LJ70 clutch seems "inactive". Car has a hard time shifting into gears until warm. Elaboration in txt (1 Viewer)

[DanishLJ70]

So, first of all: this is a x-post from /r/LandCruisers. I hope this is allowed.


As the title says, my LJ70 has a really weird problem with the clutch. It is as if the clutch is inactive in some way. When I push down the clutch pedal, it moves very freely with no resistance at all, until an inch from the floor. This also means that the car has a really hard time shifting into gears when cold or after driving in the same gear for a longer period, i.e. after highway/freeway driving. This problem disappears during city driving, though. I'm guessing it warms up the transmission and clutch, and this helps with mobility, but I really have no clue.

"Hard time shifting into gear" meaning that I have to push really hard to get it into gear. 1st gear is typically harder than 2nd gear, though. It can, however, shift from gear into neutral without any problems at all.

Another thing that makes it feel like the clutch is inactive (I know this isn't the proper term, but english is not my native language and I say this in lack of better words), is that if I am parked in 1st gear, with the clutch pressed all the way down to the floor and I lift my foot off the brake, the car will start moving slowly forward at idle, even though I'm stepping on the clutch.

My first thought was that maybe the clutch was dead, but as I mentioned when the engine (and transmission, I suppose) gets warmed up it has no issues shifting between gears at all. Also, I have experienced in other cars that a worn out clutch will often result in the engine revving without the car accelerating accordingly - this has never been an issue with my LJ70. It revs and pulls perfectly fine and revs and acceleration is perfectly aligned. It also doesn't smell weird like a burnt/worn clutch tends to do, even after longer/harder drives and tows.

Does anybody have any idea what this could be? Can the cable from the clutch pedal to the actual clutch need tightening, like the handbrake? Is my transmission dead?

Thanks a lot in advance!

 

[kbushnz]

Hi Yah... The clutch system on the LJ70 is supposed to be a hydraulic setup. So with that in mind check the fluid levels and then bleed the system. Just like doing the brakes.
Look for leaks. This is normally a two person job. Also while someone is under the truck you can watch the clutch fork moving when the clutch is depressed. Worst case scenario you have a leak or the master / slave cylinders require new seals or replacement.

 

[jblueridge]

Does you clutch pedal push on a hydraulic master cylinder like your brakes or is there really a cable?

I would check to make sure there is enough fluid in the clutch master cylinder. Maybe there is air in the system that needs to be removed by bleeding.

If there really is a clutch cable, it should be adjustable.

 

[DanishLJ70]

Hi Yah... The clutch system on the LJ70 is supposed to be a hydraulic setup. So with that in mind check the fluid levels and then bleed the system. Just like doing the brakes.
Look for leaks. This is normally a two person job. Also while someone is under the truck you can watch the clutch fork moving when the clutch is depressed. Worst case scenario you have a leak or the master / slave cylinders require new seals or replacement.

Hi! Thanks a lot for your advice. I'm really paranoid about leaks with my cars, always has been, so I look for leaks under the car almost daily, or whenever I leave it parked somewhere/return to it. I have never seen any leaks of any kind whatsoever while I've had this truck, and this problem hasn't been there the whole time. Will these fluids typically leak only when driving? How/where do I check the fluid levels? I'm still somewhat new to these kinds of cars, and not really mech savvy like a lot of you folks, so I'm still learning. Again, thanks a lot!

 

[DanishLJ70]

Does you clutch pedal push on a hydraulic master cylinder like your brakes or is there really a cable?

I would check to make sure there is enough fluid in the clutch master cylinder. Maybe there is air in the system that needs to be removed by bleeding.

If there really is a clutch cable, it should be adjustable.

Hey! I'm pretty sure it actually pushes on a hydraulic cylinder, now that I think about it. Excuse the probably stupid question, but where do I check the fluid level for the master cylinder? I haven't had to do this before on any car, so I have no idea. Thanks a lot, by the way

 

[kbushnz]

Download this manual and it will have all the info you require.
http://daemon4x4.org/portal/downloads.php?ttid=255

Its a bit torrent so you will need to torrent software loaded.

 

[jblueridge]

Open the hood/bonnet. Look for the clutch master cylinder forward from the clutch pedal.
The cap does not unscrew. Just peel it up and off.
The fluid inside is brake fluid; it eats paint so be careful and have rags or paper towels ready.
The clutch master cylinder has only one small metal tube coming out of it. (The brake master cylinder is similar but larger and it will have two little tubes attached.)

Here is a pic.

 

[DanishLJ70]

Download this manual and it will have all the info you require.
http://daemon4x4.org/portal/downloads.php?ttid=255

Its a bit torrent so you will need to torrent software loaded.

Thanks a lot! I'll download this and look into it today.

 

[DanishLJ70]

Most of the time when the clutch master cylinder shoots out and leaks it leaks into the vehicle and is not easily seen until it presents a mechanical problem. If the fluid is low check under your drivers side carpet for a not so nice surprise

I guess I'll have to look under the carpet. I'm partly hoping for a not so nice surprise, and partly not. If it leaks, then what? New clutch? New master cylinder?

 

[DanishLJ70]

Open the hood/bonnet. Look for the clutch master cylinder forward from the clutch pedal.
The cap does not unscrew. Just peel it up and off.
The fluid inside is brake fluid; it eats paint so be careful and have rags or paper towels ready.
The clutch master cylinder has only one small metal tube coming out of it. (The brake master cylinder is similar but larger and it will have two little tubes attached.)

Here is a pic.
View attachment 1302615

Thanks a lot for your explanation! If the fluid level is low, can I solve the problem temporarily by adding fluid until I'm able to work on it?

 

[Locked79]

Yes, if the fluid is low you just add some until full. You may have to bleed the system to get the air out and working properly.

The symptoms you describe would lead me to believe its a hydraulic problem, and not a problem with the clutch itself. If there are no external leaks and the fluid is full, I would be looking at the clutch master cylinder. Reletively cheap and easy to replace.

 

[DanishLJ70]

Yes, if the fluid is low you just add some until full. You may have to bleed the system to get the air out and working properly.

The symptoms you describe would lead me to believe its a hydraulic problem, and not a problem with the clutch itself. If there are no external leaks and the fluid is full, I would be looking at the clutch master cylinder. Reletively cheap and easy to replace.

So, I just checked and the cylinder is completely empty. Like, there's no fluid in it at all. There is, however, a small black circular plastic/rubber piece in there - I'm guessing it is some sort of floating device?
I also pulled the carpet and it was completely dry and not greasy at all, so I don't think it has leaked into the interior - but the fluid won't just be used up over time, would it?

If it is leaking then it would be time for a new clutch master cylinder. If you have to replace it do yourself a favor and replace the clutch master cylinder at the same time. Often replacing the master will expedite the failure of an older slave. The slave is not that expensive and quite easy to change.

I can't tell if it has been leaking anywhere - I only know that it hasn't been leaking into the interior. My next step is going to refill the fluids on it and check daily if it's getting lower on fluid. When refilling, is there a certain proper way to go about it? Or do I just fill it up, pump the pedal a few times and check if it needs more fluid?

 

[jblueridge]

Rob is right that the system needs bleeding. You can use youtube to see more about bleeding brakes: the clutch works the same way.
The slave cylinder is bolted under the vehicle. You have to crawl under to see it well. On my vehicle, the clutch slave is on the left side (sitting facing forward)
It has one rubber hose going into it, less than 1cm in diameter.
The hose looks like this: It might be dirty and wet.

Slave looks like this but it will be dirty and maybe wet with fluid.

 

[DanishLJ70]

well there are only three places it can leak from, the master, slave and the line between them. If you refill it you will need to bleed it, not simply just pump it up. the bleeder valve is on the slave. If you refill you should be able to find where it is leaking from but I still deal with the master and slave as one unit when replacing rather than two individual pieces. YMMV

Rob is right that the system needs bleeding. You can use youtube to see more about bleeding brakes: the clutch works the same way.
The slave cylinder is bolted under the vehicle. You have to crawl under to see it well. On my vehicle, the clutch slave is on the left side (sitting facing forward)
It has one rubber hose going into it, less than 1cm in diameter.
The hose looks like this: It might be dirty and wet.

Slave looks like this but it will be dirty and maybe wet with fluid.

Thanks a lot for telling me this. Can I refill the master cylinder as a bandaid solution until I'm able to bleed it? I'm not able to work on it where I am right now, and I'm guessing it's still better than driving without any fluid in the master cylinder? I feel like this will put a lot of wear on my transmission.

 

[jblueridge]

I think the worst that will happen is the clutch will not work at all. Your problem seems to be with the hydraulics; the parts that make the clutch move. The clutch itself and the transmission are not broken. If they are, you have two separate problems.

 

[Locked79]

@DanishLJ70 Since you still have some clutch action, this tells me that there must still be some fluid in the master cylinder bore, though the reservoir is empty. Refill and see what happens. If there's no air further down the line, the air in the master may well bleed out by itself. If not, bleeding will be necessary.

Yes, the black disc is a float. And as the others said, the clutch hydraulics is a sealed system. If the fluid is low, there is a leak somewhere. They don't "use" any fluid.

 

[richmason]

I just had this issue on my LJ70 after a clutch replacement. The slave cylinder was leaking but keeping the fluid inside the boot. When it was cold, it wouldn't work at all but once warmed up it worked like new. Replace the slave cylinder and you will be good to go.

 

[CRZR45]

Looks like you have a power booster on your clutch.Is the slave cylinder(one that pushes the clutch fork on trans) wet or leaking? If not your master (one on firewall attached to booster) is bad and instead of leaking into the cabin and floor it's filling your booster which is not good since it will ruin the booster if left in fixed..my 2c