounds like a bearing, if you press on the clutch pedal and the noise goes away, well that sounds like the bearing.

That said, do you have about a 1/16th inch play in the clutch arm/slave push rod when you grab onto it underneath the truck?

[datzenmike]

Apparently the release bearing comes sealed with grease in it. If I was the source of that info I may have been going on old info from my '64 Dodge? If the bearing is new it will be fine.

 

If installed properly the release bearing will not be turning when the clutch pedal is all the way up and clutch engaged.

 

The pilot bushing will also not be moving relative to the transmission input shaft because the clutch is locking them together.

 

Only thing left is the transmission input bearing and the counter bearing below it.

 

 

 

Now....

 

75w140... just how thick is that in real terms? If synthetic, does it get thick with the cold like regular gear oil? If the answer is yes then get something down near 90w.

 

You mention pressing on the pedal and the sound goes away. This sure sounds like the release bearing to me, although as stated above it shouldn't be. Only way the release may be rubbing the clutch diaphragm fingers is if the wrong length release bearing collar was used. If the release bearing is constantly rubbing and spinning it will not last long.

 

 

 

That said, do you have about a 1/16th inch play in the clutch arm/slave push rod when you grab onto it underneath the truck?

 

Wayno has a good point here. There has to be a very small amount of play so that all the hydraulic clutch fluid can release and return to the reservoir. Any trapped in the system could hold the release bearing against the diaphragm fingers spinning it.

[wayno]

I see I need to be a little more descriptive, when I said it sounds like a bearing, I meant a transmission bearing, not the throwout bearing.

When you received the used transmission, did you pull the front case off and look at the bearings, or did you just install it?

[PAwelder]

I got underneath her during my break at work and i noticed the t/o bearing fork has no play in it. Is there a way to adjust the tension at the pedal? Or will i have to drop the tranny?

[wayno]

Can you get a photo of the arm straight from the side?

When you installed this transmission, did you use your old throw out bearing collar, or did you use the collar that came with the new transmission?

When you open your door and bend down and play with the clutch pedal, is there any movement in the rod that goes to the clutch slave?

If everything else is correct, which it would be strange for it to change, unless something else changed, get a adjustable crescent wrench, and compress the clutch arm and remove the rod you have from between the clutch arm and clutch slave, now find a bolt the same size, cut the head off it and at the same time make it slightly shorter, say maybe an eight inch shorter, use your crescent wrench to install the new shorter rod, make the rod shorter until you have a little play, each time you install a new rod, get in the truck and step on the clutch a few times, you want just a little play in the rod(1/16th inch).

It would be helpful to see the way the arm sticks out of the side of the transmission now, that way I might be able to figure out if the collar is the correct one for that transmission/clutch combo.

I got underneath her during my break at work and i noticed the t/o bearing fork has no play in it. Is there a way to adjust the tension at the pedal? Or will i have to drop the tranny?

[datzenmike]

I got underneath her during my break at work and i noticed the t/o bearing fork has no play in it. Is there a way to adjust the tension at the pedal? Or will i have to drop the tranny?

 

First check the pedal play. You should be able to depress the pedal about 1/16" or a few mm with your thumb before feeling strong resistance. The pedal to master pushrod under the dash is adjustable. If the master can't return fully, then hydraulic pressure may be trapped in the line holding the clutch arm and bearing against the PP.

[PAwelder]

ok, so i checked the play on the pedal and it is at least a 1/16th if not 1/8. when i did the trans i used the new t/o bearing sleeve that came with the clutch kit, now the clutch kit is a 4x4 clutch kit and the trans is a 2wd trans. not sure if that would make a difference. so literally 10 minutes ago i was bleeding my slave cylinder because when i was pushing on it during lunch today it some how got air into it. while i was bleeding it noticed there is no stop on the slave piston if let go it will creep its way all the way out of the cylinder till fluid comes out. i think it is a cheaper after market part so im not sure if it is supposed to be like that. Here are the requested photoshad to include a picture of the old girl 

[wayno]

What counts when checking the clutch pedal play is that the rod going threw the firewall that connects to the pedal be loose when the pedal is not being pressed on.

The arm coming out of the transmission looks to be about right, but you say the rod between the slave and the arm is not slightly loose, that is bad, you need to shorten that rod or make one out of a bolt that is slightly shorter, it needs to be short enough for the rod to have a 1/16th inch play.

You say the slave is leaking?

[PAwelder]

i double checked the shaft through the fire wall and its loose when the pedal is fully out. as for the slave it doesnt leak fluid, but say you were under the truck and you pushed it back in a little, it would slowly creep its way back out until it hit the arm again and then stop once it was resting on the arm it almost seems like its got the weight of the fluid on top of it and thats what is applying the pressure.

 

and as for your question a few posts back wayno i never did pull the front cover off the trans, which i am now kicking myself for. once everything is checked and correct with the clutch, if the noise is still there i will be dropping the trans promptly with new bearings in hand 

[wayno]

You could try something to see if it changes anything, you will need to find a strong spring the appropriate size, what you could try is to connect the spring to the arm, and then connect it up to a place in front of it like on the frame, and then see if the noise goes away, it kinda sounds like the arm is touching the fingers of the clutch cover, and that will likely cause issues later, or maybe you are having issues now.

Just try it to see if the noise goes away.

If you cannot find anything close to connect the spring to, make a tang that goes on the closet transmission bolt that has a small hole for the spring to connect to.

[PAwelder]

thats a good idea, i attempted to jiggle the arm today right after i started it, it ended up going away before i could drag my self under the truck. Ill rig something up tonight and test it next year after it sat for a night. Happy new year members of Ratsun! 

[PAwelder]

she squealed long enough the one morning and i managed to get under neath and see whats going on. By pushing the fork and compressing the slave, moving the t/o bearing away from contacting the fingers the noise stops and also going the opposite direction and applying pressure to the t/o bearing it goes away as well, so i can now say that it is the throw out bearing making noise. 

[datzenmike]

The fluid will have some weight and gently push the slave push rod towards the clutch arm. This is not enough to move the arm or very slightly. IF the arm was forward enough for the release bearing to rub the diaphragm fingers it would never be enough to wear the bearing out. Only a significant load might do this, like constantly resting your foot on the clutch pedal. This is a large robust bearing and could spin forever without a problem... just not loaded.

 

Are you sure you replaced it, as it shouldn't be making noise in less than a month, even if abused!

Does it have the correct collar length? Too long would force it against the fingers.

Did you press the bearing on facing the correct direction?