Join Date: Sep 2000
My 68 has a check valve,I it is essential,if you want your doors to open quickly,after you start the car.I'm using the repro canisters and relay valve,they work flawlessly(if you take out the I am an idiot factor)The relay valve is just a spool valve connected to a rubber diaphram on top.The top port is to the rear of the canister,my hose is green.The rear of the canister pulls the doors closed When vacuum is supplied to the diaphram,it pulls the spool valve up,connecting the supply port(center) to the top port.You could check the relay valve for a vacuum leak by sucking on the center port,and covering the lower port.If it holds vacuum,it doesn't leak.Pull a vacuum on the upper diaphram,this will pull the spool valve up,connecting the center and top port.Try the same test,if it holds vacuum,it's good. This is really a simple system,easy to test,if you understand how it works. I took apart my origional relay valve,and sealed it up by "shimming" up the lip seal inside.It worked great,didn't leak anymore,to bad the canister on the right side leaked,and the hose clamp I used to clamp the valve back together was ugly.The "hole" on the bottom of the valve needs to be there,it is ableed to atmosphere,without it the system wont work properly. You can use the check valve for a 69,it is installed near the master cyl. The hose that is t'd into the supply line (tank to valve) will go to the check valve,instead of the Tee.Just run a straight piece of hose (no Tee) from the tank to the valve.
68 z28 ,68 rs 327 ,73 454 vette, 2 goofy kids
[This message has been edited by dale68z (edited 04-29-2001).]