Pitting INSIDE my Clutch Slave Cylinder (88 Formula) (Page 1/1)
robmox JUN 21, 10:55 AM
So, I've been having a small clutch system leak, so I ordered a slave cylinder rebuild kit from Rodney Dickman (he was out of new slave cylinders). The transmission in question is "MG2 Transmission, manual, 5-speed (Muncie) 3.61 ratio" (RPO Code MG2). So, when I took that unit out, I pulled it apart and removed the plunger to notice that there was rust inside. So, I cleaned it out with parts cleaner, and gently brushed away the rust with a brass brush to find that the area where the rust was had pitted pretty significantly. My first questions is "Why the hell is there rust inside my slave cylinder?" But, it appears to be still leaking, just at a much slower rate. Should I just replace the whole unit? And if so, would you recommend getting a second rebuild kit so I can put in those upgraded components?
Raydar JUN 21, 11:54 AM
Clutch (brake) fluid will tend to absorb any water that it comes in contact with. Hence, the rust.
I've wondered if you could take a small hone, like a brake cylinder hone, and "dress" the slave cylinder bore. But I've never tried it.

Is Rodney going to restock his slave cylinders? Did he offer a time line? I know he's trying to sell his business. I hope he's not going to let his stock run low, in anticipation of that.

Rodney's rebuild kit (I believe) is designed for his own - as well as other - slave cylinders. I would be inclined to hold out for his, because it's a superior piece, but you know how much leakage you can put up with.

[This message has been edited by Raydar (edited 06-21-2022).]

robmox JUN 21, 12:11 PM

quote
Originally posted by Raydar:

Is Rodney going to restock his slave cylinders? Did he offer a time line? I know he's trying to sell his business. I hope he's not going to let his stock run low, in anticipation of that.

Rodney's rebuild kit (I believe) is designed for his own - as well as other - slave cylinders. I would be inclined to hold out for his, because it's a superior piece, but you know how much leakage you can put up with.




I believe on his site, it said he lost the manufacturer. I don't remember it offering a timeline on a restock.

I'll see if I can hold out that long. At this point it's just a slow trickle, so I can put up with it for a bit. I've actually gotten used to checking my clutch reservoir every time I take out my car.
Raydar JUN 21, 02:28 PM

quote
Originally posted by robmox:

I believe on his site, it said he lost the manufacturer. I don't remember it offering a timeline on a restock.
...



I looked. You're exactly right. His manufacturer went out of business. His site said that he doesn't anticipate there being any more stock before his business sells.

Wish I was a bunch younger (I'm about the same age as Rodney), and had a bunch of money to throw at this. Oh yeah... and some fabrication skills. *sigh*
Patrick JUN 21, 04:00 PM

quote
Originally posted by Raydar:

I looked. You're exactly right. His manufacturer went out of business. His site said that he doesn't anticipate there being any more stock before his business sells.



I don't currently need a replacement clutch slave, but that's not good news.

Larryinkc JUN 22, 10:02 AM

quote
Originally posted by robmox:


I believe on his site, it said he lost the manufacturer. I don't remember it offering a timeline on a restock.

I'll see if I can hold out that long. At this point it's just a slow trickle, so I can put up with it for a bit. I've actually gotten used to checking my clutch reservoir every time I take out my car.



I have a Rodney Getrag slave if you are interested. I have a 3800 swap with a Spec Stage III+ clutch and aluminum flywheel and ended up going to an Isuzu slave cylinder. The Getrag slave was on the car for less than 200 miles. When I pulled it I flushed it out with brake assembly lube before storing it. It moves freely, I removed the boot and the bore is clean and smooth. I'll take $60 shipped for it.
theogre JUN 22, 11:54 AM

quote
Originally posted by Raydar:
Clutch (brake) fluid will tend to absorb any water that it comes in contact with. Hence, the rust.

Brake fluid pull water from the air.
See my Cave, Brake Fluid

Piston Seals doesn't seal completely and pistons need that thin film to lube them etc.

Pitting outside, between piston seal working area and dust boot, is often rust just for that.
Pitting inside, between working seal area and end of bore, is often crap sitting at bottom for years or decades. Same issue cause MC failure after "Pedal Bleeding" for brakes. See brakes in cave.

You can't "hone the bore" in aluminum cylinder when this happens. You have to replace then.

------------------
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