Clutch issue.

[UsernameRequired]

Brief history c1500 started life as 4.3 auto, now 5.7 manual. Now the trouble

driving the other day, and the clutch pedal became hard as a rock and would move maybe a half inch, then the push rod for the master cylinder broke. Master cylinder has been replaced but once hooked up to the hydraulic line to the slave cylinder it too would not move more than a half inch. Unhook the line from the master cylinder full travel in the master. Pull the line from the slave cylinder (this is an internal slave cylinder trans) and found the end of the line was frozen broke it loose it begins to move freely, place it on the truck start to bleed, right as it gets pressure there is a loud pop, pedal goes dead, valve in the line once again froze.

I cannot for the life of me find this line, advanced, orielly, napa, and autozone, all show the line as being 30in. This one is 37in

My question, has anyone had this issue with a Nv3500 swap? If so what hydraulic line did you use?

I did check with one custom hydraulic shop, and they said they couldnt duplicate it. currently, In the process of seeking out others.

attached pictures of the line.

 

[1998_K1500_Sub]

These guys near Indianapolis make custom stainless lines for brakes and clutches. You might try them (two URLs, below).

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[RichLo]

I've replaced many clutch and brake lines and have never seen a quick connect fitting like that and dont understand why you would need one?

How about go to a standard automotive hydraulic line?

 

[UsernameRequired]

The replacement gm parts have the same fittings just too short. At this point I almost want to switch transmission to one with an external slave. Haven't dealt with an internal slave until now...I have mixed feelings

 

[Schurkey]

Brief history c1500 started life as 4.3 auto, now 5.7 manual.

What was/were the donor vehicle(s)?

Maybe the extra-long hose is because that's what a Van, or Chassis-Cab needs, but your vehicle doesn't.

found the end of the line was frozen

Define "frozen".

Some folks use the word "frozen" when they mean "rusted" or "seized" or "corroded". Here in the Seasonally-Frozen Wastelands, brake-fluid based hydraulic systems freeze when the operator fails to flush the fluid. The fluid gets contaminated with water, which tends to sink to the lowest part of the system and then freeze as the temperature plummets.

 

[UsernameRequired]

The valve in the end of the hose becomes, stuck once the pedal starts to build pressure and will no longer flow fluid. Take the hose off press on the valve it pops, fluid starts to flow.

I bought a new slave cylinder today and different cable, once I pull the transmission and install everything. If it works I'll post part numbers, if it doesn't work...well it better work

 

[1998_K1500_Sub]

The valve in the end of the hose becomes, stuck once the pedal starts to build pressure and will no longer flow fluid. Take the hose off press on the valve it pops, fluid starts to flow.

There's a valve?

Someone please tell me its purpose.

 

[UsernameRequired]

I've been thinking the same thing, and it appears to be spring loaded... You can see it in one of the pictures

 

[Schurkey]

MAYBE a residual pressure valve. Don't know why one would be needed, but that's all I can think of.

IF (big IF) it's a residual pressure valve, it's defective--holding pressure in the wrong direction. Or holding pressure in both directions.

 

[Ryno3]

My guess would be that it’s a clutch delay valve, supposed to release fluid slowly in one direction to prevent shock load from dumping the clutch. Not 100% sure they used them in trucks. It would essentially be a open in one direction and an orifice in the other direction. I’m the past We had an S10 with manual transmission that we had to get the clutch master/slave and line from GM as we couldn’t find an after market one that was identical.