Clutch Pedal Acting Up

total stab in the dark, but since you mentioned it happened going uphill, it could just be as simple as low fluid level?

Larry

Thanks Larry, I checked the fluid level, and it looks fine.  Maybe I will go park on the incline and see if anything changes.

When it acts up it feels like there is no clutch tension for the first 1/4" before there is any pedal resistance.   Feels very similar to a brakes when they have air in the line.

I will bleed the system today and see if that helps.

It's an early model pre-L without the effort reduction kit.

Thanks again.

John

Rob on this site was having the same problem.  New slave cylinder and pedal would not pump up and get pressure.  He was bleeding it many ways with no success.  Not sure how it turned out.  He had also replaced the clutch master.   I am beginning to wonder if these replacement cylinders are flawed in some way that they let the fluid pass.

So...  I went out and opened the cap and noticed two things.

1. The brake fluid is the color of oil after 5K miles.  Very dark.

2. The screen to keep debris out was floating inside the reservoir and the rubber gasket that holds it up was broken.  I did find a few small specs of the gasket inside the reservoir after I vacuumed it out.

Weird thing is I have about 500 miles on brand new MC, Slave and Fluid.  I know that I bled the system the first time until new fluid was coming thru the master.

Anway, I refilled the system with completely new fluid and bled it again.  Took if for a drive and it does seem better but still have some slight sag on the initial push of the pedal.

I will keep an eye on it for now and see how the DOT 4 fluid holds up.

Thanks,
John

On my car the pedal had a… well,  not really a hard spot… felt like you “pull a magnet off” resistance…  So my guess is that the clutch wasn’t adjusted correctly from the get go! I’m thinking the 2 flat arms connecting to the pedal arm just were not is the correct angle in relation to the leverage of the pedal arm! (Not enough angle)

It is a known problem that those arms wear in and having oblong holes, which may  create that problem… You might want to check that as well..

i turned the rod 2 turns in and now it feels even… No “hard” spot in the beginning!

The black brake fluid is the seals in the master cylinder deteriorating during use.  

Thats concerning considering I've had it on the car a couple of months and around 500 miles of usage. 

The black color is probably carbon black leached out of any rubber touching the fluid, and as was said, it can come from the seals in the master OR slave, from rubber hoses anywhere in the system or from that reservoir gasket that took a bath. The color is not necessarily harmful unless its also gritty between your fingers. Most cars of any brand have black hydraulic brake/clutch fluid after awhile. Just keep an eye on it.

I think a very slight hard spot at the beginning is a good thing given that there is no space to place the left foot next to the pedal, this allows you to leave your foot very lightly on the pedal while being sure that the thrust bearing is not in contact with the clutch.

Do you have a plastic pressure hose in line anywhere on the clutch circuit ? This could be causing the discolouration.

A 'slight' hard steering spot may be due to a chipped or worn tooth on the mild steel rack gear. The pinion gear is hardened so it doesn't wear much. Using the lazy mechanic's method of adding grease instead of gear oil for lube inside doesn't help the wear problem.

BTW, most people that change the stock steel/rubber/plastic bushing for a bronze one don't take the time to deburr worn teeth on the rack gear. Then while reassembling the steering rack, the burrs ream out the new bushing so instantly, your new bushing become a  worn bushing.

I replaced the plastic hose with a metal braded line when I replaced the clutch M/C and Slave. 

Thanks,

John

My favorite subject!!

Dark fluid is a sign of the seals breaking down. It has nothing to do with any hoses downstream as the fluid acts a solid column and only moves back and forth a bit. My OE style masters (all 3 of them) would start getting dark within 100 miles. There were also solids in the fluid, not a good sign. A Wilwood clutch master has resolved that problem and the lovely leaking bottle problem.

My recent bleeding problem was solved by realizing that I did not get the arm/spline orientation correct when putting things back together. What I thought was air/no pedal, was really just the system using up a bunch of free play. Fixed that, no problem now. I did waste a bunch of brake fluid and brain cells sorting that one out!!!  (It did force my wife to get into the Pantera to help with bleeding!)

My recommendation - stay away from any Pantera vendor parts that hold/use fluids!!

Thanks for the advice.  Any chance you have the Wilwood part # on hand?

I have the Wilwood brake M/C and proportioning valve so might be nice to have everything match in the frunk.

Thanks,

John

Rob - that is great news.  What slave cylinder did you end up using that worked?  The Alfa part I suggested to you?  

Lee

John - the Wilwood part # is 260-15098 ($77.36 at Summit - my favorite vendor!!). It does require a braided hose and various adapter fittings to hook it up.

Lee - I ended up returning the short bodied Alfa cylinder to Centerline. In my throes of problem solving, I didn't want to introduce another variable. I ended up with an OE type slave from Wilkinson (I think this one is showing signs of dampness now??). The Alfa part from the Montreal(?) with the same body length may be in my future.

For now - it is time to replace the radiator/fans and add a Parker Funnelweb intake manifold!!

Thanks Rob, I will give it a shot.

John

John - I forgot to mention that with the Wilwood, the hole spacing does not match OE (maybe 1/4" off - not huge). There are posts on here showing modification to the holes on the Wilwood to accommodate the spacing. I opted to modify the holes in the AL bulkhead. The hole enlargements are covered up by the Wilwood or the OE style masters. Some folks seemed troubled by that, but these cars are not 7 figure collectables!!

Thanks Rob.  Keep us posted on the Slave.

The Montreal slave which I now believe is the correct replacement:

https://classicalfa.com/mn014-...utch-slave-cylinder/

Thanks Lee! I sure wish I could get a drawing for this!?!

You should call Classic Alfa as I see they are Out of Stock.   SIGH.....

One more option I had found - https://mrfiat.com/italian/alf...-slave-cylinder.html

Mr fiat may be a better option. I’ll give them a call to see if they can provide dimensions. Thanks again!