Double Aught

I posted this in another forum, chevytalk and only got a couple of replies. The car isn't a Corvette, but my Impala falls in the C3 year catagory. 68 Impala SS restomod. Has a 94 Lt1 drivetrain. I installed a quick ratio PS box and am using the PS pump from the LT1. I also installed a PSC 1200 PSI valve that allows the lower pressure LT1 pump to create the pressure needed for the box to function properly. Now the issue. We all know when we have air in our steering system. I have bled the system twice, wheels off the ground, turning the wheel lock to lock, over twenty times, with a friend observing the pump reservoir, making sure it doesn't run out of fluid. I am using fluid recommended for the Impala. Yesterday, took her out for a spin and boom, the moaning, "air in the system" came back. Got back home, futz around a bit, started her back up and it was like nothing happened. No moaning, no noise. Normal. Went for another drive and as soon as I pulled into my driveway, it started again. This is driving me nuts. Any suggestions and has anyone else experienced this off and on problem with their power steering system? Is there a way to pressure test a power steering system to detect hidden leaks in hoses? I would assume that if a hose had an issue and was leaking fluid and drawing air in to the system, that leak would be pronounced. Thanks for any assistance.

ratflinger

Hmm, PS pump off a V8 Impala?

Double Aught

No, the pump is a stock 94 LT1 PS pump going into a stock 68 steering box.

CA-Legal-Vette

Just a guess, but I’d make sure that the connections were tight and appropriate, especially where old meets new. Guessing that you had to cobble this together. Sounds like you’re drawing air in so check the input at the pump first.

Double Aught

The two main hoses were made new and the only hose that is old is the hose from the remote reservoir to the pump. I am going to check everything again this weekend and I have a replacement reservoir hose I'll be putting on.

jackson

Yup... chevy's been making them for about 2-3 years maybe more … like the now-discontinued SS, but rather elegant … with LS power & RWD

Chevy got back in the police car business too... based on same sedan platform.. I never see em though.

lionelhutz

Swap the stock valve back into the pump and see if the problem goes away..

Double Aught

Well, I bled the system today and everything sounds and drives like normal. While the car was in the air, I did notice the return line was wet. Not dripping on the ground, but there was what appeared to be oil on the line itself. that hose was not new, just the connections at both ends. That hose is a two piece, one piece coming off the pump (the LT1 pump)and the other piece going into the steering box (the original impala piece). I am thinking air may be being drawn in where the two hoses are connected. I used a barbed brass fitting to connect the two, with a crimped hose clamp on one and a spring clamp on the other. I think I will replace the spring clamp with a crimped one and observe if the problem reappears. If it does, I'll have the hose replaced altogether.

lionelhutz

If air did mange to get drawn into the return line it would just return the the reservoir where it can exit the fluid.

The return line isn't under vacuum so it should never suck in air.

'75

Is the return line entering the reservoir below the fluid level, if close to or above the fluid level it could be causing aeration/foaming of the fluid.

Double Aught

yes it comes in below the fluid level. (i think. l will look at it again tonight)