Clutch MS Problem

Dave · Post by **Dave** » Tue Feb 15, 2005 10:57 am

Hi guys,

I've got a problem in my clutch hydraulic system and a theory about it to run past you. Last summer, I installed a re-man clutch master cylinder, slave cylinder, and all new lines. So, the entire system is "new". Within about 3 days I noticed the fluid in the clutch master cylinder cup turning black. I did a similar refurbishing to the brake system but used Nissan calipers, master cylinder and all new lines. The fluid next door in the brake system is nice and clear, nearly a year later. So, I know it's not a heat issue. I also noticed that if I pop the hood after just a few minutes of driving, the lid on the clutch master cylinder cup has popped loose and will be sitting ajar.

My theory is that the seal in the master cylinder is garbage, hence the black fluid. I also suspect that some of the pressure generated by pressing the clutch pedal in is escaping past the seal and instead of going into the clutch line, is pressurizing the reservoir and popping the lid off. Does this sound like what might be happening?

Thanks!

SER240Z · Post by **SER240Z** » Tue Feb 15, 2005 7:22 pm

You know I think I have the same problem with my '69. I think the lid pops off due to the hood though. I've noticed that on the passenger side of the hood there is a little indentation where the clutch master reservoir would be if it were a right hand drive. I also have a little rubbing spot on the hood where the master hits. As for the black fluid, I had no idea why, since my system was also farely new.

Scott

spriso · Post by **spriso** » Tue Feb 15, 2005 8:04 pm

This is a common problem with the high-windshield cars. What we do to fix it is get an offset clutch reservior from a mid-90s Mitsubishi Eclipse.

The Mitsubishi uses a master cylinder made by Nabco, a Nissan supplier. It is too long in its original configuration, but we cut them down and they slip right on.

Here is a picture of the modified part on Jason Brainard's SR20DE powered 68 roadster that we built a few years ago:

Just some of the details that we do to make our conversions more unique...

Michael
spriso.motorsports

Dave · Post by **Dave** » Wed Feb 16, 2005 4:20 pm

Thanks guys! I'll pay a visit to my local mitsubishi dealer.

spriso · Post by **spriso** » Wed Feb 16, 2005 5:44 pm

Skip the dealer-- just hit your local Pick-a-part! They are always littered with tons of broken Mitsubishi's!

Spriso

Dave · Post by **Dave** » Thu Feb 17, 2005 1:20 pm

I would but I don't was some scabby old MS cup sitting next to my nice, clean, new brake MS cups. Man, I never used to worry about cosmetic stuff like that until I met you! Thanks a lot Michael!

spriso · Post by **spriso** » Thu Feb 17, 2005 1:51 pm

I always find that the Mitsubishi's are rotting in the wrecking yard before they get too grungy...

If you find the part number for the new part, pass it along, it will be great to have in the archives!

Michael

SER240Z · Post by **SER240Z** » Thu Feb 17, 2005 4:48 pm

Could you just cut down a reservoir for the roadster instead? Or would there not be enough volume after?

Scott

Dave · Post by **Dave** » Thu Feb 17, 2005 6:04 pm

Wouldn't Jason have the part number? You can't tell me he found that MS cup in the bone yard. It's too clean!

I was thinking the same thing about cutting the cup down. It's can't be more than 1/16 of an inch or so than needs to come off, otherwise the hood wouldn't shut right.

spriso · Post by **spriso** » Thu Feb 17, 2005 6:16 pm

No, I don't think Jason will have a part number for it, since I pulled it off of a Mitsubishi Eclipse at our local yard. I have installed these on three or four cars, and they have all come of of crashed Mitsubishi's.

The best part is when a fellow roadster owner looks down at it and wonders where on earth you found it!

M

Dave · Post by **Dave** » Fri Feb 18, 2005 9:29 am

I'm shocked you found one that nice at the wrecking yard. I figured they would all be spray painted, covered in racing stickers, or wrapped in neon....

I'll check this weekend and see what I can find.

scotty · Post by **scotty** » Mon Feb 28, 2005 1:22 am

will this work on a low windshild car?

spriso · Post by **spriso** » Mon Feb 28, 2005 10:31 am

Yes, it will work no problem at all.

Michael

Dave · Post by **Dave** » Mon Feb 28, 2005 11:19 am

OK, here's what I found. The clutch master cylinder cup you are looking for is from a 1990 or 1991 Plymouth Laser or Mitsubishi Eclipse. The Eagle Talon from those 2 years might work as well but I'm not sure. From 1992 on, the cup is still offset but got a lot taller and will not work. Another option would be the clutch master cylinder cup from a first generation Altima. It too has the offset design, though the top 1/2 of the cup tilts to the side. It will work, but cosmetically it will look a tad goofy.