4+3 Clutch Problem
Thread Starter
Pro
Joined: Sep 2024
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4+3 Clutch Problem
Hey All,
I want to bounce something off you fellers here.
I have an 87 with the 4+3 and replaced the following:
But I am still having a problem getting the clutch to disengage with the engine running. I can cycle through all the gears no problem with the engine off and the clutch feels like it is working, but not with the engine running. I have used my pressure bleeder and have ensured that there is no air in the lines.
One thing I can't tell is if the rubber piece on the master to slave line is restricting fluid flow enough that it is not fully disengaging the clutch. I know lots of rubber lines do constrict with age on brake lines and I assume this can happen in a clutch line too.
Have any of you had to replace the clutch line because of this situation? I am thinking that this is the only answer to this conundrum since I have replaced every other part in the system.
Just spitballing here. The line is pretty expensive so I may pull it out and take it to a Parker store and see if they can replace the rubber section.
Thanks for the help!
Paul
I want to bounce something off you fellers here.
I have an 87 with the 4+3 and replaced the following:
- Flywheel
- Clutch
- Throwout Bearing
- Slave Cylinder
- Master Cylinder
But I am still having a problem getting the clutch to disengage with the engine running. I can cycle through all the gears no problem with the engine off and the clutch feels like it is working, but not with the engine running. I have used my pressure bleeder and have ensured that there is no air in the lines.
One thing I can't tell is if the rubber piece on the master to slave line is restricting fluid flow enough that it is not fully disengaging the clutch. I know lots of rubber lines do constrict with age on brake lines and I assume this can happen in a clutch line too.
Have any of you had to replace the clutch line because of this situation? I am thinking that this is the only answer to this conundrum since I have replaced every other part in the system.
Just spitballing here. The line is pretty expensive so I may pull it out and take it to a Parker store and see if they can replace the rubber section.
Thanks for the help!
Paul
Racer
Joined: Oct 2023
Posts: 383
Likes: 123
From: St. Petersburg, FL
I can say from my previous clutch replacements on a 4+3 is that you need to “work it in”. When I first tried to use the new clutch it grinded and wouldn’t go into gear and the clutch felt horrible. Basically keep using the clutch, and move the gears into 1st and reverse and drive it. I’ve had issues after replacing the flywheel and clutch on a 4+3, it will get better.
Melting Slicks
Joined: Aug 2003
Posts: 3,399
Likes: 394
From: Lakeville MI
Can you start it in gear with the clutch disengaged without the car moving and driving off? Be careful in the event that the clutch really is engaged, since you might be going for a ride until you shut it down or stall it.
Thread Starter
Pro
Joined: Sep 2024
Posts: 526
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I can say from my previous clutch replacements on a 4+3 is that you need to “work it in”. When I first tried to use the new clutch it grinded and wouldn’t go into gear and the clutch felt horrible. Basically keep using the clutch, and move the gears into 1st and reverse and drive it. I’ve had issues after replacing the flywheel and clutch on a 4+3, it will get better.
Thread Starter
Pro
Joined: Sep 2024
Posts: 526
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From what I am gathering, this Bruce Jenner has a few qualities that deviate from the norm. I will definitely report back if I get no love once I get it running again.
Thanks gents!
Team Owner
Joined: Jan 2003
Posts: 20,316
Likes: 246
From: Summerland B.C. Canada
I recall that for some reason, I needed to make the push rod from slave, slightly longer.
That was 20 years ago, so I don’t recall if I made a new push rod or added some metal(mig weld) to existing rod.
Have a close look and see if there is any free play between fork, rod and slave.
It’s a fine line between engaged and released.
That was 20 years ago, so I don’t recall if I made a new push rod or added some metal(mig weld) to existing rod.
Have a close look and see if there is any free play between fork, rod and slave.
It’s a fine line between engaged and released.
Melting Slicks
Joined: Jan 2014
Posts: 2,192
Likes: 381
From: Lunenburg MA
As is says in the manual, you need to remove the slave, Hold in your hand at a 45 degree angle with the bleeder up. Push the piston all the way in then open the bleeder and let gravity bleed it. Trying to bleed it bolted in place will drive you mad.
Thread Starter
Pro
Joined: Sep 2024
Posts: 526
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So I am guessing that with it installed on the car, the bleeder is not at the top of the cylinder. Thanks for the tip!!!
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Burning Brakes
Joined: Jun 2005
Posts: 1,191
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From: Wallingford Vermont
Funny you mention that. More than twenty years ago, a friend was helping me change the clutch on my '86. I can't remember exactly but I think we had the flywheel turned (maybe) and ran into the pushrod length issue. He had some type of rod he rigged to work, I think I still got it
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Is there a way to put it in wrong? I mean, I know I am capable of screwing anything up, but it isn't unique in any way from other hydraulic throwout bearings, is it?
Advanced
Joined: Apr 2025
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Yes, there is lol. I installed the bearing on the arm by clipping it in on the lip at the rear of the bearing. The arm and clips go into the slot on the rear of the bearing. I did not realize this until looking at the paperwork that came with the McLead clutch.
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Yes, there is lol. I installed the bearing on the arm by clipping it in on the lip at the rear of the bearing. The arm and clips go into the slot on the rear of the bearing. I did not realize this until looking at the paperwork that came with the McLead clutch.
EDIT: Yeah, its just a standard TOB. I had mine in the slot like they all should be.
Last edited by marshallnoise; Jun 23, 2025 at 12:37 PM.
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Joined: Sep 2024
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Yeah, brand new flywheel and clutch so that ain't it. Thanks for the note on the longer pushrod!
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Joined: Sep 2024
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Well, I finally figured out what went wrong. It was the brand new clutch line I paid $189 for. I got it from eBay, but a seemingly reputable parts seller who advertises these as brand new. The manufacturing date was 11/21 so it had been sitting on the shelf for a few years. But the real culprit was the rubber section of hose they used. I could not get any air through there, carb cleaner wouldn't touch it and when I used a fat guitar string to attempt to clear it, the string stopped hard as soon as it got to the rubber section. I looked at the date on the rubber and it was 2016.
At least I am not on crack...for that reason.
At least I am not on crack...for that reason.
Pro
Joined: May 2025
Posts: 613
Likes: 146
From: OK
I bought one from Top Flight that was made by Corvette Stainless Steel Brakes or some such, mostly because they were the only one that would express ship it for reasonable money.
Other than the steel needing a little tweaking to fit right, and my early 86 using the 85 style line, it seems to be working.
Another thing I saw with mine is it needed a taller throw-out bearing, with just all new stock stuff (mcleod clutch n iron flywheel) at max stroke the slave piston was on the snap ring and the arm was
touching the rear of the bellhousing where it exits out of it. Taller TO bearing put it all back in the middle of it's range of motion and seems to be working thus far.
I killed a new slave in this thing inside 50 miles with the previous sachs clutch, visible scuffing on the piston and slave cylinder inner wall, and I hope this corrects the geometry some.
IMO this is a crappily designed system all around and/or all the replacement parts are crap.
Other than the steel needing a little tweaking to fit right, and my early 86 using the 85 style line, it seems to be working.
Another thing I saw with mine is it needed a taller throw-out bearing, with just all new stock stuff (mcleod clutch n iron flywheel) at max stroke the slave piston was on the snap ring and the arm was
touching the rear of the bellhousing where it exits out of it. Taller TO bearing put it all back in the middle of it's range of motion and seems to be working thus far.
I killed a new slave in this thing inside 50 miles with the previous sachs clutch, visible scuffing on the piston and slave cylinder inner wall, and I hope this corrects the geometry some.
IMO this is a crappily designed system all around and/or all the replacement parts are crap.
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Joined: Sep 2024
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I went to Crown Performance and this time, they were able to come up with a solution for me. I have flaring tools so I will be cutting off the rubber section and replacing it with a stainless steel flexible hose. Finally, I can move on from this frustration!