Working on the T was wondering if you need to run a check valve if the master cylinder is below the slave cylinder.If so what p.s.i would i use thanks for the info.
I've never encountered this situation but you may want to try it w/out one and if you have any problems use a 2# r.p.v.
don't think ya wanna hold presure, ya just don't want it to drain back out of the master. May need a remote resivor mouted higher.
As Janis Joplin said at the end of he rendition of "Lord won't you buy me a Mercedes Benz......... "That's It"!
We've never run a check valve in any of the frame mounted hydraulic set ups we have done over the years. It has never been a problem. This was with wilwood or tilton masters with matching external slaves.
if youre master doesent have one built in You may need one. Could the slave drain back and overflow the master? Not a residual a check.
The old Chevy truck dual master cylinder that actuated both the clutch and brake had a residual valve only on the brake side. Of course the way Chevrolet used it, the left side was the brake. So when using it on an Ansen swinging pedal set up, you needed to move the internal residual valve to the clutch side where it became the brake side.
Holding pressure in the system has the potential to hold the throwout against the clutch and wear out the bearing. The system shouldn't drain back because it is a sealed system.
My only concern would be the slave cylinder pulling in and holding air over time being that it sits the highest and I was assuming an r.p.v. might retain just enough pressure to prevent that. I was also thinking there is a return spring on the fork or built in (shaft mounted) that may be able to override it. A remote reservoir may cancel this out via gravity but then again the slave cylinder line still has to go uphill. A lot of sand rails are running around w/basically the same setup just fine w/out an r.p.v. (as far as I know) so yours probably will too. Just thought I'd explain my first post.
Sand rails don't get many miles and don't drive on the street. If the resivor is higher then the rest of the system it wont drain back. I have my brake master under the floor and the front disc caliper is higher then the master without residual valve and there is no drain back on it.
From the ECI Brakes web site Gary "[FONT=Verdana, Arial, Helvetica]2 PSI Valves[/FONT][FONT=Verdana, Arial, Helvetica] - These valves are used in a disc brake system only and are required when the master cylinder is at, or below, the height of the calipers. It's purpose is to act as an anti-siphon valve preventing the brake fluid from siphoning back into the master cylinder when the brake pedal is released. Even if the master cylinder is even or slightly above the calipers, put one in anyway. If you don't and you park on a hill, fluid will siphon! These valves are cheap insurance - put them in!"[/FONT]
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