FJ40 3speed to 4speed Clutch Problems... HELP! (1 Viewer)

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gravity bleed your MC till it drips from line to SC

***manually depress/push in... your slave piston

attach line from MC to SC

***ensure all push rods are the same length as the parts removed

bleed
 
I really really appreciate everyones input. I do.

I realize if the slave still only travels 1/2 inch, it's not in the bell housing. It can't be. I'm getting two of my most trusted brain trust guys over here soon with a all eyes on meeting to get this figured out.

The MC rod is adjusted to .5mm travel. It isn't there. I removed the boot to see that the piston was out to start.
When I installed the SC, I removed the boot and shoved the piston all the way back. Then when installing adjusted the nut almost as far as I could and still have enough threads inside the nut. The slack was at most an 1/8 inch. That adjustment isn't as obvious a result as up top.

I've slept since then so I'm more clear minded today. No pulling the drive train until no other option. Please, God!!
 
Is your slave bleeder on the "top" or "bottom" side of your cylinder as mounted. Some of us are running the slave mounted upside down where the bleeder is on the bottom of the cylinder. I bleed my slave by gravity, but with the cylinder removed from its mounted position and just hanging by the hose so that the bleeder is at the top.
 
Bleeders should always be on top. Air floats. That way, the air has a natural way to travel out with bleeding procedure. Just like brake calipers.

Yes. It's on top.
 
Question: you tested and the slave is not only moving 1/2 inch when not installed and pressing on the release fork? You might have mentioned that you tested the system when not bolted to the truck but I may have missed it...
 
Somewhere in the middle of all this, yes, I unmounted the slave and checked the distance without any back pressure.

Same result.
 
Full pedal stroke.

Keep 'em coming boys, at some point we'll get this figured out.
 
Are there differences in pedal or mounting locations of some sort for the different years? What I’m wondering is; is the hole in the pedal for the MC pushrod in a different spot early vs late. If you were using a pedal and the hole was higher up, you’d get less travel of the mc and less fluid movement probably leading to less slave cylinder travel.
 
I feel fairly certain the hole in the pedal is in the same place.First, there's no reason to move the MC because os the ribs in the firewall. Second, the push rod has to be strait, level, and perfectly horizontal. So the hole is the same hight. If it moved back any on the pedal, the adjustment would take it out.

I woke up this morning and the first thought was of a potential fix. I won't write it here now since every other idea has failed. I'll report back if it works.
 
Just a sanity check Rainey, what bellhousing, clutch fork, flywheel and clutch setup are you using? Are they all from the same year model?
 
'76 from the cooling fan to the output shaft of the transmission. '70 t-case. And now new MC and SC for a '76.

My great idea that wasn't great enough to fix the issue was to bench bleed the master again. This time... Start with the pedal on the floor. Fill the reservoir and slowly let off the pedal. Figured that would remove most of the air to start with and pull the fluid back with the piston. Then pump until all air was out. Looked like a great idea at the time.

Same.

Your sanity check came at the right time. Saturday night I was at my worst. Pizza and beer then a movie to take my mind off did the trick. Now I'm just a little numb from the constant :bang: . Nearly 2 weeks going now...
 
Another maybe-just-maybe-probably-not question; did you catch in the FSM graphic shows the floor mat and/or sound deadening pulled back and indicates the measurement is from the metal? It is probably an inconsequential distance, I just remember that they went to the trouble to graphically illustrate it. My brake and clutch pedals are the same height when everything's working properly.
 
Have you got a better picture of the SC? In the picture on page 1 it looks like the boot on the SC is angled up, like the clutch fork is not in the same horizontal plane as the SC. In my experience they should be aligned with each other and almost level.
 
The manual says 8.5". There is no possible way in my truck to get there. It's 6.5" and just a tad higher than the brake pedal. Remember, this truck had a working clutch before I swapped out the dead engine.

As far as the push rod angle is concerned, I noticed the boot axle earlier too but it's either an optical illusion or it was hung on the spring. This shot isn't much better but it shows that it's straight.
IMG_1177.jpeg
 
The manual says 8.5". There is no possible way in my truck to get there. It's 6.5" and just a tad higher than the brake pedal. Remember, this truck had a working clutch before I swapped out the dead engine.

As far as the push rod angle is concerned, I noticed the boot axle earlier too but it's either an optical illusion or it was hung on the spring. This shot isn't much better but it shows that it's straight.
View attachment 2469652

Lots of eyes in this thread, notice @Coolerman ‘s slave orientation

 
I have several clutch forks laying around. I decided to check and see what the difference was between the 3 and 4 speed arms. Other than the dog leg in the 4 speed version, the distances between the bearing mount, the pivot point, and the SC rod capture hole are exactly in the same positions. Same distances between too. The 4 speed fork is lust a little closer to the SC. With the exhaust right under it, it's tough to get a good look but everything seems to line up vey well to me. And I'm a perfectionist.
 
I have several clutch forks laying around. I decided to check and see what the difference was between the 3 and 4 speed arms. Other than the dog leg in the 4 speed version, the distances between the bearing mount, the pivot point, and the SC rod capture hole are exactly in the same positions. Same distances between too. The 4 speed fork is lust a little closer to the SC. With the exhaust right under it, it's tough to get a good look but everything seems to line up vey well to me. And I'm a perfectionist.

If your clutch pedal is only 6” above the floor something isn’t right. What was that measurement before you swapped in the 4 speed when it was driving?
 
6".

In this truck, there is no possible way to raise it any higher. Same with the brake pedal. I've adjusted to clutch pedal as far as I can so it's just a touch higher than the brake pedal but not noticeable.
 

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