I have been wrenching on power steering equipped modern cars for the last 20 years but I am stumped on this one. Of course it had to be a system on a custom that we built right? So here's the issue: Start the engine. PS is quiet for a minute then it becomes airated and begins to make noise. When it is quiet it has good assist and you can't really hear any straining at all. Let it run a minute or so and it starts to worsen to the point where you feel shutter in the wheel and noise becomes very loud. Even while driving you can hear it over the rest of the rattles and such. I have no external leaks. I pressurized the hoses and rack with shop air and sprayed soapy water (tire leak detector stuff) on the hoses and connections as well as all over the rack and see no leaks. I also did the same from the return fitting on the reservoir to the pump output fitting. Also no leaks found. I did the normal turning the wheel pin to pin a bunch then start and shut off, check level etc. I tried to drive it out. I tried applying a vacuum to the reservoir to "boil out" the air. All lead to no improvements. I know it's ingesting air somehow but I am stumped as to where it could be doing that from. Any other methods of diagnosis are welcomed. System info: -Speedway gen2 pump. With the pulley they offer for it (6" diameter) -Napa rack (# crosses to a '85 cougar) -3/8 stainless steel tubing from the pump to about 12" from the rack connection then though flexible hoses I had made at a local hose place. They connect to the rack using the -6 an adapters from speedway. The joints are also -6 connections. return line has a similar length of flexible hose then 3/8 stainless tubing up to the reservoir connected through a 6" rubber hose (as most other PS systems are done) -feed hose to the pump is 5/8" ID. It is not collapsing. I even put a spring in it to be sure. -All the connections were air/soapy mix checked for leaks. -Reservoir holds 8-10 oz of fluid. The bottom of it is higher than the top of the pump. -I have replaced the rack with the same brand thinking that was the issue but it continued. -I have tried the flow restrictor 2gpm and I have tried to shim the pressure valve. Both do nothing. -I spoke to borgeson about the pumps and they say that the gen2 and this rack work fine together and that even over pressure will not cause air in the fluid. They are sure there is air getting in on the return side but I can't find where. Anybody out there ever have an issue like this and what the hell am I doing wrong? I love manual steering more and more everyday.
im not familiar with the pump, but you mentioned feed hose. this is about the only thing i have seen cause the problem. as a truck mechanic almost 100% of the problems are suction hose related. i would: 1. closely inspect the pump suction hose for small cracks around the clamps, or even try a new hose 2. have you tried running it without a cap on the resevoir? 3. try a new pump glancing through my eaton hydraulics book beside the shop computer here the causes they list are suction hose defect, pump inlet restriction, oil temperature above rated listing (which i doubt happens within a couple minutes of running) and oil below rated viscosity.
This just happens on some cars. I have had similar happen on a 33 Ford I did last year. 700 Saginaw box and a Hydroboost with a Saginaw "canned ham" ps pump. Foamed up like crazy. Best thing to do is turn the rack full lock, hold it for a sec. Then turn it to the opposite lock, hold it for a sec. Return it to center and shut the car off and wait about 20 minutes or so, then repeat. There is air trapped in the rack and it won't come out until you cycle it out.
TRIED eLPOLACKO'S bleeding method. 12 cycles. 20-60 mins apart. No good. Still ingesting air. I tried 3 different fluids already. ATF and 2 PS fluids. Manufacturer states "No ATF" then when I opened the caps on the parts ATF came out. ATF? WTF? Pulled the hard line sections off for a closer look and put shop air in them and found no leaks with the soapy water. I am going to rework the reservoir fill tube to An -10 fittings and run a new AN fitting equipped short hose between them. Also gonna go up a bit larger on the reservoir? I have a new pump coming so I am gonna do that too since it's off already and kind of involved in the mix. After that it's a new set of lines I guess. I'll hear any thoughts no matter what they may be. And a huge thanks for the offered help.
when bleeding the air out by turning the wheel lock to lock, the wheels should be off the ground to lessen the load on the system. The air will bleed from the system much better this way. Hope you get it sorted out.
Kind of sounds like the problem that we have on GMC Acadias and Chevy Traverse, they are very difficult to bleed air out of the system. I use an Air Lift suction device that is really made to bleed cooling systems but works really well on these p/s systems. P/S fluid is a lot harder to bleed as well since it is a thicker viscosity than ATF.
My friends o/t Tacoma did the same after some genius pulled out the screen in the reservoir which is cylindrical in shape, the fluid would form a vortex then aerate the system, I noted the direction of the vortex and fed a cut spiraled hose clamp to baffle it, havent heared a growl since. Hope this helps!
sounds like your resevoir may be too small and the pump is ingesting a small amount of fluid and over time like you state (20 minutes) you get this issue. i would try a larger reservoir and re-bleed the system, it could be a kaked rack,if a seal is toast or the preload is off it could cause this type of issue also,an internal lip seal could be folded over and allowing some air in or the fluid to "flow" and "spill" into cavities its not supposed to and cavitate and get air in it. i have never had luck with "big box" rebuilds, racks, alternators,starters etc. try the bigger reservoir first and then my next would be the rack,it should have warranty.
X2. Used to do alot of rack and pinion and hydroboost conversions at a shop I worked at. We would leave the car on the lift with the front wheels off the ground, fire the car up, and slowly cycle the steering back and forth a few times, then let it sit. Also had to put a baffle on the return to the can on one of these set ups. It helped keep the returning fluid from foaming up the reservoir.
How are your hoses routed? Do they go higher than the pump? I've seen hoses routed above the pump body trap a bit of air and they are a BITCH to bleed that bit of air out. As others have said, try turning the wheel lock to lock several (15-20) times with the front wheels off the ground and the engine off. Then turn the wheel lock to lock and hold it on the stops several more times with the engine running (front wheels still in the air). Then put weight on the front wheels and see if the problem's still there. --Disclaimer-- The above is BMW's bleeding procedure for the E38 7 series. But I've worked on a lot of American stuff that likes to puke fluid all over the floor if you crank the wheel with the engine off. So turn your wheel slowly to avoid this!
Thanks for all the input. No lines run above the bottom of the reservoir except the last 5 inches of the return. I have tried all those bleed techniques already multiple times. I really hope it is something in the reservoir. It's a canister style that we made. I just copied an aftermarket one but I wanted it to look more fitting on the 8BA flathead so I made it in steel instead of Aluminum billet. Same reason I wanted to avoid braided steel hose and opted for clamped hoses. I made the return angled down and to the side so the returning fluid wouldn't splash into the pool so badly but I looked at a lot of factory ones this week and some of the returns are below the fluid level. Maybe that is causing it? No idea for sure but since I'm going to increase the size I am going to screen and baffle that and lower the fitting to below the fluid level too. I guess I'm gonna learn some R&D theory here huh? Damn! That stuff is expensive!
Old thread, but if you're still out there, what was the resolution? I have a similar issue going on, trying to track it down. 4th pump, 3rd rack, 3rd set of hoses, 3rd reservoir, many fluid changes, different bleeding techniques. Same R&P I have used dozens of times in cars, March (Tuff Stuff) pumps, never seen anything like it. Ugh.
If that pump is the small compact GM pump with external reservoir the pressure is too high for Ford R&P. A restrictor valve or additional shimming washers will reduce pressure.
Buy a stainless steel kitchen scrub pad and install it in the reservoir at the fluid inlet. It disrupts fluid flow enough to stop the huge pressure drop into the reservoir that aerates the fluid. Let the armchair scientists critique while you go to Wall-Mart and solve the problem in the parking lot like we did on Power Tour. We were scratching our heads with our new r&p systems on our Mopars when a kit car dude rolled up and dropped this solutuon on us. Sounded so crazy that we gave it a shot. He was gone like The Masked Man. Posted using the Full Custom H.A.M.B. App!
Hoses newly made? I once had a problem with a brand new high capacity PS pump and aerated fluid. After replacing the pump and getting the same results, I discovered that the fitting on my new pressure hose had been "over-crimped" and the pump was trying to force its high volume of fluid through a tiny opening in the crimped fitting. The pump was cavitating and the fluid that did get through was being aerated. A new hose made by someone who was more careful fixed the problem.
I had this same thing happen. It was the return line collapsing inside and restricting the flow. Everything looked fine from the outside. Hope it helps
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