1990 GMC C3500 Repair Question
GMC C3500 Clutch Problem
You still might have air in the system.
Get some, about 6 feet, poly-ethlyene clear hose form home depot or lowe's that fits the bleed nipple on the slave cylinder bleed screw. Get and exact match 6 point or even better a flare wrench for the bleed sreww. Put some axle grease around the threads of the bleed screw so air cannot get back in. Get at least a quart size plastic bottle taht you can see through.
You will need an assistant to pump and hold the clutch pedal.
Put on the axle gease. Runt the hose from the nipple, through sixpoint wrench or flare if neccassaery, then run it to a point higher than bleed screw and into bottle. Clean off the master cylinder reserviour for the clutch and get some of the feccomend3ed fluid for it, see owners manual, keep it filled as letting it go emppty will suck air into the system.
Run hose over parts that will allow it to be higher that bleed screw and drop into bottle.
Top off fluid, then have assitant pump three times and hold pedal to floor. Release the bleed screw. If it take a lot of effort to move it , stop, you don't want to strip it. Get some BG Blaster or WD40 and soak it and wip it off and saok and let sit for a while. Try to do this as much as possible, overnight is best.
Re-attempt to lossen bleed screw. When it loosens tighten it right back up and when tight you can have assistant relaease the clutch pedal.
Repeat this process and nostice if there are large amounts of air in hose, there will be some from vacuum of hose sucking air in.
Repeat until fluid is clear and basically no air is in the hose.
Try this and see if it does not help. If it does not, There may be a problem with the pressure palte from the factory or an internal transmission problem.
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