86 K20 Curb drop = temporary Clutch No Engage

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viaminveniam1939

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86 K20 350M (L,1,2,3,R) 4x4

Just installed new clutch master & slave cylinders. I bled the system & am fairly certain I got all the air out. NOTE -I did NOT bench bleed the master. I first went about bleeding the system the old fashioned way… this obviously took a while. So long, in fact, having never bled anything -ever-, I wasn’t sure I was doing it correctly (kept at it tho until I believed I wasn’t see air bubbles. To be certain tho, I bought a Motive Pressure Bleeder and pressure bled the system a bit more… for good measure. The “no clutch engagement” issue seemed resolved (shifting better than I’ve experienced since purchasing truck… DOT 3 was nearly black and leaks evident all about rusty M&S cylinders). FYI - my clutch master cylinder is angled -slightly- down toward engine.

Used truck yesterday (1st time since replacing clutch M & S cylinderls). Clutch did fine for nearly the entire time. At one point tho, I dropped the back end of truck off curb into the street (neighborhood park cleanup and we were moving limestone to flower beds). NOTE - Shocks r shot (new on the way) so such drops/bumps/etc. make u feel like your going to bounce right of truck.

With the drop, suddenly & temporarily, the clutch appeared to not engage (couldn’t find gear, grinding when I tried R… same issue that encouraged my replacing M & S cylinders, hoses, fluid). Finally found 2nd gear, after a short bit, and was able to move out of middle of the street. As I maneuvered truck to new location and killed the engine, the clutch issue kept occurring during this short trip across the park.

After I shut the truck down and let her sit for a bit tho (continued on with park volunteer work), I came back to use the truck and the clutch engagement issue was gone (not other issues since (this was yesterday).

Might I still have air in the system (having not bench bled the system first)?

Ps - all seals r leaking, but it’s not horrible and so I wouldn’t think low transmission fluid would be a factor?

Thanks you :)
 

fast 99

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Believe it or not bleed those backwards. Suck all the fluid out of the master, leave lid off. Then attach a rubber hose to the bleeder on the slave open the bleeder and pump fluid in from the bottom until master is full. Should work the first time but may take twice. I use a clean or new pump oil can but should be able to do it with a pressure bleeder.
 

SquareRoot

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Believe it or not bleed those backwards. Suck all the fluid out of the master, leave lid off. Then attach a rubber hose to the bleeder on the slave open the bleeder and pump fluid in from the bottom until master is full. Should work the first time but may take twice. I use a clean or new pump oil can but should be able to do it with a pressure bleeder.
Exactly. I keep telling people to reverse bleed the brakes and clutch and avoid the drama. One man job and 100% effective.
 

WFO

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I just pull the slave cylinder off and hold it hose end up, while pushing the piston in a few times until bubbles quit appearing in the master.

It does take another person to watch the bubbles though.
 

Ricko1966

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I stick a wrench and vacuum line on the bleeder,I connect the vacuum line to manifold vacuum,start the vehicle,crack the bleeder ,watch my level drop,tighten the bleeder,fill myvreservoir,put away my vacuum hose and wrench. Works for me.
 

viaminveniam1939

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Believe it or not bleed those backwards. Suck all the fluid out of the master, leave lid off. Then attach a rubber hose to the bleeder on the slave open the bleeder and pump fluid in from the bottom until master is full. Should work the first time but may take twice. I use a clean or new pump oil can but should be able to do it with a pressure bleeder.
What the best method for sucking fluid out of Master Cylinder? How will I know it’s all out?
 

Ricko1966

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What the best method for sucking fluid out of Master Cylinder? How will I know it’s all out?
Use a turkey baster,you aren't going to get it all out,just what you can readily see from the top and don't worry about getting all of it. You actually are just making room in the reservoir for the new fluid you are pumping in. You don't have to remove any,but it will make a big mess when the reservoir overfills and runs everywhere.
 

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