T-Series loss of clutch after tranny install

[19_again]

I just installed a rebuilt tranny from Quantum, I followed the Bentley steps all through the process, removing the engine and old unit and reinstalling the new assembly. Today I filled the tranny with fluid and when I tried going through the gears for the first time I had no clutch pressure. I pressed the pedal down a few times and got complete resistance at the top of the stroke, seemed more like a mechanical stop than the normal pressure you feel from good pressure when pressing the brakes. Upon feeling this unusual pressure I checked the system and found I hadn't completely set the slave boot in place. I took care of that, checked the local nuts and bolts while I was under there and tried the pedal again. This time it went straight to the floor every time, no resistance. Plenty of fluid in master, didn't touch the master during the work. I'm surprised there wasn't a gasket at slave connection as there was a drop of fluid on the low point of the slave. Any suggestions?
Mike

 

[bob67bgt]

If i was just doing a trans swap i would not break the hydraulic system. Just remove the slave from the trans and use a thin wire or zip tie to keep the slave piston from coming out of its bore. If you pulled the slave from its line then be sure the system has no air in it. If you blow the piston out of the slave when bleeding then you have a bad flex line or forgot to install the release bearing. There should be a copper washer between the flex line and the slave cyl. Without more details thats all i can think of. Bob

 

[19_again]

Thanks Bob, I'll be out of town for a few days but will check it when I return. There was literally no resistance when applying pressure.
Mike

 

[19_again]

Upon a quick inspection on the way home today I found that half the fluid is gone, but it must have been gradual. As we have absorbent granules on the floor with oil from the engine removal and water from heater disconnect etc there could easily be the rest of the fluid there as well. Easy fix, I was concerned that there was no leak and still no pressure.

 

[19_again]

Turns out the fluid was leaking out of the slave bellows, they are ok, but the interior seals must be gone so I've ordered a repair kit.

 

[DrEntropy]

Sat too long... be sure to run a brake hone thru it a few times before ya put th' new puck in there.

OH! and you *could* find a proper sized puck at NAPA in a pinch.

 

[19_again]

it only sat over the winter, and was unhooked for the four weeks since we started the engine/tranny work. but as if every component they always work right up to the moment when they don't.
Are you saying to run the brake hone through the inner passages of the cylinder? Never done this before.

 

[DrEntropy]

Like honing a cylinder in the engine... 45* cross-hatch (slow speed on a hand drill, moving in and out). A "brake hone" from NAPA... AMCO.

 

[Nunyas]

it only sat over the winter, and was unhooked for the four weeks since we started the engine/tranny work. but as if every component they always work right up to the moment when they don't.
Are you saying to run the brake hone through the inner passages of the cylinder? Never done this before.

Could have been those couple of weeks sitting without fluid in it. The materials they like to make these parts out of like to shrivel and get brittle without constant fluid wicking them to keep them soft and supple...

 

[DrEntropy]

As well as exposed to atmosphere. It needs rebuilding. With the hone treatment as an ameliorator.

 

[Nunyas]

thar you go again usin' them big werds on me... whar's my dicshunairy?!

 

[RonMacPherson]

AND, especially for someone not using a hone before, make sure the cylinder is well lubricated, i.e. brake fluid, etc... during honing...

 

[19_again]

Thanks Ron, I would not have thought of that. I'm guessing that once I've got this thing apart, it will be pretty obvious what needs to be honed. I went hone shopping yesterday only to find there were three sizes, I got the smallest, something in the order of 31/64" to 2", I didn't think a larger one would be necessary. The ameliorating notwithstanding, I'm hoping to avoid excessive aspiration in addition to rampant anti-disestablishmentarianism.

 

[DrEntropy]

Or you could use Marvel Mystery Oil in lieu of brake fluid... Just be sure to rinse all with mineral spirits and then something like lacquer thinner. Air compressor dry and wipe with soft cotton cloth after. Winding a piece of old T-shirt around a chopstick works WELL.

Ron may beat me up later, at his convenience. :wink:

 

[RonMacPherson]

MMO would work well. I use brakeclean to spray though the components after honing. Agree with Doc on air blow. But make sure you use a CLEAN cloth to wipe off, hopefully lint free. Then a rinse coat of brakefluid internally before assembly.

 

[MGZT260]

One thing to remember. Organic brake/clutch fluid is an excellent paint remover.

 

[19_again]

yupyup, I hate handling the stuff near the vehicle. I keep the old bottle so that I can pour small amounts at a time. Learned the hard way not to try and pour from a can or bottle that was near full.