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Discussion Starter #1
recently i had a situation where the clutch engaged the gears when the pedal was very close to the floor. it reached a point where i could not get it into reverse or 1st without grinding...so i thought i might have air in the line. i went to bleed the slave, and when it was open, no fluid would come out, despite having it open for over an hour.

i replaced the slave and the flexible hose attached to it, and when i unscrewed the metal hose at the union, even then i did not have any fluid leak out (the reservoir had sufficient fluid). even if i pushed on the clutch (i know this would get air in the system), nothing happened...and no fluid leak.

i'm wondering if there's a blockage in the metal line, or if the master is bad. i removed the fluid from the reservoir, but have not removed it from the master yet.

the piston on the master looks fine, and no issues with shearing - it all activates upon pressing the clutch pedal.

welcome any thoughts.

at this point, i'm thinking just replace the master clutch cylinder, and have an entire new set of components...but if the issue is a clogged line, i'd like to get that figured out first.

Thanks.
 

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Richard Jemison
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Clutch

Shorten the rod between the MC and clutch leaver. The piston assembly must return (outward/to the rear) until there is a minute amount of play between the piston and the rod.

Can`t get any? Rod is too long.
 

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Discussion Starter #3
Thanks for the post. I will have to check to see if there's any play between when i start to press the clutch and when the are that moves the piston starts to move to the front of the car. to shorten the rod, it looks like i want to turn the bolt so that it moves closer to the firewall (back of the car). there is a small gap between the arm where the piston connects and the firewall...so it's not hitting the firewall to restrict movement. I also seem to recall there is a specific length that the piston should be from the that arm and where the master cylinder is mounted. Do i understand your suggestion correctly? move that bolt closer to the firewall, to shorten the rod?
 

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Discussion Starter #5
thanks. in order to shorten the rod, i assume i need to move the bolt closest to the robber boot towards the rear of the car. that should pull the fork forward, shortening the rod. correct?
 

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If you the rod measures what it should, or very close, then its not likely to be your problem.
The nut closest to the boot is the jam nut.
Loosen it, then turn the threaded rod assembly inward, then re-tighten the jam nut.
 

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It sure sounds like the piston in the master cylinder is not retracting enough - as Alfar7 suggested.
 

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Discussion Starter #8
the rod appears too long. I had a mechanic 'adjust the clutch' a couple months ago, and i think he played with the length of the rod. i'm going to see if i can shorten it closer to the target length. i assume the cotter pin has to come out to get the fork to move on the screw/post closer to the front of the car to shorten it. as it is now, the fork almost touches the firewall.
 

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Discussion Starter #9
update: i've removed the metal hose that goes down to the slave cylinder, and concluded it does not have a clog. i shortened the rod that attaches to the piston arm, and with fluid in the reservoir, tried to bench bleed the clutch master cylinder. no fluid came out. I did hold my finger over the 'out' port of the mast upon retraction of the rod, and heard air flow out when i pushed the rod in. the reservoir fluid was quite dirty when i started this process (and siphoned it out before starting this process). i'm wondering if i just have a clog at the reservoir. i do have a new master cylinder here, but am trying to figure out how to get the bolts loose to remove it given the tight quarters.

suggestions welcomed. Thanks!
 

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Hmmm, yes, I once experienced a blockage of the bleed port. Remove the bleed nipple and check that that one is clear too. Don't use anything which might scratch the seat.
 

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Discussion Starter #11
update - i was able to get the clutch master out, so now it' just putting all the connections back together and bleeding the line. thanks for the help. i may be back if i have issues after bleeding the line. Thanks everyone.
 

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The Factory Spec For The Clutch Master Cylinder Rod Length Is 134 mm (measured from the cylinder mounting flange to the outer edge of the clevis pin). When Installed Correctly The Clutch Pedal & Brake Pedal Are Approximately Level With Each Other (clutch usually a bit lower). Rotate The "threaded fork" In Or Out On The Rod To Achieve The Correct Length.

-John
 

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134 mm is a good place to start but bare in mind that a non OEM cylinder may not be exactly the same as an Ate.
 

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Discussion Starter #14
Question - perhaps for you John.
should the clutch pedal be almost level with the brake while the clutch master is 'unpressurized'...meaning that i don't have the lines connected down from master through the slave cylinder yet. it currently hangs about 1/4 of the way down...and i thought that with pressure from the lines being full of fluid, it might raise up a bit.

the master is installed but the "system" does not have fluid, nor have i bled it of air.
 

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the rod appears too long. I had a mechanic 'adjust the clutch' a couple months ago, and i think he played with the length of the rod. i'm going to see if i can shorten it closer to the target length. i assume the cotter pin has to come out to get the fork to move on the screw/post closer to the front of the car to shorten it. as it is now, the fork almost touches the firewall.
Why did you have the clutch adjusted ? What was the symptoms ? I'm asking because I'm wondering if the original problem couldn't be the clutch pedal pivot. It could give the illusion that the clutch master cylinder rod need to be adjusted.

The pivot hypothesis doesn't explain the fluid that doesn't follow the gravity law though !
 

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Question - perhaps for you John.
should the clutch pedal be almost level with the brake while the clutch master is 'unpressurized'...meaning that i don't have the lines connected down from master through the slave cylinder yet. it currently hangs about 1/4 of the way down...and i thought that with pressure from the lines being full of fluid, it might raise up a bit.

the master is installed but the "system" does not have fluid, nor have i bled it of air.
There Is A Spring In The Clutch Master Cylinder Pushing The Rod Outwards So It Shouldn't Matter Whether There Is Fluid In The Cylinder Or Not For Pedal Position. The Location Of The Clutch Pedal To The Brake Pedal Is A Quick Way To Determine If The Clutch Rod Length Is In The Ballpark. If As You Say The Rod & Pivot Arm Are Almost Touching The firewall Then The Clutch Pedal Should Be At It's Highest Position. You Also Say That It's 1/4 Of The Way Down From The Brake Pedal Position. Those Two Don't Go Together So Something Is Wrong. Like Another Poster Stated Maybe The Pivot Arm Is Failing (weld breaking)? Did The Mechanic Who Worked On The Car Extend The Rod Length As Far As Possible In Order To Raise The Clutch Pedal Height? This Points To A Failing Pivot Arm To Me As Well.

-John
 

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Discussion Starter #17
the clutch was engaging very close to the floor (clutch pedal hangs from the top). after he adjusted it, it engaged higher and 'seemed' more like where it should engage. I am wondering if i really was dealing with a loss of fluid in the line, and it gave me a false impression at the time. I'm hopeful that the new slave and master will address the point at which the clutch engages the gears. - i can probably check with the mechanic to see what he did, but i think he adjusted the rod. he was not an alfa mechanic, so he may not have known about the ideal length of the rod.

when the line is full, and properly bled, will the clutch rise a little? i may need to check the length of the rod one more time before i bleed the line. getting the pin out of the pivot arm, and getting to the fork so i can adjust it out a little is a tedious process - i'd hate to do it more than once :)
 

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Discussion Starter #18
i just saw Dellta's post - so i'm going to adjust the fork a bit to extend, but not as far as previously, and keep it close to the recommended length....fill up the lines and see what happens. before i disconnected the hoses, the pedal did return to full height after being depressed. maybe that does not indicate that the pivot arm is ok, but i would have assumed that the pivot arm would not allow the clutch pedal to return to the top after being depressed. sounds like i need to do some more adjusting, and then trial and error - and perhaps have to deal with the dreaded pivot arm replacement. based on other forum member comments, this sounds like it is a major pain - thanks for all the comments guys. I really appreciate it.
 

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Discussion Starter #19
one last thought - before i replaced the master, the pivot arm was almost touching the firewall, and the clutch pedal was just about as high as the brake. now that i have the new master, and the rod is very close to the suggested length, the clutch is about 1/4 of the way down from the break (p.s...not a scientific measurement of distance). i agree my comments appeared to contradict each other - but one was before the master replacement and one was after. thanks.
 

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Discussion Starter #20
Slave and master replaced. Clutch pedal below brake

I have replaced the master and slave cylinders on the clutch . The rod length is 134mm and it is pushing fluid through as I was able to bleed the line. The travel distance for the slave piston is about 7-8mm. When I attempt to get into reverse, there is grinding so I have not forced it. The clutch pedal is about 2 inches below the brake pedal. When I depress the clutch, the rod on the master responds immediately. When I try to pull the clutch pedal up, there is no movement....it is at its highest allowable point in its current position.

A couple questions. Given these symptoms, does it still point to the pivot arm in the pedal box as the issue. Is it more likely I need a new clutch. I would prefer to avoid the challenge of replacing the clutch pivot arm if that is not likely the issue. If it is the clutch I expect it will need to be towed to get it repaired.

Thanks for any input.
 
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