geoduke

I just overhauled my master and slave clutch cylinders. I put everything back together and bled the system without bench bleeding the MC. I did get to a point in the bleed process where there were no more air bubbles leaving the bleeder valve.

The problem is that the clutch is still very spongy at the top of the stroke.

Is it necessary to go back and bench bleed even though I'm not pushing any air through anymore? Is it possible for air to be trapped somewhere and not exit the system even though the fluid is coming out sans-bubbles?

I also had a question about the bench bleed. After the MC is bled how do you unattach the cable you used to bleed with and attach the cable that goes to the slave without having all the fluid run out of the hole?

Also, I realize clutch bleeding has been beat to death on these forums. I'm sorry. I searched. I promise.

***** I think I fixed the problem. I did the pump/bleed process as fast as my gf and I could go. After about a dozen in quick succesion another couple of large bubbles shot out and the clutch feels much better. *****

squishy321

i dunno if air might still be trapped in it, someone else might be able to help you, but if there is any air in it then chances are you will ruin your cylinders pretty quickly. Once i changed both my master and slave cylinders with used ones and didnt bench bleed, didnt know what it was, and in a week they were gone again. I chalked that up to crappy used parts and got another used master but a new slave, didnt bench bleed and soon enough the new slave was gone. got another new slave realized what benching bleed was, bench bled the master and its been good since. So in other words you may what to do it just to be safe. on the other hand that bit of sponge may just be the feeling of new rebuilt cylinders and some slack in the clutch bracket, but to be safe i would bench bleed it, what do you have to loose, maybe 5$ of brake fluid.

littlerunner

be careful having gf help bleed clutch or anything else,i used to ask wife to help with that stuff,she wont come near the garage now

YotaJunky

Yes, you can have air trapped in the MC even if you don't notice any bubbles coming out of the SC. Bench bleed the MC before reinstalling the MC in the truck, then give it a couple of light pumps with the hydraulic line fitting loose enough to allow a bit of fluid to escape, then tighten the fitting. The extra pumps will drive out any more air that may be trapped in the MC. Make sure you don't drain the MC too low, otherwise you'll have to start again.

After bench bleeding and tapping the pedal a few times with the fitting loose, I used a power bleeder to drive out all remaining air in the line and SC.

Troy

surf4runner

are you done yet my legs tired?
NOOooo dont let up the pedal

YotaJunky

You were pumping the what?! Brake pedal?! Out of no disrespect for my wife, because she was using a stick long before I started... but that's exactly what happened though - she was pumping the brake pedal while I was trying to bleed the clutch SC. That's one of the reasons why I got a one man pressure bleeding kit.

Troy