Hot Rods Slave cylinder return spring

I am running a Chevy/ansen type brake/clutch reservoir with a factory style slave cylinder.
I was doing some searching and read a lot of replies with people not using springs to return the slave cylinder.
Without a return spring does the cylinder suck in all the way to keep release bearing off the clutch fingers?
Unrelated maybe but I’ll add my info 327, ST10 and McLeod street clutch.
I have it setup now so there’s a bit of free travel on the cylinder before the bearing touches. I had just assumed I should have a return spring to help keep it fully returned. But I was having trouble finding a spring that would work in my selection, if I use a spring are they usually fairly heavy?

Also does the slave just use dot 3 brake fluid?
Thanks.

 

I used a spring to retain the rod in the fork and return the slave. D

 

Something like a '40 Ford brake pedal spring works good.

 

Curious about the small piece of plywood by the filter Dennis? What is that doing there?

 

Man... you have good eyes.
I have no return spring on mine but now I want to add one.
And yes...DOT 3 fluid

 

Without a return spring you can, under certain circumstances, suck in air past the seals of the slave cylinder. A return spring keeps pressure on the slave piston as it is being sucked back into the slave body, when the clutch pedal is released. The spring also keeps the linkage from ratteling or falling out of position on the clutch arm.

 

Be careful that you don't use a too strong spring. Just enough to hold the push rod from rattling about. The pressure plate is your main return system. If the slave cylinders piston is pushed back more than it needs to you will find you need to pump the peddle to get it back each time you change gear. JW

 

The slave push rod should be adjusted so the slave piston is pushed all the way back by the spring when the throughout bearing has the correct gap of about 1/16" to 1/8" from the pressure plate fingers. The geometry of the linkage should be designed so that the clutch pedal cannot over push the fingers on the pressure plate.

 

Spacing my exhaust from my oil filter until I got it welded. D

 

Here’s how I have it setup.
I pushed the piston into the bore as far as it would go, then set my 1/16th free travel for the bearing.
I guess I would have to worry about over travel like this eh?
I haven’t played with anything like this so it’s a bit foreign to me.
It is fully adjustable and I used a heim joint on the fork.
It looks closer to the exhaust in the pic than it is, but I do plan on wrapping exhaust to keep heat away from cylinder anyway.

 

I use this slave in my kit for the T5 to Flathead kit and I just get a spring from the local Auto Value under the Help line. Just right, not to strong and returns the cylinder all the way back.