(FIXED) Canter FG649 (2003) clutch pedal is free

[Bris31]

This morning after a week of truck sitting idle, started the truck and found clutch pedal is free i.e. it goes to floor freely and doesn't return.
Did some basic troubleshooting:-
Found no oil leakage anywhere - inside cabin or on ground below.
Brake oil level is same as before this problem and brake pedal resistance is as normal.
Checked under the truck for Clutch direct power cylinder movement - no response when clutch pedal is pressed (or bring back manually).

I suspect clutch master cylinder is the issue, needs to be taken out and to mechanic for repair (if) or replace with new one.

But wanted to know if there is something else I can check before taking it out.

Also I removed the lower dashboard under steering and can see clutch master cylinder above clutch pedal, it is very tight place to reach to take it out. Is there a trick to remove it (like removing the nuts, oil pipe etc).

Thanks in advance.

 

[Aussie Iron]

Sounds to me that the "rubber" seals (probably not rubber any more) are buggered in the master cylinder. So, Yes it will need to be removed and have a new seal kit fitted. Hard to get too, Yes somewhat. I've taken them out without removing the dash gauges and taken the dash out (maybe slightly easier) but more to remove.
Not hard to rebuild yourself if you get a kit. Watch how you are pulling it apart (direction of cup lips) and reassemble the same way. You can wash the old cylinder out with just water as it will remove brake fluid. Just make sure you dry it off well and apply a bit of rubber grease ( sometimes I just use a little brake fluid if reassembling straight away) to new rubbers and cylinder walls etc.
It can be a problem to bleed at times because sometimes it gets an air lock in the line that supplies brake fluid to the cylinder. If I have my gear at home I reverse bleed it from the slave cylinder till the master cylinder is full.

Dan.

 

[Bris31]

Dan, thanks for quick reply and tip about removing the air lock.

Would it be much easier to change the CLUTCH MASTER CYLINDER ASSY, than repairing the rubber seal? The whole thing cost only $116 at Brett.

Also I was thinking before removing the master cylinder, I remove the clevis pin from clutch pedal and check the movement of the rod - in/out, but not sure what to expect there though.

 

[SkiFreak]

Also I was thinking before removing the master cylinder, I remove the clevis pin from clutch pedal and check the movement of the rod - in/out

You could do the same thing by moving the clutch peddle with your hand.
As to which is simpler, repairing or replacing... I guess that comes down to your skill levels and how confident/comfortable you are working with mechanical components.

 

[Bris31]

Great, I could check master cylinder rod moving when clutch pedal is pressed - without removing master cylinder.
So looks like seal is at fault as Dan mentioned.
Will get a new master cylinder to replace.

 

[Bris31]

Sounds to me that the "rubber" seals (probably not rubber any more) are buggered in the master cylinder.

Dan.

Just a thought, if rubber seal is buggered, shouldn't be oil would be leaking out all over?

 

[seangrips]

If you go new, you’ll at least no it’s history.
while your doing it replace the slave cylinder as well.
My big tip
Allow a lot of time to do the master. It’s cuddly and wasn’t design for big hands
Match your rod length before installing, that’s hard to adjust after the install

 

[Bris31]

New master cylinder coming next week.
Yes, I intend to have same old measurements of push rod length etc on the new master.
Maybe cutting a small window on the front panel will help with installation for my big hands?
It looks so simple but needs lots of patience and reach. Wonder how do they install in factory.

 

[SkiFreak]

Wonder how do they install in factory.

The peddle assembly would be installed prior to installing the dash.

 

[Aussie Iron]

Just a thought, if rubber seal is buggered, shouldn't be oil would be leaking out all over?

Not necessarily as there is a rubber to stop leaks and a rubber to make it all work.

Dan.

 

[benttofly]

my fg439 did the dsame thing. clutch froze to flywheel. big mess big expense. i am with the above poster if the seal went you should have a big puddle just to the left of the steering column. and your resivior would be empty. i had my master go out. it didnt just pushi in an stay loose. also had nice puddle. it still functioned but squirted up my shoe. 115 bucks at the dealer and an hour cutting up the knuckles, a quick two person vacuum assisted bleed job all around and back on the road ( 2 months after clutch freeze) best of luck

 

[Bris31]

FIXED (fingers crossed):

After a tip from a panel beater- opened 2 main bolts to the bracket and removed the in/out pipe. Then loosened the 'push rod' with a pliers jammed on the grooves which are just behind the locknut (it found to be too tight). I was told these grooves are meant for this purpose. Turned the whole cylinder unit anti-clockwise to remove the 'Push Rod' from the U Bracket. Left the U bracket as it was - all in 10 min or so.

New cylinder unit went in same way which didn't have those grooves on the push rod but managed to tightened the nut. Did the reverse bleeding from slave cylinder (as Dan suggested above), adjusted the clutch pedal height so it engages the gears smoothly when depressed. Had a good drive around the block. Took about an hr for 2 persons.

Will have another longer run later to make sure all good.

Cheers

-

 

[SkiFreak]

Good to hear that you sorted it out.