Clutch issue

-
RAT ROD AL

RAT ROD AL

MOPAR ARCHAEOLOGIST - one parts hoard at a time!
FABO Gold Member
Joined
Jan 18, 2013
Messages
7,949
Reaction score
10,741
Location
Lecanto Florida
I have a new clutch assy with a 3 finger P/P on my 833. The pedal only comes up off the floor about Half way and the throw out bearing stays engaged . I have to pull it up with my toe each time. The big heavy return spring is still hooked up under the dash. What's the deal ?
What do I have wrong ?
 
Pull the inspection cover and look at the gap between the throwout bearing and the pressure plate fingers. The air gap should be a 1/4" or so. If all springs are in place you should be good.
 
If the clutch has softer pedal effort than the old clutch it may need a stiffer spring on the clutch fork to help the other spring return from over center.
 
If the plate load is LESS than OE you need to REMOVE the over center spring or the clutch will not return to the stop.

If it won't come back and everything else is correct, remove the over center spring.
 
Last edited:
66signet said:
I had that on my 66 Valiant. I replaced the bushings on the z bar and that fixed the problem.
Click to expand...
It has good bushings all lubed up on installation.
yellow rose said:
If the plate load is LESS than OE you need to REMOVE the over center spring or the clutch will not return to the stop.

If it won't come back and everything else is correct, remove the over center spring.
Click to expand...
I will check to make sure I have the fork spring on correctly, now if I remove the over center spring and then that doesn't help, I understand that they are a :mad: to put back on if I need to.
 
There’s an article in the tech pages on how to put thick washers between the coils on opposite sides of the spring to stretch it to aid in removal.
 
yellow rose said:
If the plate load is LESS than OE you need to REMOVE the over center spring or the clutch will not return to the stop.

If it won't come back and everything else is correct, remove the over center spring.
Click to expand...
Only if you change to a diaphragm pressure plate.
 
yellow rose said:
If the plate load is LESS than OE you need to REMOVE the over center spring or the clutch will not return to the stop.

If it won't come back and everything else is correct, remove the over center spring.
Click to expand...

The previous owner of my E body drilled a small hole in the clutch pedals arm and installed a short spring. The ends were straight to be custom bent.


RAT ROD AL said:
It has good bushings all lubed up on installation.

I will check to make sure I have the fork spring on correctly, now if I remove the over center spring and then that doesn't help, I understand that they are a :mad: to put back on if I need to.
Click to expand...

There a mutha to remove as well.
I’m staying tuned to this thread. I never had that problem unless it was a diaphragm pressure plate.

4spdragtop said:
Correct spring? Is /6 vs sb or bb the same spring?
Click to expand...
Now that is something I didn’t think of.
 
toolmanmike said:
Only if you change to a diaphragm pressure plate.
Click to expand...


Not true. The lever system has nothing to do with the over center spring and what it does.

I run a Ford finger B&B pressure plate and I can promise you I don't run anywhere near as much plate load as a diaphragm plate. Easily less than half of that.

It's all about how much spring pressure the plate has. That over center spring is there to help the driver push the clutch in.

The over center spring is not a return spring.
 
I have the small spring on the clutch fork to the Z bar to hold tension on the adjustable clutch rod. Is it supposed to go to bell housing to help pull it back. It's a pretty light spring.. I might have to get a heavier one to go to the bell housing.
 
Al while you are there under the car check gap between the clutch plate fingers and throw out bearing, it should be 5/32" this will give you the much needed one inch clutch pedal free play for your over center spring to operate correctly.
 
FWIW, The OC spring works in BOTH directions on my Barracuda. When everything with respect to pedal/clutch linkage is tight and adjusted correctly the B&B style 3 fingers push the the fork and linkage back to just past center on the OC spring. The spring then lifts the pedal to the stop and pulls any load off the release bearing. The linkage spring keeps the parts from flopping around.
In the other direction, the OC spring assists the release of plate pressure on the disc.

Check that the release bearing has the fork pads on correctly.
Try to determine weather or not the the release bearing contacts the three fingers at the same time. Just because it's new doesn't mean it's good. A finger out of adjustment will cause more pedal travel to release the disc.
Weaker springs on a new PP is another issue. A heavier linkage spring may help, but it's not "right".
 
the spring goes from the fork to a slot aside of the starter hidden behind the tin plate on the front of the bell. When I am in a bind and can't find the correct spring I use the spring from the park brake lever under the dash.

The only time you need to remove the over center spring on the peddle assembly is when you use a diaphragm pressure plate. Otherwise the peddle won't come off the floor on a shift until the RPM's come down. We just install a diaphragm clutch in a Demon and had that problem. The borg&beck three finger style was not strong enough . The customer blew the clutch in a week shifting a 7500

20171224_141707.jpg


20171208_234520.jpg


Picture 417.jpg


20171202_151400.jpg


20180421_200147.jpg


20180421_201431.jpg
 
Now Brewers has this kit. Rod is 7 1/2" .
Mine is not that long, it more like 6 1/2".
Would a longer rod bring the pedal up higher ?

MOPAR A833 4-SPEED TRANSMISSION & COMPONENT SPECIALISTS
Home » CLUTCH LINKAGE / FORKS » Clutch Adjuster Kits

buy.gif
checkout.gif

Product ID: AK448
AK448 CLUTCH ADJUSTER KIT, A/F-BODY SMALL BLOCK
AK448.jpg

Clutch adjuster kit for 1967-1976 A-body small block applications, also 1975-up F-body. Includes adjusting rod, nut, washer, grommet, spring, clip/washer. Adjusting rod is 7 1/2" overall length.
 
RAT ROD AL said:
Would a longer rod bring the pedal up higher ?
Click to expand...
It "could".
Is the current one out of adjustment threads but worked previously?
Longer will allow more adjust but will also decrease clearance between the release bearing and fingers. You don't want the bearing riding the fingers with the pedal up. Also if you adjust too much you can bottom the back sides of the fingers into the disc hub which could damage them.

The 0.060" would be a starting point.

upload_2020-1-8_20-7-33.png
 
Dave, I'm glad you brought this up. The rod on mine is around 6 1/2" long. I adjusted the nut to get the most length , took a test drive and the clutch started binding up when I pushed the pedal down. I jacked it up to check it out and like you said

"Also if you adjust too much you can bottom the back sides of the fingers into the disc hub which could damage them. "

So I backed it off some and now it shifts and disengages ok, just the pedal only comes up about 1/2 way and keeps the throw out bearing on the fingers. Pull the pedal up and there is about 3/8 - 1/2 " clearance there.
 
Have you checked the linkage for for abnormal motion? Worn torque shaft bushings, frame and bell studs, bent or worn fork pivot, or combinations of those can cause this scenario. It helps to have an assistant work the pedal travel while one watches for the motion. It should be tight throughout. Also look at the engine and trans mounts while your there.
 
You must log in or register to reply here.
-

Back
Top