#$%@ clutch bleeding

[nola mike]

so just bought a '97 4.0L. when i bought it, there was an issue with hard shifting--guy thought it was the slave, which he replaced without improvement. so then maybe it was the MC. he was going to replace it, but i drove it around for a few days, which seemed to help the shifting quite a bit. still not perfect though, and since he was going to replace the MC, i let him. now we're back to square 1 (or worse). i helped him bleed the damn thing for 1-2 hours today to no avail.

symptoms:
1. shifts fine with the truck off.
2. shifts fine with the truck moving.
3. shifts grudgingly into 4th, sometimes 3rd, with the truck running.

we bled it with the MC inverted and removed from the firewall. there doesn't seem to be much play in the pedal, but i don't have much to compare it to. any other suggestions? any chance this is something worse than hydraulics? i had read that the earlier trucks self bled with driving, but not the later ones--but this truck seemed to improve after driving it before...

 

[177CIOfPureLove]

Oh jeeze man. I dont want to tell you how many hours and ounces of brake fluid I had to run through my set up after the hose blew out of the new slave when I put my motor in (I, like a fool, tried to keep my old quick connect hose to save money, the aluminium rotted and couldnt hold its self clipped in after driving it for a few miles) so needless to say, I had to start from the beginning. I did not invert my MC, which cost me hours of bleeding under the car. I would bleed it conventionally, and let it sit for a while with the cap off of the reservoir, let gravity take over. If need be bleed it again. I dont think there is a way around bleeding it some more. The gravity approach was told to me by an old man, and after I did that it performed perfectly. Good luck and happy bleeding!

 

[lepp1892]

Man... i have bleed my clutch system like 4 times for various reasons and i have never had as much of an issue doing it as some of the people on here... maybe i just get lucky...

 

[Will]

I bench-bled the master and gravity bled the slave. The second time was so easy I don't even remember it. Ther first time was a bastard. The key is bench bleeding the master. The rest of the system is well below and as long as you keep the resevoir filled, it will bleed.

But there can be other causes of hard shifting. I don't know what they are but if you have pressure high up in the pedal then you may have it bled well enough. It doesn't take that much movement of the slave to release it enough to shift. If you are racing you don't push the clutch all the way in.

 

[Shran]

Gravity bleeding didn't work at all for mine. I tried pulling fluid through the slave with a vacuum pump but that did not work at all either. We finally just used a plastic hose from the slave to a jar of brake fluid and pumped the crap out of the pedal. Seemed to work ok.

 

[nola mike]

But there can be other causes of hard shifting. I don't know what they are but if you have pressure high up in the pedal then you may have it bled well enough. It doesn't take that much movement of the slave to release it enough to shift. If you are racing you don't push the clutch all the way in.

yeah, i may try to bench bleed the MC--i had tried it with the quick disconnect disconnected at the MC, which didn't work at all. the shifting is only difficult with the truck stopped, so the flywheel is spinning but the pressure plate isn't. that should be the time when clutch disengagement is most important. what else could it be, assuming the only shifting difficulty i have is at a dead stop?