Hard Oil Line Purge Valve DIY... Success!

[whackit]

Hi All,

A friend of mine has those slick elephant racing lines with the built in purge valve. I always thought that this was a great feature and I had my lines out of the car...

Here's what I did.

Get a Schrader valve body from your preffered source. It should be all brass and have a large base. I got a 1/4" one from Mcmaster for 2 bucks. Note that you will need to get a valve that is rated for fuel and the correct temperatures.



You need to mill it to fit your line. It goes on the line that goes around the jack receiver. I used a 3/4" grinding stone mounted in a drill press. First I cut off most of the threaded base with a die grinder. You should cut it at a slight angle as it goes on a slightly curved part of the pipe. I then used my drill press vice and the grinding stone to mill the curve in the base of the valve body. It is a pretty easy job to get it to fit correctly.




Once you have it fit you should remove the valve from the valve body. Clean both the pipe and and the valve body to a bright finish. I suppose you could solder the body to the pipe but I brazed it for the additional strength. You don't want to clamp the valve body to the pipe when you braze it. The heat will likely distort the valve body if there is any pressure on it. Just stand the pipe up and support it. I brazed it on a step ladder with the pipe vertical so the valve body sat horizontally. I put a pretty good bead of braze around the base for support. Make sure that the nut to attach to the thermostat is above the valve (ask me how I figured that out) ! Flux and Braze!

Once the joint is cool pressure test by hooking it up to a tire inflator and seeing if there are any leaks. If there are none, CAREFULLY drill through the center of the valve body and though the pipe. A 1/8" hole is plenty. You want to make sure you don't mess up the valve sealing surface on the inside of the valve body. Remove any burrs from the inside of the pipe with a small file. Clean up joint, clean inside of valve body, replace Schrader valve, and flush pipe before reinstalling. Voila!

[azasadny]

Great work!

[LM3929]

any reason that you put it on the thermostat end, great Idea thanks.
lorne M.

[bkreigsr]

nice
so in theory, (or in reality - whichever), you can pressurize the line when you change oil and get a complete scavenge?
how much psi will be safe in the process?
will the oil above the valve, in the cooler, also come out?
do you have to heat the thermostat to get it to open and back-flush?
(do any of my questions make any sense?)

thanks

Bill K

[MT930]

Extremely Cool! Smart Method!

[whackit]

I am merely following the lead of the Elephant Racing oil lines. They are really beautiful, albeit pricey, hardware. it works by pushing oil all the way through the lines and back into the tank. The thermostat acts as a back flow behind the line so it is in effect a one way push through the entire cooler loop. So yes, theoretically it will evacuate all of the oil from the lines and the cooler. I imagine that any psi in the normal range would work, but in reality you need very little since you are applying the pressure to an unpressurized loop. I'm sure anything above 5 psi would do it.

Here's how it works, again, courtesy ER.



You can find the valve body I used here part number 80653k2. Note that it DOES NOT come with a fuel rated valve. You will need to get one from another source. I got mine from an AC dealer. I'm sure Chuck at Elephant would sell you one too. Again, thanks to ER for the original idea which I knocked off.

[whackit]

do you have to heat the thermostat to get it to open and back-flush?

no. it won't perform a 100% scavenge. But it gets a lot. If I drain my tank completely, then purge the line, at least 2 more quarts come out.

[Ferrino]

Bump for an awesome mod! Anyone else done this to the stock lines?

Here's a pic of the Elephant valve, for reference: