Dismiss Notice

Welcome To CK5!

Registering is free and easy! Hope to see you on the forums soon.

Score a FREE t-shirt and membership sticker when you sign up for a Premium Membership and choose the recurring plan.

Need Help with Hydro Assist!!!!! UPDATED

Discussion in 'The Garage' started by Russ, Mar 13, 2004.

  1. Russ

    Russ 1/2 ton status

    Joined:
    Feb 17, 2000
    Posts:
    509
    Likes Received:
    0
    Location:
    Summerdale AL
    I just installed my fifth power steering pump in the last few months. Third in the last week. I get a really loud whine starting at about 2200 RPM and getting louder as the RPM's go up.
    I am running a new tapped gearbox, a 2" Northern Tool variety ram, and a stock pump with the valve modifications done according to the WTO website.
    When I initially set this up it was fairly quiet, but I killed the original pump due to low fluid volume. I since modified my reservoir by welding a cap with 3/4 nipple to the top of it and mounted a remote reservoir above it to increase the volume. I am no longer having fluid volume issues, but I get the same loud whine in the last three pumps, 2 of them rebuilds and one brand new. I dont understand why it is whining like it is, I have rechecked and tightened all fittings to ensure there is no air leaks, and the fluid is not frothy like it would be if it had air in it.
    If anyone else has had any problems like this I would appreciate some advise. I tried emailing Matt at WTO, but have gotten no reply.
    Thanks,

    Russ


    Update 14 March:
    I pulled the pump out again and reinstalled it with another valve that I drilled out to 3/16ths. Larger than stock, but smaller than what I had drilled out the first one. Test drove it and had great steering response, but the whine was still there. It was only about half as loud as before and had moved up to about 2700 RPM's.

    I then took it out again and put it back together with a completely stock valve. Steering is a lot stiffer, definitely still manageable though, even at idle. Best news is that the whine is completely gone. Jimmy88 was right on with the outgoing fluid and incoming fluid theory. I appreciate everyone's help.

    Russ
     
  2. FWP

    FWP CRS

    Joined:
    Oct 11, 2000
    Posts:
    3,845
    Likes Received:
    3
    Location:
    Prescott Valley, AZ
    Re: Need Help with Hydro Assist!!!!!

    Where are you getting your pumps? I remember reading a post here somwhere that people were having bad luck with Autozone pumps. I have a new pump from Checker, with the 1-1/2 ram and a ps cooler, no problems from the pump yet. been hydro for about 6 months now.
     
  3. az-k5

    az-k5 1/2 ton status

    Joined:
    Oct 15, 2003
    Posts:
    2,774
    Likes Received:
    0
    Location:
    Phoenix AZ
    Re: Need Help with Hydro Assist!!!!!

    Any chance that the tube between the reservoir and the pump is causing a little restriction? (I can't picture a 3/4" fitting in my head to compare) That tube could work fine but as RPM's go up so does flow rate. If the velocity is too high the pressure inside the line becomes really low and can even collapse (slight possibility but not likely). I am probably just barkin' up the wrong tree though.
     
  4. jimmy88

    jimmy88 1/2 ton status

    Joined:
    Feb 17, 2002
    Posts:
    351
    Likes Received:
    0
    Location:
    Detroit, MI area
    Re: Need Help with Hydro Assist!!!!!

    The WTO mods are to increase flow at idle and low rpm, maybe allow too much flow at higher speeds? Remember the high school science experiment where water boils at room temperature when a vacuum pump lowers the air pressure in the container with the water? That is what can happen inside the pump if the suction side can't keep up with the flow. Were you running the modified valve in all the pumps? Why not try putting the stock valve setup back in and see if the noise stops (that is if cavitation hasn't damaged the pump already). http://www.insidersecretstohydraulics.com/newsletters/issue03.html
     
  5. Russ

    Russ 1/2 ton status

    Joined:
    Feb 17, 2000
    Posts:
    509
    Likes Received:
    0
    Location:
    Summerdale AL
    Re: Need Help with Hydro Assist!!!!!

    I got one rebuilt pump from Autozone, one from Napa, and one brandynew one from GM. They all have the exact same whine starting at about 2200 RPM. I even disconnected my ram and still had the whine.

    I used a remote reservoir and the hose from a hydroboost system. It is a pretty stout hose. I watched in the reservoir as I revved the engine and everything seemed to be working properly. The only improvement that I could think of to the remote reservoir would be to add a fitting to it and route the return line directly to the reservoir rather than to the back of the pump.

    Keep the ideas coming, I am at a loss as to what to do.

    Is there anybody else out there using a big 2" ram like this one I got from Northern Tool? If so are you having any problems with a stock pump keeping up?
    Thanks for the help.

    Russ
     
  6. Russ

    Russ 1/2 ton status

    Joined:
    Feb 17, 2000
    Posts:
    509
    Likes Received:
    0
    Location:
    Summerdale AL
    Re: Need Help with Hydro Assist!!!!!

    I couldn't get to the link you posted, but yes, I was running the modified valve in all the pumps. Unfortunately high school science was about 25 years ago, and I didn't really pay as much attention at the time as I should have. You may be on to something there though. As much as I hate to pull the pump apart again for the fourth time in one week, I will try putting an unmodified valve back in and see what happens.
    Thanks,

    Russ
     
  7. big pappa b

    big pappa b 3/4 ton status

    Joined:
    Jan 3, 2003
    Posts:
    6,328
    Likes Received:
    0
    Location:
    Falcon, Colorado
    Re: Need Help with Hydro Assist!!!!!

    Are you 100% sure it's the PS pump making the noise? /forums/images/graemlins/dunno.gif
     
  8. Russ

    Russ 1/2 ton status

    Joined:
    Feb 17, 2000
    Posts:
    509
    Likes Received:
    0
    Location:
    Summerdale AL
    Re: Need Help with Hydro Assist!!!!!

    I am sure, at first I thought it may be the alternator as they share the same bracket and I couldn't tell precisely where the noise was coming from. But I had a short belt and ran it just from the balancer pulley to the P/S pump and it still made the noise.

    Russ
     
  9. scoutillac

    scoutillac 1/2 ton status

    Joined:
    Feb 24, 2004
    Posts:
    423
    Likes Received:
    0
    Location:
    Spokane, Wa.
    Re: Need Help with Hydro Assist!!!!!

    I thought mine was the PS pump too. It turns out it was the A/C clutch going out. Not one problem since. I need to modify my pump. The flow sucks at low RPM's. It worked great at the ORV park today. /forums/images/graemlins/peace.gif
     
  10. BlueBlazer

    BlueBlazer 1/2 ton status

    Joined:
    Feb 15, 2001
    Posts:
    1,940
    Likes Received:
    0
    Re: Need Help with Hydro Assist!!!!!

    First of all, do you need a 2" ram? That thing needs a lot of volume in addition to what the box needs, and it may be that you are cavitating the pump since its using up all of the reservoir volume thus sucking in air? Do you have an air leak somewhere on your inlet side on this reservoir you made up or the line going to the pump?
     
  11. Russ

    Russ 1/2 ton status

    Joined:
    Feb 17, 2000
    Posts:
    509
    Likes Received:
    0
    Location:
    Summerdale AL
    Re: Need Help with Hydro Assist!!!!!

    I probably didn't need a 2" ram, but it was fairly inexpensive at Northern Tool and fit my budget for putting together a system. I watched the fluid level in the reservoir while I revved the engine and the fluid level is not depleting. My remote reservoir is a stock GM hydroboost reservoir and hose and my modified can that I have it running into does not appear to be sucking in any air.
    I am leaning towards the cavitation thing though. But I do not understand why it would cavitate when it has plenty of fluid volume. I obviously do not know enough about hydraulics.
    Thanks,

    Russ
     
  12. BlueBlazer

    BlueBlazer 1/2 ton status

    Joined:
    Feb 15, 2001
    Posts:
    1,940
    Likes Received:
    0
    Re: Need Help with Hydro Assist!!!!!

    Does it whine just when turning or always?
     
  13. jimmy88

    jimmy88 1/2 ton status

    Joined:
    Feb 17, 2002
    Posts:
    351
    Likes Received:
    0
    Location:
    Detroit, MI area
    Re: Need Help with Hydro Assist!!!!!

    I'm used to centrifugal pumps and have to switch mental gears /forums/images/graemlins/rolleyes.gif to think about positive displacement pumps like the vane type power steering pump. I got the first link doing a search on google looking for hydraulic pump cavitation. Here is another link that should work: http://www.findarticles.com/cf_dls/m0BQH/2_46/98032270/p1/article.jhtml
     
  14. Russ

    Russ 1/2 ton status

    Joined:
    Feb 17, 2000
    Posts:
    509
    Likes Received:
    0
    Location:
    Summerdale AL
    Re: Need Help with Hydro Assist!!!!!

    It whines starting right around 2200 RPM's and it makes no difference in intensity if I am sitting still or turning the wheels. It gets louder the faster the RPM's. It is screaming pretty loud by the time I hit 3K. All three pumps make identical noise.

    Russ
     
  15. Russ

    Russ 1/2 ton status

    Joined:
    Feb 17, 2000
    Posts:
    509
    Likes Received:
    0
    Location:
    Summerdale AL
    Re: Need Help with Hydro Assist!!!!!

    Thanks for the info. The return line is feeding right into the back of the pump and there is an abundance of fluid in the remote reservoir, so I don't really understand why there should be cavitation. It definitely seems to be though since it is speed related and works great up to 2k RPM's. Steering is very responsive even at idle.

    Russ
     
  16. jimmy88

    jimmy88 1/2 ton status

    Joined:
    Feb 17, 2002
    Posts:
    351
    Likes Received:
    0
    Location:
    Detroit, MI area
    Re: Need Help with Hydro Assist!!!!!

    Its where the oil goes into the pump that could be the problem in an excessive flow situation. Even if you have a swimming pool for a reservoir you can only suck out as much as the passage connecting to the pump cavity to the reservoir will allow. Try to suck more and vapor pockets will form in the oil and cavitation will result. Is there a hole or port on the back of the pump housing where oil from the reservoir is sucked through to get to where the pump vanes are?

    I don't know though. On a positive displacement pump the flow should depend on rpm and since you haven't changed the displacement of the cavities or pulley diameter the total flow out of the pump before the flow control/pressure relief valve should be the same as stock. That brings up the question of how the flow control and pressure relief valve assembly effect the pump operation. /forums/images/graemlins/thinking.gif
     
  17. BlueBlazer

    BlueBlazer 1/2 ton status

    Joined:
    Feb 15, 2001
    Posts:
    1,940
    Likes Received:
    0
    Re: Need Help with Hydro Assist!!!!!

    I may have missed this part, but have you put an unmodified relief valve or whatever you modified back in? Are you sure the whine isn't belt slippage?
     
  18. Russ

    Russ 1/2 ton status

    Joined:
    Feb 17, 2000
    Posts:
    509
    Likes Received:
    0
    Location:
    Summerdale AL
    Re: Need Help with Hydro Assist!!!!!

    I will have to try and disassemble one of the many extra power steering pumps that I have lying around here and see if I can tell where the suction port is for the pump. I don't know how I would tell if it is the right size in comparison to the outgoing pressure port though. I think what you are talking about could be what is going on with this system. I may have modified my valve a little too big. It works great at slow RPM's though!
    Thanks,

    Russ
     
  19. Russ

    Russ 1/2 ton status

    Joined:
    Feb 17, 2000
    Posts:
    509
    Likes Received:
    0
    Location:
    Summerdale AL
    Re: Need Help with Hydro Assist!!!!!

    I have not reinstalled an unmodified valve yet. I think that may be my next step. I did try a different belt and it still whined.
    Thanks,

    Russ
     
  20. Russ

    Russ 1/2 ton status

    Joined:
    Feb 17, 2000
    Posts:
    509
    Likes Received:
    0
    Location:
    Summerdale AL
    Re: Need Help with Hydro Assist!!!!!

    Updated at the top. Thanks for all the advise, it is working good now.

    Russ
     

Share This Page