Clutch slave cylinder problems

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GM-TPI
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Clutch slave cylinder problems

Post by GM-TPI »

I decided to bleed my clutch system (since the fluid in my clutch master was black) and i ended up snaping the bleeding nipple off with the boss attatched :angry: I swear that was designed to fail...
The problem other than the obvious is that when i ordered the new slave it was the wrong one. (Knobs insist it's the right one) It's an Isuzu 5spd, car was manufactured december of 86. One of the things that are asked is if the pipe is in front of the resevoir..... :scratch: I'm assuming they're talking about the line coming from the master? in my case it is in front of the resevoir.
The bleed boss on the wrong slave i picked up is beefy (wont break off) but the bleed nipple on my old on is about 5/8" and the attaching boss is around 1/4" :cussing:
So i look up these parts online and there seems to be two types of slaves, one beefy..one not so beefy... the beefy one is suppost to be for 5spds pipe in front of res. and the not so beefy one for 4spds pipe in rear of res.
like i've said i've got a 5spd with pipe in front?? and it looks like the 4spd with pipe in rear slave will be the right one.. has anyone else had this problem??
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Series8217
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Post by Series8217 »

Huh?
The slave selection has absolutely nothing to do with where the pipe is on the master cylinder. The slave must match the transmission.
GM-TPI
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Post by GM-TPI »

Series8217 wrote:Huh?
The slave selection has absolutely nothing to do with where the pipe is on the master cylinder. The slave must match the transmission.
These are just what i am asked at the parts store, and online catelogs ask the same.
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Series8217
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Post by Series8217 »

I just looked on the catalog and the same part # is listed whether the line is in front or rear.
You should see two different slaves. One is for the 5-speed V6 car (the "beefy" looking one). The other is for the V6 4-speed and the 2.5L 5-speed (i.e. the Isuzu). The smaller bore one is what you want.
GM-TPI
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Post by GM-TPI »

Well i got the other slave cylinder and it was correct. This one is cast aluminum while the OE was cheap steel. So i installs it and flush the lines and now it seems my clutch master needs replacing. I'm absolutely sure there is no air in the lines and it still wont go into gear, hopefully it's not a defunk slave... :scratch:
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Post by Kohburn »

GM-TPI wrote:Well i got the other slave cylinder and it was correct. This one is cast aluminum while the OE was cheap steel. So i installs it and flush the lines and now it seems my clutch master needs replacing. I'm absolutely sure there is no air in the lines and it still wont go into gear, hopefully it's not a defunk slave... :scratch:
more likely you have one of the cheapo aftermarket cast iron ones - the welded OE ones are supirior - I think shaun went though 3 brand new aftermarket ones before finding a good one (may have been someone else)
GM-TPI
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Post by GM-TPI »

God i hope not, the thing with the OE steel ones is the bleeder valve is secured to the main body in an area around 1/8" and mine just snapped the whole bleed boss off...but i'm sure the valve has never been used since manufacturing of the car. I feel this isn't the end of my clutch problems :scratch:
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Post by Kohburn »

GM-TPI wrote:God i hope not, the thing with the OE steel ones is the bleeder valve is secured to the main body in an area around 1/8" and mine just snapped the whole bleed boss off...but i'm sure the valve has never been used since manufacturing of the car. I feel this isn't the end of my clutch problems :scratch:
i'd be tempted to have a machine shop bore and line the cast one with a nice stainless sleeve.. the cast ones tend to have a lot of inconsistency and surface holes in the bore that let air leak in


on a side note - if i ever have clutch trouble again I'm going to be real tempted to follow through with the cable replacement I designed for the fiero.
mastersativa
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Post by mastersativa »

i just replaced my slave with one from fiero store, mine was the cheap steel one and now i have a big beefy cast one on there. i have an 85 2.5 with the five spd isuzu. i also replaced the clutch pedal at the same time, i bled the system three different times, three different days, went through at least a gallon of fluid and my car still woudnt go into gear with the motor running. it seemed to be working fine and moved the clutch arm a mile but would not go into gear. i finally got the idea to put it in gear and then start it up, it worked. but now my clutch still doesnt seem to be disengaging all the way. so i ordered a new master cylinder. when i install that i hope the damn clutch will start working like it should, but like i said for some reason it wouldnt go into gear. was your car sitting for awhile? mine sat all winter and i was thinking the clutch was just sticcking to the flywheel a little.
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Post by Kohburn »

99.99 % of the time its air in the system - and 90% of that time its caused by the slave - including those new cheapo cast ones (and don't bother going to the dealer - they just repackaged the same thing you get at autozone or advance..
MNFatz
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Post by MNFatz »

If you've got everything bled out, it's time to start thinking about a collapsed pressure plate, damaged fork or throwout bearing.

I had a pressure place collapse on me. I don't know how to tell if this is the problem without pulling the transmission though.
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Post by Shaun41178(2) »

I bet its the slave. REbuild the slave and get some 600 grit sandpaper. Take the internals out as the seal is probably bad. Use the 600 grit to clean the inside of the slave bore. Wash it out thoroughly. Install the new parts and seal. The slave should work now.

I went through 4 aftermarket slaves before I said to hell with it. They are junk. Most likely the seal is bad. So replace the seal and you should be good to go. Replacing the master is probably not needed. They dont' go bad too often.
The Dark Side of Will
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Post by The Dark Side of Will »

Go with the fabbed steel slave. I got one from GMPD, I think. Are they still available?
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Post by Kohburn »

The Dark Side of Will wrote:Go with the fabbed steel slave. I got one from GMPD, I think. Are they still available?
don't believe so -

which is why I said to get the cast one bored and sleeved
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Post by The Dark Side of Will »

I guess it's been over two years, but I was able to get a steel one. Dammit my car's been off the road too long.
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