Steely

As it gets closer to winter, I was thinking that among the other things I want to do, I would definitely like to improve the action on my clutch pedal. It is smooth, but quite stiff to depress. I saw in bentleys that I could make an adjustment on the pedal cluster (eccentric allen bolt), but this gave me limited to no improvement, leading me to suspect my clutch master cylinder as a potential source of extra resistance - would anyone know? It's tough to the point of me not getting used to it, nor being able to learn from touch or feel when the clutch is actually engaging / dis-engaging.

It's an 87 with 95K, maybe 10K on the clutch and slave cylinder replaced by the PO. The hydro fluid was bled a year ago before my time, and the clutch has always been stiff to me, but I still think it could be easier - it's quite a ways off from buttery. The CMC boot is dry and has a tear, but there is no evidence of any leaks. I do not know if the clutch circuit was ever bled. In another thread, I read where Steve Wiener has replaced these as a matter of course in certain instances.

Could the CMC be the source of my tough pedal? Should I consider replacing it, or should I discount this (don't fix if it ain't broke), and work on my leg strength instead? It's just not as easy to drive as I expected or want. I may try to figure out if I can isolate the issue by disconnecting the CMC from the clutch pedal crank in order to see what force just the spring provides. That should tell me once and for all if it is the CMC, but would a new one necessarily be easier? Any thoughts would be appreciated.
Thanks!

WPOZZZ

Check this out. http://tech.rennlist.com/911/pdf/915_vs_G50.PDF

gbailey911

Dan, if the car still has the original clutch in it, the clutch fork is probably the reason your clutch is so stiff. The original fork had small needle bearings where the fork pivoted in the bell housing. Over time the bearings get dirty from clutch disk dust and dry and eventually will sieze to the shaft. The fix is a new improved fork and larger bushing (vs bearings) but requires removing the transmission from the engine (engine-transmission drop). I did the job on my 87 about a year ago. Once done, the clutch action is smooth as butter.

Steely

hmmmmm, verrry interesting.
The clutch was replaced earlier, I'll contact the PO and see if I get an answer.
I guess you can't tell if the mod was done by looking from the outside?

Thanks guys.

Steely

Thanks again for the tip guys.
What's the best way to diagnose this? Not that I'd be able to do something right -away unfortunately.
Would checking the pedal operation with the slave cylinder removed from the transmission be a logical step? I am trying to find out if the fork and bearing were upgraded too.

KC911

That would suck if the clutch fork upgrade wasn't done at the time. I'd bleed (flush) the brakes/clutch too, just because . Do you have a point of reference as to how this G50 "feels" compared to other cars, or have others driven yours?

Keith
'88 CE coupe

Peter Zimmermann

Good news, yes you can. You need to raise the back of the car high enough to get under it (OF COURSE, USE ANY/ALL PRECAUTIONS SO THE CAR CAN'T FALL ON YOU). Grab a flashlight, slide under the driver's side until your head is below and slightly to the rear of the left axle. Look up toward the clutch slave, just below it, on the side of the diff housing, you will see a metal tab that's roughly 1.25" x 3/8". The tab is held by a small bolt (10mm wrench size head) at one end. The other end will either be welded, or it will apply pressure against a plastic dust cap. If it's welded it's the original setup, and would explain your heavy clutch.

imcarthur

Here is what Pete is referring to. This is the tab on an unmodified 87. Very visible center upper right.



Ian

DRACO A5OG

After what Pete Z recommends try this:

According to Bentley GUide, G50's clutch pedal assembly can be adjusted for firmness.

Just did it for Rnln.

Need a 17MM Allen and 13 or 14 MM Wrench.

Remove wooden panel to gain access, you will see where the pedal is attached and notice a hole where a factory long allen would fit through. A standard allen works too, slightly loosen the lock nut and then use allen wrench, move towards the rear for firmness and towards the front for a softer feel. 1MM at a time.

Note the adjustment bolt is oval in shape so if you over do it it will automaticaly soften too much by design then you will need to start again.

Peter Zimmermann

Great picture - thank you!

imcarthur

You're being kind by not mentioning all of the crud. When I do the upgrade . . .

Ian

old man neri

It's a protective undercoating.

Steely

Was out of the loop today - celebrating mom's 80th b-day! Was happy to see all of the responses.

My PO wrote me back to essentially say he didn't know. He had the clutch replaced due to excessive pedal force, but no where in the documents does it specifically mentioned the fork or fork bearing. He did the p-plate, clutch, TOB, TOB bearings, trans clutch shaft(?), and the slave cyl. I wrote the mech, but no response (yet).

I have nothing definite that says he did it.

KC911 - a point of reference? Too few p-cars, although I did drive stick for years, mustang, toyota, mistsubishi, jeep wrangler. The feel in this car is harsher/tougher than most, but I cannot compare it to other p-cars since this is my first. As I read and drove this more, I really began to wonder.

Peter - I'm a little embarrassed to admit I do not have a hydraulic jack or stands, but I will check under her as soon as I can. Thanks very much for the detailed method - I will definitely be checking, probably with a neighbors help. I will be looking thru the PET to see how this pic jibes with the exploded assy views so I can get a pic in my head.

Ian - A picture is worth....a thousand thanks!

DRACO - Actually this was first thing I did - I hijacked a thread over at pelican after reading over there what rnln did on the subject - the adjustment provided limited help. At no time did I ever have insufficient force to return the pedal back (the pedal always returned forcefully) - as if the adjustment of the eccentric was too small to be of any significance. Incidentally in mine it was an 8mm Allen. Rnln never knew if you loosened the 13mm nut (Bentley doesn't say oddly), and so I did not. I rotated the bolt away from the driver (coincidentally CCW wrt to nut so it wouldn't get tighter). Bentley recommnds scribing a ref line across the bolt/nut, but this is ridiculous since you can't see it. I did the adjstmn't with the goal of relieving the torsional load on the spring as much as possible (see first post). it was at this point I began to wonder if the Master clutch cylinder could be fighting me, or if it was something else.

Guys, you're the coolest. Thanks for the help. I will be getting under there asap, will find out, and will update here. honest.

Steely

KC911: BTW, I'm not a PCA member (yet), and don't know any p-car drivers (seasoned or otherwise). You're right - I really should get someone else to drive her and give me some feedback.

DRACO A5OG

Hey Dan,

You do need to loosen the nut in order to make proper adjustment then re-tighten the lock nut. Yeah, 8MM sounds correct, sorry lost my mind 17MM would have been huge, LOL.

Jim