Engine/Transmission (1998.5 - 2002) Not a 911, but truck dead. clutch issue in Master/Slave cylinder???

[TomGolden]

Hi all,



My truck took a dump on me this weekend. I believe it is in the clutch master cylinder, but I may be mistaken. I am hoping some of you can point me in the right direction. I am going to have to take it into a good local shop, but I wanted an idea if possible as to what the problem likely is.



Symptoms:

Pulled into grocery store parking lot. Went to take it out of gear, clutch pedal went to floor and stayed there. No return. Clutch did not disengage, had to turn off motor to get truck to stop.



I drove it home, but it wasn't fun. Had to shut off engine, put it in 1st gear, crank engine while in 1st gear, then could shift w/o using clutch pedal up and down the gears just fine.



Got home, did visual inspection. No great leaks in hydraulic system, master cylinder reservoir was about 1/2 full, so I filled it up. I pushed clutch pedal by hand. Pedal has about 1/2 normal pressure going down, as soon as pedal is all the way down, you head swoooosh sound (sounding like all the fluid evacuating the m/c) then pedal looses all pressure, and very limply and slowly returns to normal up position. But even when you depress the pedal, the clutch never disengages.



Now I crawled under the dash because I thought maybe there was a return spring that had just broken or something... Well, didn't see one, but I did notice hydraulic fluid has been leaking a little out of what appears to be the master cylinder portion that just comes through the firewall into the cab, and there is a plastic piece about 1" diameter and 2" long that somehow fastens into this part of the m/c and goes around the shaft of the piston. That piece is loose and completely free from the m/c and slides along the piston shaft freely. I'm thinking that is hopefully my problem... ...



Can anyone shed any light on this for me? Would greatly appreciate it.



Thanks,

Tom

 

[Gary - K7GLD]

YUP - sounds like you are a candidate for a new master/slave cylinder transplant! And I don't think I'd screw around with a patchwork fix - as I understand it DC sell the whole setup as an assembly - and if one part of the current setup is bad, the rest might not be far behind...



Good luck!

 

[Steve St.Laurent]

That piece should be loose to move on the shaft. That is the clutch safety switch. There is usually a small foam pad between it and the master cylinder and when I've had master cylinders go out that pad has been wet with hydraulic fluid. Call South Bend Clutch - they have individual replacements.

 

[Big P]

Does anybody know if Southbend is selling an adjustable master/slave assembly now?

 

[GMincher]

Don't know about the South Bend but I just replaced mine recently. The DC unit comes complete with fluid and is a 20 minute bolt in. It also cost me $250!!, and no one in Md. had one in stock!! Didn't these parts used to be made out of cast iron, with replaceable seals that cost about a buck each? Is my age starting to show? If South Bend makes a repairable, rebuildable unit, even if the truck is off the road for a couple of days, buy it!!

 

[NIsaacs]

Dead Master Cylinder

Like GMincher said, Dodge sells the complete unit, Master, Slave, Reservoir, and lines. It is full of fluid so you don't have to bleed the system. I have heard this can be tough. The line is two piece, with a hydraulic fitting on each line. They just pop together with no loss of fluid or air contamination. The unit from Dodge on my O1,was 200. 00, Napa wanted the same money, but would sell them seperately. Since I had to order the parts,(neither store had them), I got the Dodge one. The original line is one piece with roll pin holding it on each end. I didn't disconect the line, just threaded the slave cylinder up through all the junk in the way.





"IF IT AIN'T CUMMINS POWERED, IT AIN'T A TRUCK"





"NICK"

 

[TomGolden]

Just an update:



It was the diaphragm inside the master cylinder allright. My mechanic replaced the beast and all is well. They did just the M/C and so had to bleed the system, which he grumbled took a long time :-{}



Anyway, Godzilla is breathing fire and smoke once again.