We need some information about an oil pressure relief valve.for a pressurized oil system on a model T.
My friend (Reed “Rattler” Olsen who does not have internet) is building an engine for a Speedster. He plans on having a Chevrolet Head, Multiple Carburetors, Headers, etc.
Rattler has mounted a Volkswagen Oil Pump at the rear end of the cam. He is planning on running oil lines to an external oil filter and pressure-regulating valve outside the engine. He will return the oil back inside the pan to the main caps.
Does any one know where to get an oil pressure-regulating valve?
Thanks in advance for your help!
Look at www.McMaster.com
Wow, how much pressure does a VW pump make?
Eric- contact me off line.
Doug- a VW pump is a positive displacment pump- the pressure will climb until something gives, blows out or breaks- that's why you need a relief valve.
Ah, I see.
They're simple enough to make. You could start with a 1/4 or 3/8" brass Tee. Add a ball, spring and adjusting plug with holes. The ball seals the relief port until pressure over comes the spring. As soon as pressure drops, the ball seals the relief port again.
You may have to experiment with the spring pressure but I would start just under your desired pressure and use small holes in the adjusting plug. Some constant bleed will keep the valve from "screeching". (Rapid opening/closing)
I forgot to show in the drawing but this type of valve will usually have a stop pin inside the spring. It's part of the plug. The pin will limit the ball movement and keep the spring centered over the ball.
Do you really need one?? Is pressure needed or is flow needed? If you plumb a oil filter with 1/4" going in and 3/8" going out will there be pressure or flow? Will a gear driven oil pump do any better than the large hogshead oil scoop? Would the 1/2" line feed 4 1/8" lines/jets aimed at the mains/rods?? What is the GPM of the V_Dub pump?? Bud.
He's running the oil lines to the main caps where there is bound to be a resistance to flow, (unless the bearings are shot). As Dan explained, the VW pump will make more pressure & volume than the system can handle, unless there's a "blow off" to keep things regulated. If he were just making an "oil mover" to get the oil through a filter then dump it back into the engine then no, he probably wouldn't need a regulator.
If you look at the San Diego T Club web site (www.mtfcsd.com) you can see a rather simple oil pressure system. It uses the early VW oil pump which is about 1" deep, the later versions are too deep and more difficult to install. The oil pressure relief valve is a length of Al rod about 1" diameter, drilled to fit a 3/8" ball bearing and held with a spring. The pressure is set to break at 28psi, roughly the same as the early (1950-66) VW's.
I want to thank everyone who took the time to answer my questions.
I have printed all of these replies and have given them to Rattler.
Tony I have sent you an e-mail to your email address listed with MTFCA.
The VW pump that Rattler has installed on his block hits the flywheel. In fact I would need to remove about 3/8” from the flywheel to clear the pump. Is it possible that he has a later model VW pump that Tony talks about in his reply?
Thanks again to everyone!! While I am just the messenger, I am learning a lot from these threads.