Slave cylinder problems

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iamtherealJayy

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No, as far as I can tell the neutral safety has been cut and wired together because I do not have to press the clutch to start the truck. Which is a good thing in my opinion lol I’ve had to start the truck in gear a few times because the slave/master went out all of a sudden. I have a cheapo vacuum bleeder but I haven’t tried it with the clutch because it’s always been such a pain to bleed and I don’t want to introduce air into the system. The first time I changed the slave I had to end up unbolting it then bolt it back on because it just wouldn’t build enough pressure to extend the slave arm. It was pushing clean solid fluid but had no movement in the slave. I undid the two nuts and it popped right out topped fluid off and bolted it back on and it worked fine for a while then the one time I pull a trailer I go to put the truck in reverse and my master cylinder goes out and can’t go into any gears and the shaft to pedal is wet.
Edit: I thought about doing the bottle of brake fluid with a hose ran into it method of bleeding the brakes but I don’t know how it would work for the clutch.
 

SquareRoot

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I don't care for Vacuum bleeding systems either. That's why I bought this one, it pushes fluid thru the system in reverse. You simply snap that black funnel looking thing on a bottle of brake fluid and the hose pulls the fluid from the bottle and gets pumped thru the line and into the bleeder screw (which should be open). Fluid fills the slave (or caliper) first and then pushes the air out the lines up thru the master cylinder reservoir until its full. There's NO chance for air to enter the system anywhere. Close the bleeder, remove hose. Boom done!

Copy on the safety switch. Initially, I put a new on in but its self adjusting which is a problem. It sets to whatever maximum position the pedal gets depressed. If you push the pedal to the floor ONE time that's where it sets and then you have to push it to the floor every time after that to start the truck. And like I said, that over extends my diaphragm so I took the switch out.
 

iamtherealJayy

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I don’t see a visible link to what you’re talking about lol that’s why I assumed it was a vacuum bleeder. What you’re talking about tho sounds a hell of a lot easier. Could you try and send it again or tell me what it’s called so I can look into it?
Edit: nevermind the attachment is visible now.
 

Grit dog

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Couple things...
1. From your description, it sounds like nothing is wrong. The 1st and Reverse thing sounds like typical behavior of an old trans with non syncro 1 & R gears. Sounds identical to my old Jeep.
2. IMO pedal position for clutch engagement is more personal preference than performance issue. I prefer clutch engagement to happen in the first half of the pedal travel, so you don't have to mash the clutch to the floor every shift.
3. If it's engaging and disengaging properly, it "shouldn't" need to be bled?
4. Is either the MC or the slave rod adjustable? I'm not familiar with these clutch systems. That can/will adjust your pedal height for engagement.
5. If I'm missing something, it may still need to be bled.
 

iamtherealJayy

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Alright so as some of you know I’ve been driving the 78 k10 for past couple weeks. Today was the first time driving the 87 since June 8th, and this clutch being hydraulic I knew would feel different than the mechanical clutch but the pedal goes pretty much straight to the floor and doesn’t grab until the top of pedal. Made an interesting drive pulling a trailer. Usually the pedal is fairly stiff and grabs as soon as you let off(my preference is grab as soon as you start letting off) but today I kept revving up and it would all of a sudden grab. Honestly sucked. I’ve replaced this slave cylinder twice, master once, the line between them once. I’ve only had the truck since 8/30/20. Seems something has a problem somewhere for how much I’m having problems with this hydraulic system.
 

WP29P4A

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What quality/price level of parts (slave cylinder) are you buying? I learned my lesson years ago, the lowest price (rebuilt) parts are temporary if they work at all. Even the most expensive high quality (allegedly) parts are not always reliable these days.

If I plan to keep the vehicle for more than 4 weeks after I replace the part, I buy the best quality parts available, because I don't have the patience to keep swapping out the same low quality parts on a regular basis.
 

iamtherealJayy

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I don’t remember exact brand it was from oreillys they were all new not reman. And the line between the master and slave was from lmc truck. I’ve had so much trouble out of bleeding this slave and keeping it bled.
 

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