Go Back   The Ford Barn > General Discussion > Model A (1928-31)

Sponsored Links (Register now to hide all advertisements)

Reply
 
Thread Tools Display Modes
Old 05-23-2010, 06:15 PM   #1
SoCal_Alden
Member
 
SoCal_Alden's Avatar
 
Join Date: May 2010
Location: Carlsbad, CA
Posts: 66
Default Pressure Plate Fingers pushed in

I replaced the worn out clutch adjustment and trunion nut on my 29ccpo and adjusted the pedal freeplay according to Les' book ~ 1 inch. After getting everything buttoned up and back on the ground, started & warmed the engine - then pressed in the clutch and heard a noise (like a"boing"). The pedal went to the floor and now has no resistance. Shut everything down, removed the floorboards & clutch inspection plate. The throw-out bearing is not even close to the pressure plate fingers. It appears that the fingers are pushed in all the way and won't spring back. Here's my questions:
  • What could be the cause?
  • Is there a way to repair without removing the transmission and bellhousing?
Thanks,
Alden

Last edited by SoCal_Alden; 04-19-2011 at 10:53 PM.
SoCal_Alden is offline   Reply With Quote
Old 05-23-2010, 06:52 PM   #2
Tom Wesenberg
Senior Member
 
Tom Wesenberg's Avatar
 
Join Date: May 2010
Location: Mpls, MN
Posts: 27,481
Default Re: Pressure Plate Fingers pushed in

I've never heard of this happening, but it sure sounds like the pressure plate needs to come back out.
Tom Wesenberg is offline   Reply With Quote
Sponsored Links (Register now to hide all advertisements)
Old 05-23-2010, 07:38 PM   #3
MAG
Senior Member
 
MAG's Avatar
 
Join Date: May 2010
Location: Austin, Texas
Posts: 782
Default Re: Pressure Plate Fingers pushed in

I have had a couple of instances with those symtoms. One was a sheared pin in the throw-out fork. The other was the arm on the clutch release shaft broke across the pin. In both cases the throw-out arm would move freely ny hand. The first one required pulling the transmission to replace the pin.
If the fingers are truly stuck in, I agree with Tom, you are probably going to have to pull the clutch out. Bummer!!!!
MAG is offline   Reply With Quote
Old 05-23-2010, 07:59 PM   #4
SoCal_Alden
Member
 
SoCal_Alden's Avatar
 
Join Date: May 2010
Location: Carlsbad, CA
Posts: 66
Default Re: Pressure Plate Fingers pushed in

Thanks for your suggestions. Upon further inspection with a flashlight, I can see the throw out bearing move forward when I depress the clutch pedal however it doesn't come close to the pressure plate fingers. sigh, gues I'm in for a bit of research and then dismanteling.

BTW - Do any of you have any tips, techniques for pulling the rear end and removing the tranny & bellhousing?

thanks,
Alden
SoCal_Alden is offline   Reply With Quote
Old 05-23-2010, 08:58 PM   #5
Tom Wesenberg
Senior Member
 
Tom Wesenberg's Avatar
 
Join Date: May 2010
Location: Mpls, MN
Posts: 27,481
Default Re: Pressure Plate Fingers pushed in

Are the 6 pressure plate fingers even and about 5/8" below the pressure plate lip? That would be the rear most part of the pressure plate.
Tom Wesenberg is offline   Reply With Quote
Old 05-24-2010, 12:25 PM   #6
SoCal_Alden
Member
 
SoCal_Alden's Avatar
 
Join Date: May 2010
Location: Carlsbad, CA
Posts: 66
Default Re: Pressure Plate Fingers pushed in

Thanks for suggestions and support. I checked the 6 pressure plate fingers this AM and they all appear to be even and about an inch and a half in from the rear face of the pressure plate.
SoCal_Alden is offline   Reply With Quote
Old 05-24-2010, 12:29 PM   #7
SoCal_Alden
Member
 
SoCal_Alden's Avatar
 
Join Date: May 2010
Location: Carlsbad, CA
Posts: 66
Default Re: Pressure Plate Fingers pushed in

Here are a couple of pics - my first attempt at posting photos.

Alden
Attached Images
File Type: jpg 016.jpg (48.6 KB, 150 views)
File Type: jpg 017.jpg (44.0 KB, 138 views)
SoCal_Alden is offline   Reply With Quote
Old 05-24-2010, 01:00 PM   #8
2manycars
Senior Member
 
2manycars's Avatar
 
Join Date: May 2010
Location: Eastern CT
Posts: 2,725
Default Re: Pressure Plate Fingers pushed in

While looking through the inspection hole, watch the throwout bearing movement as you run the clutch pedal from all the way up to as far down as it goes. If the pedal moves a lot more than the bearing, then the previously mentioned linkage failure is most likely. The throwout arm on the outside of the bell housing is easy to inspect, and may have broken. My brother had that happen. If that arm is ok, and when you run the pedal from up to down, the arm, shaft and linkage move as they are supposed to, then the likely cause is the pin that fixes the throwout bearing collar arm to the shaft. That will require removing the transmission and bell housing. Inspect all this stuff before you pull the transmission out.
2manycars is offline   Reply With Quote
Old 05-24-2010, 01:18 PM   #9
SoCal_Alden
Member
 
SoCal_Alden's Avatar
 
Join Date: May 2010
Location: Carlsbad, CA
Posts: 66
Default Re: Pressure Plate Fingers pushed in

Thanks for your suggestions - The clutch pedal does actuate the throw out bearing and the collar slides well on the shaft. The bearing just doesn't engage with the pressure plate fingers - missing by an inch or so.

It is becomming evident that the only way I'll get to the bottom of this is to bite the bullet and disassemble everything and install a new/rebuilt pressure plate and clutch disk - including the pilot and throw out bearings just for good measure.
SoCal_Alden is offline   Reply With Quote
Old 05-24-2010, 02:17 PM   #10
JoeWay
Senior Member
 
JoeWay's Avatar
 
Join Date: May 2010
Location: Quincy CA
Posts: 749
Default Re: Pressure Plate Fingers pushed in

I don't have an original pressure plate here to look at, so I could be way off. I'm just trying to imagine a scenario that would result in your problem.

It sounds to me as if the fingers have gone over-center. You said you replaced a worn-out trunnion. Could a previous owner have adjusted the pressure plate fingers trying to compensate for the worn trunnion and not knowing how it is supposed to be adjusted? If the adjuster bolts were run way out, then you replaced the trunnion and set the correct pedal free play, the throwout bearing would depress the fingers way beyond the normal range. If the mechanism allows for the fingers to go over-center, your condition would result.

If this is the case, you might be able to recover by prying the fingers back past center one at a time, then adjusting the fingers as has been described here in the past.

Maybe Tom W. or others who are more familiar with the original pressure plate can comment as to whether the fingers can go over-center if depressed to far.

Joe
__________________
1929 Tudor
since 1962
Feather River A's
JoeWay is offline   Reply With Quote
Old 05-24-2010, 02:44 PM   #11
SoCal_Alden
Member
 
SoCal_Alden's Avatar
 
Join Date: May 2010
Location: Carlsbad, CA
Posts: 66
Default Re: Pressure Plate Fingers pushed in

Thanks for the advice Joe - That sounds like what has happened. Your suggestion to try and pry them back one at a time might be worth a first try - before I rip everything apart.
SoCal_Alden is offline   Reply With Quote
Old 05-24-2010, 03:31 PM   #12
lfg
Member
 
lfg's Avatar
 
Join Date: May 2010
Location: Arizona
Posts: 50
Default Re: Pressure Plate Fingers pushed in

I had the same thing happen to me when I installed a rebuilt engine with a new clutch. After installation, but before I connected the clutch linkage, I pushed the clutch pedal down (it went too far because I had not connected thge linkage) and fingers went all the way down and would not return. Sounds like this is where you are.

I removed the engine and loosened the bolts on the clutch retainer. The clutch then returned to its normal position. I am now very careful to always have the linkage adjusted on a new installation before I push down on the clutch pedal so I can't push it in too far.

I'm sure you don't want to hear about removing the engine but I couldn't get it to release any other way.
lfg is offline   Reply With Quote
Old 05-24-2010, 08:55 PM   #13
Doug Linden
Senior Member
 
Doug Linden's Avatar
 
Join Date: May 2010
Location: Massachusetts
Posts: 130
Default Re: Pressure Plate Fingers pushed in

It sounds like you popped a spring in either the pressure plate or the clutch disc and it's jamed the PP in the fully released position.
Doug Linden is offline   Reply With Quote
Old 04-19-2011, 04:05 PM   #14
V4F
Senior Member
 
V4F's Avatar
 
Join Date: May 2010
Location: ca.
Posts: 2,510
Default Re: Pressure Plate Fingers pushed in

i would get help so they can turn the motor while your looking for the problem . pull all the plugs so it will turn ez . with the inspection covers off , spiun the motor by hand & listen for something rubbing . i would try a pry bar or screw driver to see if i could pop the arms up . good luck ............. steve
__________________
V4f
V4F is offline   Reply With Quote
Old 04-19-2011, 05:59 PM   #15
82ndscotty
Member
 
Join Date: May 2010
Posts: 35
Default Re: Pressure Plate Fingers pushed in

Alden, A quick check in high gear one rear wheel off the ground can you rotate the wheel?Scotty
82ndscotty is offline   Reply With Quote
Old 04-19-2011, 10:42 PM   #16
SoCal_Alden
Member
 
SoCal_Alden's Avatar
 
Join Date: May 2010
Location: Carlsbad, CA
Posts: 66
Thumbs up Re: Pressure Plate Fingers pushed in

Problem solved - I ended up pulling the trans and sending it out for rebuilding. Bought a new pressure plate and clutch disk along with the throw out bearing and of course U-joint. Replaced the rear engine mounts and after getting all the parts back together was amazed at how nice the tranny shifted and also how quiet it is now.

A lot of work but now have the running gear in top shape.

This weeks chore is to remove the head - smelled exhaust gas in the radiator - the head hasn't been off in who knows how many years.

Have our technical Director from the Palomar A's coming over this Friday with a hoist to help pull the stubborn thing off the block.

Thanks for everyones helpful suggestions. I tried each and every one until I finally fixed it the hard way - but bery pleased with the end result!

cheers,
Alden
SoCal_Alden is offline   Reply With Quote
Old 04-20-2011, 11:15 AM   #17
SoCal_Alden
Member
 
SoCal_Alden's Avatar
 
Join Date: May 2010
Location: Carlsbad, CA
Posts: 66
Smile Re: Pressure Plate Fingers pushed in

The actual problem was an old pressure plate with weak springs - after removing the trans I re-adjusted the fingers per spec and tried the clutch by hand - the springs were easy to depress.

After replacing the parts I now have a firm clutch pedal.

Thanks for asking what the root cause was.

Alden
SoCal_Alden is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Sponsored Links (Register now to hide all advertisements)


All times are GMT -5. The time now is 02:12 AM.