After attending several open track events, I noticed many people were having problems with their power steering systems. Not only were stock type systems having problems overheating, some remote tank systems were running very hot, seeing foam in the tank, or had noise problems.
Below is Carl Casanova's stock type 67 pump. While running at Buttonwillow the pump got hot enough to soften the solder holding the pump neck onto the main reservoir! The pump was cooked inside and had to be rebuilt. Several other cars had non-working power steering by the end of the day, they removed the pump belts and drove home with no steering assist.
I saw one pump with a piece of 1.25" diameter hose extending the stock reservoir neck up about a foot, this pump still overheated due to no cooler and sprayed fluid all over the engine, lucky there was no fire. I believe the fluid got so hot it boiled, or foamed so much it sprayed out of the raised cap.
I'd been warned about foaming problems when I bought a Sweet PS kit, it came with a late model "small" pump, mounting bracket, and remote tank. The tank was reported to have foaming problems and a KSE tank was recomended, since I had two of these tanks and the tools to change them around, I installed the "bad" Sweet tank on my wife's 73 Camaro as a test.
Below is the foaming problem of the Sweet tank. This was after just a fiew miles of street driving!
The Sweet tank has a -6 return line near the top, just inside the tank is an aluminum cap over the return fitting, the cap has a hole in the side of it and the fluid must make a ninety degree turn around a very sharp corner, then it swirls around the tank to cool. Another thing I noticed is the screw-on cap is sealed with an O ring, but there is not a vent hole in the cap! While this may prevent a spill, it is not a good way to set up any hydraulic system, the tank should be vented. I drilled a tiny hole in the cap.
A cooler is a good idea, we are using a small auto trans cooler on the 73 ps system.
I removed the -10 outlet fitting, it was a steel hydraulic fitting not an aircraft fitting. The hole in the center was very small compared to the aircraft hose that connects to it. I believe this restriction caused extra suction and contributed to the foaming along with the lousy return fitting.
Below are two tank outlet fittings, the small ID fitting was opened up to 63/64" to increase flow and reduce suction. Right, is the back side of the fittings, I radiused the edge after boring it out.
I made a new return fitting, it's shaped inside like a reversed fire hose nozzle, it's tapered but it get's larger as it goes, not smaller. I also angled it upward a little to make any bubbles rise to the top, and positioned it lower on the tank so it wouldn't splash up on the cap, and would stay submerged if the tank level fell. The fitting is angled on a tangent to the tank to swirl the fluid against the tank sides, but it is not a severe swirl. I welded shut the old upper return hole.
These mods plus the cooler work great on the street, no more foam! I
won't know for sure this is the perfect setup for track use, but it
should work well. The pump used to groan just a little after a mile
or so of driving, now it stays quiet and the fluid is clear.