NanaimoRx-7

Well, it's been 4 years and finally something major just broke of it's own accord. I can't be mad at that kind of service record. Anyways the other day I was leaving the driveway and noticed the dis-engaging point was really low, nearly to the floor. No biggie, just a quick bleed and I'll be set.

I bled the lines and the pressure got better, but in the span of sitting in the car for 30 seconds it went totally limp on me. I can pretty much throw the pedal to the floor with 2 fingers. I went to bleed it again and noticed that it was developing ZERO pressure (no fluid out of the nipple). So I drove it down the the mechanics to have a look-see, what an adventure. I can't select 1st gear while the car is running, so at stops I had to shut the car off, select 1st gear and roll start it. Good thing I've been rev-matching (fairly accurately) for the last 3 years, so it wasn't too much of a struggle. They couldn't bleed it, or find the problem either. Suggestion: Might be the pressure plate, and I should replace everything PP, clutch and all the hydraulics.

I took it home to think about it and play a little more. Lying in the footwell operating the clutch I could hear fluid bubbling, and noticed the backside of the seal was wet. So I went ahead and ordered a clutch master cylinder. The parts place had no listing for '80, just 79 and 81-up. I went with the '79 for the 5/8's bore. The only difference I see is that the hard line angles slightly away from the engine, opposed to the perpendicular fitting on the old one.

Installed, bled, no difference. I think I bled it pretty well, I'll be giving it another shot today. What do you think I'm looking at here? I'm thinking about dropping the tranny to look at the PP, but I'm looking for ideas.

Thanks in advance guys. -George

Wankelguy

Have someone pump the clutch pedal while you observe the slave cylinder's operation. If it's pushing on the fork okay, it's the clutch itself. If not, it's probably the slave cylinder. Doesn't anyone rebuild their own hydraulic cylinders anymore? A rebuild kit is cheap and if the bore isn't too severely pitted, it can be honed and rebuilt to work fine. Here's another tip: instead of buying rear wheel cylinder rebuild kits, just ask the auto parts guy if they have a blue Wagner brake parts box. Then just match up your rubber cups with the ones they sell bulk out of that box. Just a little cheapskate wisdom.

syklone

Did you replace your clutch recently? When I did mine, I tweaked something in the release cylinder and it doesn't hold fluid for more than a couple of weeks. Not exactly your problem, but similar. I'd check someware around the release cylinder for leakage, and just replace it if its bad. I just bought a new one on mazdatrix for $45. Not bad for a new part.

NanaimoRx-7

I always had a small amount of fluid disappear from extended 'spirited' driving, but I never found the source of the leak until I yanked the master cylinder. I'm going out to pull the release off and inspect it. This is really starting to get to me.

Wankelguy

$45 for a slave cylinder=highway robbery.

NanaimoRx-7

I GOT IT !!!!!!!!! Ahhahaha, finally. Fixed (for now). I think it was a combination of the hardline fitting and bleeding. When I re-bent the line I guess I wasn't accurate enough the first time and the line wasn't seating properly against the master cylinder although the fitting did screw in. Did a better job bleeding this time too, picked up a 6 dollar self bleeder that works great. The pedal is stiffer than I can ever remember it being.

I was down at the parts place trying to get a new section of hardline (I'm going to redo the bends properly and get the bracket back to the stock location) and a new bleeder screw for the slave cylinder. I need to know the thread pitch and size of that screw if anyone's got it. Oh yeah, brand new slave 20$CAN, more often than not Mazdatrix is robbery on stock parts.

Thanks for the help Wankleguy....that's a good timing on that brake tip too as I'll be tackling that job soon. Much appreciated. -George

NanaimoRx-7

Well, that lasted all of a 10 minute drive. Went to leave from a light and the clutch pedal felt a little low again. Few minutes later and she's totally gone again, I pick up bcty and book it back to his place to inspect it. Rebleeding by hand, and it's worse than before. Grrreat. So I drive home, here's the thing. I'm actually starting to like this no clutch thing, it's not that bad. The only funny part is starting the car in gear when I hit lights, other than that I can shift normally, even downshifting isn't a problem.

At home I break out the good tools and take another look. I get out the sweet bleeder helper and go to town. Hmmm no pressure, again. So I'm under the hood operating the fork by hand, and I hear this noise. The same squishy noise the old master master cylinder was making, but this time it's coming from the slave. I pull back the dust boot, and brake fluid a plenty. Always replace in pairs people !!! Looks like the slave wasn't up to taking more pressure than it's had in years and let go. Ha ha, can't blame it. Yesss, more time to play with the car.

Coal

w00t! Progress

Good to hear that you've had better luck with that man. The other night over at your place was fun, but a dissappointment when it didn't work as intended

Hopefully replacing the slave finishes that problem

bliffle

I had that problem last summer and solved it by replacing the flexi-hose going to the Slave. It was clearly broken when I removed it, but it was not evident where the fluid was going. $13 from Mazdatrix. This summer I have to replace the hose, slave and master on the 85. Always replace them all together.

B

Pele

iTrader: (28)

I thought I had a how-to about clutch hydraulics replacements around here... Damn. It has been a while. Oh well, yeah.. replace in pairs as they get used in pairs and wear out as a pair...

In comparison to the cheapest local parts supplier for the Hydraulics, Mazdatrix wasn't too far off, except for shipping... Unless they've changed thier prices...

NanaimoRx-7

Thanks. Yeah I replaced that hose last year when it developed a bulge the size of a small egg...wrapped it with duct tape and prayed for a week while the new hose got here.

MIKE-P-28

iTrader: (1)

Sounds like a clutch slave and/or master cylinder problem, I havent had a 7 yet this hasnt happened too. Theres a bright side tho, I got the one off my 85 here, it was recently replaced before I did the motor swap, and wouldnt work with the t2 trans, so make an offer and it may be yours

Rotary Revolution

****, this just happened to me this morning. Ill be bringing my 80 7 so RX7 Heaven in Roseville this week, so have the slave and master cyl replaced!

Suparslinc

My clutch has been two inches of the floor for as long as I can remember; all the bleeding doesn't help at all.

Rotary Revolution

Well, now the pedal doesnt work at all!

NanaimoRx-7

Mine's been great since I replaced the slave, better than when I got it 4 years ago. The master was empty when I got, so I think it was a long term leak.

It also bled much faster with the new slave, 5-6 pumps to get all the air our and start pushing solid fluid. The slave was a piece of cake to install, 5-10 minutes tops, the master is pretty easy once you figure a way to get at the two nuts in the footwell. What a PITA !!!

Wankelguy

Here's another slave cylinder tip: The older ('74-76) Couriers had an adjustable length pushrod. Makes it nice to be able to adjust the freeplay at the slave end, when needed. I got a couple of 'em for about a buck apiece last time I went to the junkyard. -WG

JALVORD_2003_68

here's some automotive wisdom: replace the line slave cyclinder and the master cyclinder and bam! problem solved!