Clutch slave adjustment (1 Viewer)

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I've been trying to adjust the rod length on the slave. My clutch is high, really high, like the first 2-3 inch on the pedal travel is enough to engage the clutch.

So i reduce the rod length, i then get a small 1/8" play between the rod and the fork. But obviously if i go press the clutch the slave will only take this play and the play will be gone. consequently only moving the slave piston toward the fork. Seems to me doesn't mather how short the rod is the piston will compensate the play?

This high clutch has been driving me crazy. Clutch was replaced 6 month ago. A new Master clutch was installed couple weeks ago and slave maybe 2 years ago all with OEM.

Is there a step by step instructions to adjust everything?
 
Check your pedal adjustment. Here's the specs from FSM.
ClutchAdjust.jpg
 
Check your pedal adjustment. Here's the specs from FSM.

Yeah, problem is if i adjust the slave to 3-4 mm, after a couple of press and release of the clutch the play is gone and the slave piston simply took the play. Unless i'm totally stupid and i don't get what they mean by play. Is it the play or movement of the fork, or the play of the push rod?

EDIT: couldn't be clearer, "Release fork end play"

Will check again, but from what i remember, after press and release a few times, there are no play anywhere anymore.
 
That's the nature of hydraulics. Gently push the slave rod into the cylinder and then set the play at the fork. When you press the master cylinder the play is going to go away.....this is correct. Now adjust your pedal....the push rod between the pedal and the master to get rid of the "high pedal" that's driving you crazy. :cheers:
 
That's the nature of hydraulics. Gently push the slave rod into the cylinder and then set the play at the fork. When you press the master cylinder the play is going to go away.....this is correct. Now adjust your pedal....the push rod between the pedal and the master to get rid of the "high pedal" that's driving you crazy. :cheers:

Will do, but even if i adjust the rod end on the master, i'm going to move the high pedal, not the high clutch on the pedal stroke!, you see what i mean? i think adjusting the rod end will simply reduce or increase the clutch pedal stroke and not a high clutch. i guess its hydraulics and maybe you simply cannot adjust where the clutch engage in the pedal stroke.
 
Hi,

I'm seeing the exact same symptoms as eleblanc with my clutch. It engages within the first few inches of pushing in the clutch, rather than towards the bottom of the stroke. Similar to eleblanc, I have adjusted pedal height and both master and slave cylinder push rods, but the problem still exists. My pedal height is spot on at the moment, so if I further tighten the master rod, it will only pull my pedal closer to the floor. Slave rod is also at maximum adjustment, but as called out before, even if I could shorten the rod further, it would only be absorbed by the slave hydraulics with the first push of the clutch. The one thing I should note is that both the clutch cylinder and slave are an aftermarket set from CCOT (purchased before I learned the value of OEM). My rig is a 11/72, where as the slave cylinder is (according to CCOT) is a 74+ unit. The slave unit looks identical in dimensions to my original, so I wouldn't think this would matter, but wanted to call it out.

Thanks in advance. I'll post a follow-up once I resolve.

CCOT Unit: Clutch Master Cylinder
Clutch Master / Slave Cyl - Conv. Kit - '58 to 8 /74
Early model (8/'74 & Older) slave cylinders conversion... $Save! Now you can convert your '74 and back FJ40 to use the '74 and up slave cylinder. This kit comes with new master cylinder, new slave cylinder and new hydraulic line linking master to slave (all parts shown). Works with Land Cruisers where the slave cylinder mounts on the driver side.
 
There are 3 pieces to this puzzle.
1) Pedal stop, which is something that holds your pedal at rest.
2) Free-play, which means when your pedal is at rest the clutch MC is not being pushed in.
3) Clutch MC travel, which is the distance the rod has to travel to release pressure on the clutch.
So if you want to move your pedal down then do 1,2,3.
1)Set a new stop for your pedal at rest. 2)Modify the rod so that you have free-play. 3) Make sure your pedal travels far enough to operate the clutch. Obviously if you move the pedal down too far you won't have enough travel.
 
Thanks FJforty. I think I'm clear on the three points you note; however, to increase free-play the MC rod can only be shortened so far before you're forced to lower the pedal height as rod will start to pull down the pedal. I suspect I'm not getting something, but this is what I'm finding. With your rig, does your clutch engage towards the floor?
 
My clutch engages about 1.5 inches from the top. I don't like it engaging there and I want the pedal further down at rest. I am not trying to change free-play. Free-play is what the MC needs so the rod does not push on it while at rest. I am trying to change the rest position of the pedal so the pedal rests further down and still have 1.5" of engagement. I plan on the same for the brake pedal. If you just want to change where the clutch engages then I don't know but I believe it will be tough because that is the hydraulic part.
 
My clutch is similar in that it engaged 1.5 inches from the top, so maybe it is functioning as designed. I'd be curious if others see the same. With the FSM specifying an exact pedal height, I was trying to maintain the correct height while lowering the point where it engaged (say 2-3 inches from the floor). I'll probably lower the pedal an inch and see if it feels better. thanks.
 
This may not mean anything but mine was engaging within the last 2-3" of travel towards the top, today I bled the clutch/new fluid and now it engages more toward the bottom as you start to release it from the fire wall...weird?
 
Often with a new clutch there won't be much adjustment room at the slave rod. You'll develop later (deeper) disengagement as the clutch wears. Not saying it's right but I have had it happen on more than one vehicle.
 
The clutch in my 45 was engaging right at the top of the pedal travel. If I just touched the pedal it would start to slip. I didn't like this at all, so I adjusted the pedal per the fsm and then adjusted the slave rod to engage the clutch much sooner. It now engages about 2-3" off the floor and has the correct free play at the top. Much better.
 
With regard to pedal height, I see different specs between my FSM, Haynes manual and the diagram shown earlier in this thread. I have a 73 FJ40 w/ brake booster. The diagram provided by cmiller114 above indicates 7.64in to the floor. My FSM (printed '72) states 9.65" to the firewall , which seems in line with 7.64” to the floor. My Haynes manual states 8.6" to floor (FJ w/ booster) or 7.65 (FJ w/o booster). My 73 has a brake booster and the original height was closer to the 8.6” specification in the Haynes manual, so I suspect this is how it came from the factory.

I tried adjusting down to the lower setting, but was only able to get to around 7.5" with the clutch and 8.25" with the brake before running out of adjustment on the master rods. I then compromised to bring both brake and clutch at 8.25”. Since I ran out of adjusting rod w/ the brake, I suspect the official spec for my rig is the higher number listed in the manuals, but I left it at 8.25" as it feels better to have the pedals lower to the floor and everything still functions as normal. At this point I'm going to leave things as-is unless I hear otherwise, but wanted to share my findings.

thanks,
Brian
 
Mine was high before i replaced it and still was high after new clutch and transmission. Did tons of adjustement and never really was able to revert it to a low position instead of high. At best i adjusted the high position a bit. I'm just use to it, but the few who got a chance to drive my BJ and own a 40 all commented that my friction spot was high!

NOTE that when i say high i mean high on the travel of the pedal. Obviously you can physicly lower the friction spot with pedal rod.
 
I had a similar problem.My slave rod would not fully return back into the cylinder.I rebuilt it twice and spent 2 days trying to figure out the problem.After I cracked the line at the master and pushed the slave rod in by hand(reverse bleed).it mysteriously started to work correctly.Good luck:)
 

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