1986 Nissan Truck - Clutch Question

Yes, check the clutch slave cylinder on the outside of the transmission case. Odds are the seal has gone bad and leaked out all the brake fluid from the reservoir. Piece of cake to either rebuild (if you have a small brake cylinder hone you can probably just grab a rebuild kit from Nissan for next to nothing, it has a seal and the dust boot) or just replace it. Bleed the system with the help of a friend and you should be back in business.

Wil

Thanks,

Do you happen to know where to find the reservoir that feed the slave cylinder? I can check to see if it is empty.

JW

It's located, if I remember correctly, on the firewall, close to the brake master cylinder. It's a small, single reservoir. Let us know what you find out. Good luck,

Wil

I think I found the reservoir. It is about 1" to 1-1/2" in diameter and about 3" high -- a white plastic cylinder that sets against the fire wall to the right of the Master Brake Cylinder when looking in from the front. It has markings on the side of the cylinder full half full and empty.

If that is indeed the Clutch Reservoir -- it is completely empty.

Can I just fill this up and pump the heck out of the clutch to see if that fixes it. Or do I have to bleed the line? Which by the way I have no clue on how to do this.

Also what goes in there. Is it brake fluid or is there a clutch fluid I need to get?

Thanks and sorry for my ignorance.

JW

Sounds like you found it.

There's probably a leak or blown seal somewhere if it just leaked out all at once like you describe, but considering the relative ease and cheapness of refilling the system, it would probably make it easier to find the leak.

According the the (Haynes) manual for my 94 Altima, it's regular brake fluid, and the procedure is:

1- Fill the reservoir 2- Have a helper press the pedal and hold it to the floor 3- Open the bleeder valve on the slave cylinder until air and/or fluid stops coming out 4- Tighten the valve

Repeat 2-4 until only clear fluid with no bubbles comes out.

It says you should have a length of hose fit on the end of the bleeder valve, with the other end in a few inches of fluid in a conatiner of some kind.

Hope this helps, and good luck!

diameter

Master

cheapness of

bleeder

Thanks every one for the help. I haven't been under a car or truck for years. It will be an adventure. I'm the original owner of the truck and it only has 65,000 miles on it. I was thinking about trading it in. In fact, I was going to drive to the Nissan dealer this morning to see what I could do on a close out 2004, when I found the problem with the clutch. I ended up diving my Subaru. It turns the deals you read about in the paper seem to evaporate when you get to the lot. I'll probably fix up the 86.

Thanks again, JW

You might try just filling it up, pull the pedal up to it's normal "up" position and let it sit over night. On some cars the air will rise to the top and "self bleed".

truck

Thanks Steve and everyone who responded to my post.

I'll give that a try.

JW

Blown seal, refill reservoir on firewall, pump it up and watch for leaks. Didn't you see any leaks on the ground wher it was parked?

seemed

without

You kind of have to be here to see where it is parked to understand. I only drive it once in a while and it is parked in a corner of a lot with some high grass. It is blocked in by another car. I did look under there but I need to clean up the area around the truck in order to get a good look and now I can't move it out because of the clutch.

JW

JW

That's the reservoir. :-)

Yeah, the fluid all went somewhere and my money's on that seal. Like others have mentioned here, put some brake fluid (DOT 3 approved is all you need) in the reservoir and have a helper work the pedal up and down with their hand a number of times while you watch underneath. I'll bet you soon see some dripping or a steady stream. If you don't feel comfortable replacing the unit, just completely fill the reservoir and the seal *may* hold pressure long enough for you to get to the dealership to have it changed.

I can't remember if the slave cylinder mounted to the transmission has one bolt or two holding it on, but aside from that and disconnecting the line to the cylinder, that's really all there is to change it out. Just bleed afterwards (it's the only way to remove the trapped air), as was also mentioned elsewhere here (everyone is so helpful here :-) ), and you're good to go another 65,000+. :-)

Wil

Everyones forgetting the clutch damper on the right side of the firewall has to be bled FIRST! Then the slave cylinder.It is the square box with a line coming accross the top of the fire wall from the clutch MC then it has a line going to the slavre cylinder.

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don't

I went out this morning an bought some Dot3 filled the reservoir up to the top line. Cleared an area on the side of the truck so I could reach in and see underneath the rubber boot at the far end of the cylinder. I then pumped the clutch pedal more time than I'm sure is necessary. What I found is as follows:

1. The fluid level went down about a half an inch.
2. Squeezed under the truck and could find no signs of a leak on the ground.
3. Pulled the rubber boot back and stuck my finger in and felt around. I could find no signs of fresh fluid. what I did find is enough really gummy old fluid to make my finger really dirty. A gummy oily dirty.
4. Pumped the pedal a lot more times and nothing seems to change.

I will have to wait for the wife to get home this tomorrow so she can pump the clutch while I see what is going on underneath. Actually I'm not sure what to look for now.

It may be that the 1/2 inch of fluid that went down after the initial filling simply went into an empty line.

Could it just need bleeding now?

What should happen underneath. I would guess that every time the clutch petal is pushed down the rod at the end of the cylinder should travel some number of inches.

So this leads to the questions.

1. If it travels does that mean there is something wrong inside the transmission.
2. If it does not travel there is something wrong within the cylinder?

Sorry about the long post. I appreciate your help.

JW

firewall

How does one bleed this. Would I remove the line from the output of this damper box and push some fluid through.

I was following the line from the MC and wondered what that little box was for.

Thanks,

JW

Your symptoms were diagnosed based on the loss of fluid. A hydraulic clutch is not some mysterious device only understood by the finest mechanics. You'll need to determine where the fluid leaked from. The clutch slave, master or both. I would think you could find either one priced under $75.00 US.

underneath.

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cylinder?

When I first opened the MC it was bone dry. I filled it up and pumped the clutch. It went down about 1/2 inch. I then filled it to the max level. I have pumped the clutch a lot. I have held the clutch in for a long time. The fluid level is not decreasing. I removed the rubber boot from the slave and there was gunk but it appears to be old oil. I check along the entire line from the MS to the slave and have found no sign of leakage. I am assuming that the fluid has been leaking slowly for a number of years. I don't know if anyone has ever checked the MS fluid level. I know I haven't since 1986. So it has fluid now but still no clutch. My question is could it just need bleeding at this point or maybe a linkage problem from the pedal itself? I realize that I could easily go out and bleed the thing but I'm waiting for my helper to return from a trip. The question is out of curiosity. I actually called Pep Boys and they range from 19.95 to 40.00 depending on the engine model.

Thanks, JW

Probably should replace the master and slave. If something leaked, it's going to happen again even at 65K miles

I priced a clutch kit for a 2WD 720 with Z24 motor and it was like 500 bucks.

Holding the clutch in does nothing. Unless the pedal is sitting at the upper stop, the air can't escape. If it's going to....