Clutch pedal goes to floor
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- m37jarhead
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Clutch pedal goes to floor
Oh whoa-is-me. I reasembled the bell housting with new clutch disk, old pressure plate and new throw out bearing.
All were working fine before disassembly. Common sense said to replace the disk and the bearing while apart.
Engine and tranny re-installed in chassis. Cluth pedal goes to the floor. Inspection shows throw out bearing
properly in place and slides smoothly on the outer shell of the shaft that is around the splined shaft that goes to the crank.
No other adjustments were made to the linkage or the pedal since all worked fine before.
Springs on the clutch seem to be depressed without any pressure on the throw out bearing.
Only thing I can think of is I installed the clutch disk backwards. Your thoughts?
All were working fine before disassembly. Common sense said to replace the disk and the bearing while apart.
Engine and tranny re-installed in chassis. Cluth pedal goes to the floor. Inspection shows throw out bearing
properly in place and slides smoothly on the outer shell of the shaft that is around the splined shaft that goes to the crank.
No other adjustments were made to the linkage or the pedal since all worked fine before.
Springs on the clutch seem to be depressed without any pressure on the throw out bearing.
Only thing I can think of is I installed the clutch disk backwards. Your thoughts?
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Re: Clutch pedal goes to floor
Flipped disc is the first thought I had.
Good luck and let us know what you find.
Tim
Good luck and let us know what you find.
Tim
Happiness is enjoying what you already have!
Re: Clutch pedal goes to floor
I agree with Tim; get underneath and shine a light up into the disk/plate area while someone presses the clutch pedal-that should tell you a lot. I'd hate to pull the tranny again but you'll have no choice if the disk is flipped.
Gary
Gary
Cal_Gary
1954 M37 W/W
MVPA Correspondent #28500
G741.org Forum member since 2004
1954 M37 W/W
MVPA Correspondent #28500
G741.org Forum member since 2004
- m37jarhead
- SFC
- Posts: 647
- Joined: Sun Jan 06, 2008 6:55 pm
- Location: Apache Junction, AZ.
Re: Clutch pedal goes to floor
I've been under the truck to take a look. The clutch pedal, without the return spring attached, pretty much falls to the floorboard.
I can see the throw out bearing moving towards the "fingers" on the clutch as the pedal moved towards the floor. When the
throw out bearing finally engages the "fingers" on the clutch, there is no more room to further depress the clutch pedal.
Again, no changes or adjustments were made other than new throw out bearing and clutch disk.
No changes were made to the pedal or linkage because the unit worked fine before disassembly.
I can see the throw out bearing moving towards the "fingers" on the clutch as the pedal moved towards the floor. When the
throw out bearing finally engages the "fingers" on the clutch, there is no more room to further depress the clutch pedal.
Again, no changes or adjustments were made other than new throw out bearing and clutch disk.
No changes were made to the pedal or linkage because the unit worked fine before disassembly.
Member: Arizona Military Vehicle Collector's Club, Treasurer.
Past Pres
Member: MVPA #26600
Member: NRA
‘43 GPW, '53 M37 W/W, ‘54 M170 Field Ambulance,
59 M43, '76 M151A2, '86 CUCV,
'43 GPW, 416 & 101 trailers.
Past Pres
Member: MVPA #26600
Member: NRA
‘43 GPW, '53 M37 W/W, ‘54 M170 Field Ambulance,
59 M43, '76 M151A2, '86 CUCV,
'43 GPW, 416 & 101 trailers.
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- CPL
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Re: Clutch pedal goes to floor
Bad thing is, if the disc is put in backwards, once the center spring hub hits the flywheel studs and nuts without the friction surface touching the flywheel and then the pressure plate is tightened down forcing the friction surface to contact the flywheel, it usually bends the disc . 

Paul in Janesville, Wisconsin
1953 m37 parts truck
1961 m37b1 finally going together and turning green
and a bunch of other green trucks that are taking over my driveway
MVPA and MVPG member
1953 m37 parts truck
1961 m37b1 finally going together and turning green
and a bunch of other green trucks that are taking over my driveway
MVPA and MVPG member
- m37jarhead
- SFC
- Posts: 647
- Joined: Sun Jan 06, 2008 6:55 pm
- Location: Apache Junction, AZ.
Re: Clutch pedal goes to floor
Are the new disks typically marked, "front" or "back" or "engine" or "transmission"?
I didn't see any markings on the new disk.
I didn't see any markings on the new disk.
Member: Arizona Military Vehicle Collector's Club, Treasurer.
Past Pres
Member: MVPA #26600
Member: NRA
‘43 GPW, '53 M37 W/W, ‘54 M170 Field Ambulance,
59 M43, '76 M151A2, '86 CUCV,
'43 GPW, 416 & 101 trailers.
Past Pres
Member: MVPA #26600
Member: NRA
‘43 GPW, '53 M37 W/W, ‘54 M170 Field Ambulance,
59 M43, '76 M151A2, '86 CUCV,
'43 GPW, 416 & 101 trailers.
Re: Clutch pedal goes to floor
Not usually marked- the long side of the disk that accepts the transmission shaft should be pointing toward the transfer case.
Gary
Gary
Cal_Gary
1954 M37 W/W
MVPA Correspondent #28500
G741.org Forum member since 2004
1954 M37 W/W
MVPA Correspondent #28500
G741.org Forum member since 2004
Re: Clutch pedal goes to floor
We throught we had the same problem when we replaced the clutch in our 37. Turned out all we had to do was adjust the linkage...
Carl
53 Air Force M37 w/o/w
66 M101A1
53 Air Force M37 w/o/w
66 M101A1
- m37jarhead
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Re: Clutch pedal goes to floor
Thanks Gary:
At this point I don't see any other way to fix this problem other than remove the transmission, throw out bearing and pressure plate to see
which way the disk is oriented. I've not found a good picture of the disk being installed in any of the TM's that I have that shows how the
disk should be oriented.
Just to be clear, the flat side of the disk goes towards the engine? And the side of the disk with the "nub" goes towards the transmission?
At this point I don't see any other way to fix this problem other than remove the transmission, throw out bearing and pressure plate to see
which way the disk is oriented. I've not found a good picture of the disk being installed in any of the TM's that I have that shows how the
disk should be oriented.
Just to be clear, the flat side of the disk goes towards the engine? And the side of the disk with the "nub" goes towards the transmission?
Member: Arizona Military Vehicle Collector's Club, Treasurer.
Past Pres
Member: MVPA #26600
Member: NRA
‘43 GPW, '53 M37 W/W, ‘54 M170 Field Ambulance,
59 M43, '76 M151A2, '86 CUCV,
'43 GPW, 416 & 101 trailers.
Past Pres
Member: MVPA #26600
Member: NRA
‘43 GPW, '53 M37 W/W, ‘54 M170 Field Ambulance,
59 M43, '76 M151A2, '86 CUCV,
'43 GPW, 416 & 101 trailers.
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- CPL
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- Joined: Thu Jan 08, 2009 8:05 pm
- Location: South central Wisconsin
Re: Clutch pedal goes to floor
Yes, sounds like you have the right idea. The flatter side of the disc faces the flywheel and the raised part ( spring hub, splined coupler ) faces the transmission and pressure plate. If you look at the disc in a sideview you will see what side has more hub/coupling sticking out.
Paul in Janesville, Wisconsin
1953 m37 parts truck
1961 m37b1 finally going together and turning green
and a bunch of other green trucks that are taking over my driveway
MVPA and MVPG member
1953 m37 parts truck
1961 m37b1 finally going together and turning green
and a bunch of other green trucks that are taking over my driveway
MVPA and MVPG member
Re: Clutch pedal goes to floor
"The snout points out" is the best way I can describe it. I recall the short side that faces the flywheel being only 1/4 inch thick, while the longer side that points toward the tranny is an inch or more.
Gary
Gary
Cal_Gary
1954 M37 W/W
MVPA Correspondent #28500
G741.org Forum member since 2004
1954 M37 W/W
MVPA Correspondent #28500
G741.org Forum member since 2004
- m37jarhead
- SFC
- Posts: 647
- Joined: Sun Jan 06, 2008 6:55 pm
- Location: Apache Junction, AZ.
Re: Clutch pedal goes to floor
Thanks to everyone who contributed. I'll find out in a short time if the disk was installed incorrectly.
Will report back on the findings.
Will report back on the findings.
Member: Arizona Military Vehicle Collector's Club, Treasurer.
Past Pres
Member: MVPA #26600
Member: NRA
‘43 GPW, '53 M37 W/W, ‘54 M170 Field Ambulance,
59 M43, '76 M151A2, '86 CUCV,
'43 GPW, 416 & 101 trailers.
Past Pres
Member: MVPA #26600
Member: NRA
‘43 GPW, '53 M37 W/W, ‘54 M170 Field Ambulance,
59 M43, '76 M151A2, '86 CUCV,
'43 GPW, 416 & 101 trailers.
Re: Clutch pedal goes to floor
it still could just be adjustment. as the disk wears out he pedal gets higher and higher to engage because the pressurte plate has to be released further to engnage the thinning disk. so over the years it may have been adjusted to compensate for he thinning disk.I would try to eyeball and see if disk is in right then if it is you know it is adjustment. if disk is in backwards usually you will have a pedal that is difficult to push.
- m37jarhead
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Re: Clutch pedal goes to floor
Yesterday I crawled under the M and, as I rotated the engine, I started to back out the bolts holding
the pressure plate. Just a few turns at a time. After several rotations of the bolts, the pressure
plated moved off of the fly wheel surface about a 1/4 to 3/8 of an inch. At the same time the
fingers on the pressure plate were moving out towards the throw out bearing.
Now the clutch pedal and the throw out bearing only had to move slightly to engage the fingers
on the pressure plate. The clutch pedal travel was near normal. Looking throught the holes in the
pressure plate housing, it appears that the "fat" part of the hub on the clutch disk is facing
towards the transmission. Not enough room to see the front side of the disk.
Obviously I can't leave the bolts on the pressure place loose. When I re-tightened the the bolts
the problem of excessive pedal travel returned.
Any more thoughts on the above?
the pressure plate. Just a few turns at a time. After several rotations of the bolts, the pressure
plated moved off of the fly wheel surface about a 1/4 to 3/8 of an inch. At the same time the
fingers on the pressure plate were moving out towards the throw out bearing.
Now the clutch pedal and the throw out bearing only had to move slightly to engage the fingers
on the pressure plate. The clutch pedal travel was near normal. Looking throught the holes in the
pressure plate housing, it appears that the "fat" part of the hub on the clutch disk is facing
towards the transmission. Not enough room to see the front side of the disk.
Obviously I can't leave the bolts on the pressure place loose. When I re-tightened the the bolts
the problem of excessive pedal travel returned.
Any more thoughts on the above?
Member: Arizona Military Vehicle Collector's Club, Treasurer.
Past Pres
Member: MVPA #26600
Member: NRA
‘43 GPW, '53 M37 W/W, ‘54 M170 Field Ambulance,
59 M43, '76 M151A2, '86 CUCV,
'43 GPW, 416 & 101 trailers.
Past Pres
Member: MVPA #26600
Member: NRA
‘43 GPW, '53 M37 W/W, ‘54 M170 Field Ambulance,
59 M43, '76 M151A2, '86 CUCV,
'43 GPW, 416 & 101 trailers.
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- CPL
- Posts: 146
- Joined: Thu Jan 08, 2009 8:05 pm
- Location: South central Wisconsin
Re: Clutch pedal goes to floor
Just how thin was the old disc that you took out? If the rivets were about to touch and your freeplay was good before it could be adjustment time, it does not take much wear on the disc to move the fingers along way. Did you compare your old disc to the new one? Are all of the fingers on the pressure plate even? Did the disc move freely on the input of the transmission?Are there no issues with the linkage (sheared keys, bellcranks moved- I had this happen on my '55 Willys CJ-5 once the weld holding the bellcrank broke).
Just a few things that I would look for.
Just a few things that I would look for.
Paul in Janesville, Wisconsin
1953 m37 parts truck
1961 m37b1 finally going together and turning green
and a bunch of other green trucks that are taking over my driveway
MVPA and MVPG member
1953 m37 parts truck
1961 m37b1 finally going together and turning green
and a bunch of other green trucks that are taking over my driveway
MVPA and MVPG member