No return spring boss on clutch slave -- OK?

[BoldUlysses]

Hi guys. I'm reassembling my clutch system, and my new clutch slave cylinder lacks the old unit's boss to hold one end of the spring that goes from the release fork end.

The upshot is that I won't be able to use the OEM release fork return spring with the new clutch slave. Will I be okay?

[olzed]

I replaced my slave 3 or 4 months back, with no spring, and no problems.

[BoldUlysses]

Awesome; thanks.

[Carl Beck]

The clutch slaves for the 70/71 Z's had adjustible clutch push rods - they need the return springs. For 72 Nissan went to a self adjusting slave - and they do not need a return spring. I've never used the newer slaves on the older cars - so I don't know if it would be a future problem or not. Can't think of any reason it would be...

FWIW,

Carl B.

[BoldUlysses]

Hmm. My old slave had an adjustable push rod and the return spring, and my new slave had a shorter, non-adjustable rod with no spring. I had to use the old, adjustable rod since the hole in the release fork was too big for just the rod by itself (it's sized to contact the spherical nut on the adjustable rod).

So I have: New slave, old rod, no return spring. Think I'll be okay?

[olzed]

Should have said -- my 240 is a 72.

[240260280z]

I have read where some drill a hole in the newer slave cylinder where they can hook the spring thus maintaining the function.

Read post #7 here: Early Clutch Slave Drilling Spring Hole

Edited May 22, 2012 by Blue

[Carl Beck]

So I have: New slave, old rod, no return spring. Think I'll be okay?

The spring was there - to hold the Clutch Fork firmly against the adjustment nut on that rod, when the clutch pedal was let out. So that there was no residual pressure holding the throw-out bearing against the Clutch Pressure Plate fingers. {kind of like "riding the clutch"}

Without the return spring - the rod sticking though the hole in the sheetmetal Clutch Fork - "can" get in a slight bind...and thus be prevented from releasing all the way. Most likely not a problem for a car driven infrequently or less than a few thousand miles per year.. So I doubt it would be a problem with the self adjusting slave.

You will however have to manually check the clutch adjustment every few thousand miles to assure that there is no pressure on the Clutch Fork when there isn't supposed to be. Because the adjustable rod will prevent the new slave from actually being "self adjusting".

You could make a little bracket out of 18 gauge sheetmetal. Drill a hole big enough to slip one of the bolts that holds the salve on - though one end. Then drill a small hole for the spring in the other end. You could almost use a Pop-Top Tab from a beer can - but you get the picture...

FWIW,

Carl B.

[BoldUlysses]

Thanks Carl. FWIW, there wasn't any pressure on the release fork when I installed the new slave.

Debating about whether to:

1. Grease up the rod nut and call it a day. Car certain isn't, and will never be, a daily driver. Couple thou a year, max.

2. Drill a hole in the slave housing for the spring, even though it looks a bit ghetto.

3. Fabricate a bracket for the spring as you suggested, Carl.

Hmm.

[a7dz]

I have been running my 70 with out the spring for five years now with out a problem.

[BoldUlysses]

Thanks Jim. I'm not going to put the spring on. I'll only be driving it for a month or two before it gets parked for the full-on down-to-the-metal restoration, so that's when I'll come up with a permanent solution to the spring "problem" (if it even is a problem).

[240260280z]

You could make a little bracket ...

FWIW,

Carl B.

Thanks for the great idea Carl, I just applied it to the Jan '71 I am restoring. In my situation I expanded on your idea. I simply used an engine lift-point head bracket (the longer one with the twist) and connected it to one of the M10 bolts that fastens the transmission to it's front cover plate (next to the slave). Perfect location and fit without having to fabricate. I'll take a picture the next time I am back at it.

I guess I could even fab a plastic "strake" to protect the slave from debris and water if I was OCD or racing

Edited June 2, 2012 by Blue