88 MR2 Clutch no good after sitting for some time..

[Red October]

Well here goes. My girlfriend's MR2 is finally all ready to go back on the road after sitting without moving for about 8 months or so. The motor runs strong, comes up to temp, develops oil pressure, etc, all that good stuff, but there is a strange issue with the clutch. The pedal is very, very soft, like you're just pushing against the return spring, and nothing happens when you put the clutch in -you can't put into a forward gear at all and reverse just grinds as if you didn't have the clutch in. I checked the reservoir under the hood and found that it seemed dry of clutch fluid... I also found a weird rubber gasket sort of thing in it that looked like it was supposed to seal with the cap; it's possible to force the cap on with this thing in it and it seals, but for some reason that doesn't seem right. I'll go out to the driveway and check my own car (which has a perfect clutch but is off the road for other reasons... damn paperwork) to see what this is supposed to look like, but can anyone clue me in to what is going on here? Filling the reservoir up with DOT3 brake fluid as it requests did nothing, and pumping the clutch perhaps 200 times did nothing as well.

[toyotaspeed90]

try bleeding the system first....

just adding fluid will NOT make the fluid run through the system.... if there's nothing past the master cylinder in the lines, then it may not start...

you can first try by loosening the bleeder valve on the slave cylinder then pumping the clutch to see if the fluid goes through... but on most mr2's it won't.... if it doesn't, go get a brake bleeder vacuum pump.... at most they're $40 at a local auto parts store

[The Money Pit]

When operating the clutch, have someone watch for the appropriate movement at the slave ... if not, bleed ... the rubber in the cap may need to be replaced ... it does happen, but should have no effect on the clutch operation ... you could always swap caps for piece of mind ... with finding it empty, there is a leak ... fill, bleed, locate leak and correct ...

Another possibility is the metallic in the clutch disc has rusted to the flywheel ... it can give a soft felling to the pedal and as it isn't disconnecting, give you those symptoms with shifting ... it was something I experienced with race cars ... sit all winter, then .....

The cure for this issue ... start and warm the car up ... then start it in gear (second) ... then keep your feet busy ... hold the clutch down, increase the rpm and apply the brakes ... usually before the car comes to a stop the clutch will snap loose ... with the clutch pedal depressed, the only thing keeping you moving is the rust ...

do NOT use any lubricants ... and only consider the clutch is rusted after verifying proper slave cylinder action ...

regards ... Ken

[feral4.mr2]

this is a master cylinder problem for sure.

when you fill up the reservior with new fluid you will need to undo the brake lines out of the master cylinder to alow the fluid to fill the cylinder area. once fluid comes out the lines you have undone do them back up and top up the reservior.
then you can progress to bleed the system from the slave cylinder as normal.

problem with leaveing the car sitting so long is that brake fluid absorbs moisture, this moisture resides under the brake fluid and in the case of master cylinders pits the lower wall of the cylinder. at that stage pumping the pedal will get it to work, you'll notice when stopped at traffic lights for instance that the pedal will slowly seep to the floor while your foot is on the pedal and in most cases you'll find brake fluid seeping down the carpet inside the cabin from where the brake pedal rod enters the fire wall.

other than buying another brake master cylinder, best thing i've found is to get it re-sleaved with a stainless steel insert that will not pit in the future.