Lizard928

Dan, I have run into this same issue on another car, though it isnt as consistant as yours and it comes back with more freeway driving. But when in the city it gets mushy, everything is new in the system too.

Dennis Wilson

Dan,

Same thing happened on my 78 after I rebuilt the MC. Took a complete flush of the clutch and brake system then two bleeding sessions to keep a decent peddle. Seems the new seals don't like air or old brake fluid while they are breaking in.

Dennis

Sailmed

+3
It doesn't make much sense not to do a complete change of brake fluid when ever we work on the brakes, or clutch.
This is an annual that starts causing problems when we become complacent about our fluid maintanance.

LT Texan

I'll flush the crap out of it, but I don't get why it worked so well for a couple months, then just went south.

Sailmed

When we install new hydraulic components in older cars, which have had numerous parts changes without fluid changes, we end up with "trailings", moisture, and other contaminents from old parts going bad - you possibly have a flake of rubber, rust, or even moisture from a old seal, cup, or fluid in the system - it can float around for months before getting caught in the system somewhere where it allows bypassing... As the cylinder experiences temperature differentials - the piece effects it different. Hydraulics are effected by contaminents, scratches in walls, tears in seals, air, and moisture - which when mixed with the fluid can allow for expansion and contraction at lower heat values. This absorbing of moisture is the main reason we replace brake fluid annually. Now - unfortunately the fluid should be drained and flushed after the old components are removed, and before the new components have been replaced. Your "flushing the crap out of it" may not remove the particle if it is stuck in the cup.... Cleaning and then bleeding the whole system may be required. Good luck!

LT Texan

The whole system was cleaned and rebuilt. I rebuilt the brake and clutch masters and the clutch slave. Replaced the blue hose and cleaned the system by flushing with brake fluid. I didn't replace the hard or flexible lines to the slave. Maybe some crap got into the slave.

What I can't wrap my head around is this, when I push down the clutch pedal, there is no resistance - when the master plunger goes down, where does the fluid go? If it leaks past the plunger, wouldn't I get leakage? I'm not losing brake fluid.

Someone help me with understanding this.

Well, I got this going for me, it's always easier the second time!

Dennis Wilson

Dan,

Did you adjust the pedal rod to keep a one revolution preload on the seals? I think this new spec was incorporated to keep pressure on the new seals until they have seated or hardened.

Dennis

LT Texan

Dennis, that one I didn't do. I had it where there was a little play. I take it the procedure it to adjust the rod where you first feel pressure, then one turn?

Like I said, I've got no leakage from the clutch master at the rod (nowhere else for that matter).

I wonder if it sucked air in thru the plunger instead of fluid thru the blue line?

Nevertheless, I'll start with the slave and work my way up.

Dennis Wilson

Dan,

Yep, adjust to no play then one 360 degree turn. Hopefully that will stop any leakage or bypass.

Dennis

LT Texan

flushed out the brakes with new fluid.

the clutch master was full of air, bled ala J Kempf method.

flushed the clutch system.

re-bled the clutch master.

Now I've got really good pedal. no play at all. (Dennis, I had only four turns left on the adjustment rod, I dared bring it down only to 3.)

Too it for a long drive around the neighborhood. Got it nice and hot.

no clutch problems at all.

Pedal still feels better than ever.

I'll see if air finds its way back in. If it does, I'm sure I botched the seals on the clutch master somehow.

thanks everyone

Dennis Wilson

Dan,

Good job!! BTW I rebuilt mine ala the Jay Kempf method.

Dennis

IrishLegend

I just noticed that the clutch boot was on the firewall is split and there is a little oil/fluid there. What does this mean?

Thanks.

Dennis Wilson

That means it's time for a replace or rebuild.

Dennis

IrishLegend

Thanks.
On that note:
Does anyone want to buy an '82 5-speed that needs a clutch, drivers side camshaft and the the TB/WP work?