power steering

jp6

Cadet
Joined
Dec 17, 2003
Messages
29
Have mid 70's ford mercruiser v8. At cruising speed the steering seems fine but when I slow down It gets A lot harder to turn. The power steering belt seems pretty tight.Checked lines and fluid. Pulled return line off at tank while running and there is fluid pumping at idle but not a lot of pressure. Not sure how much there should be. Any suggestions would be appreciated.Thank you
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
Re: power steering

Try removing the steering cable from the power steering unit (at the back of the boat) and see if the steering wheel is still tight. If so, remove the cable from the helm unit and try again. If the wheel is not tight replace the cable, if it is, strip and repair the helm unit. If not, start checking for tightness elsewhere. Try unhooking the steering lever (the one that goes into the leg) and get outside the boat and see if the leg is stiff to move. The whole point of troubleshooting is to isolate each area and eliminate them individually. <br /><br />"Eliminate the possible and whatever is left, no matter how improbable, is the answer." Can't remember who said that.....<br /><br />Chris...........
 

jp6

Cadet
Joined
Dec 17, 2003
Messages
29
Re: power steering

thanks for the reply. I have checked the helm and the steering cable and they both move freely. Unhooked the outdrive moves very freely by hand. How can I tell if the pump is operating right?
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
Re: power steering

O.k. We have 3 possiblities.<br />1) Blocked/kinked hose. easy to check.<br />2) Faulty power steering cylinder. This model is rebuildable.<br />3) Faulty steering pump. Not rebuildable, just replacable.<br /><br />Have you removed the pressure line from the cylinder and check the pressure going to the cylinder? <br />
when I slow down It gets A lot harder to turn.
Would indicate a worn pump, but worth checking the 'cheaper' things first.<br /><br />Chris..........
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
Re: power steering

The high pressure side should be running around 1150-1250 psi and the low pressure (return) no more than 125 psi.
 

jp6

Cadet
Joined
Dec 17, 2003
Messages
29
Re: power steering

Thaks for the Info. I will check the pressure line going to the cylinder tommorow.
 

jp6

Cadet
Joined
Dec 17, 2003
Messages
29
Re: power steering

I took off the pressure line going to the control valve and let it run back into the resevoir. I dont have a gauge but at idle it is running out like water out of a faucet, maybe a liitle less and it does get stronger as you increase rpm's. I'm not sure if this is enough pressure. Is there a way to check the control valve and cylinder on or off the boat? And what is the difference between a auto power steering pump and a marine ps pump? they look very similar except the prices! Thanks for the help
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
Re: power steering

If you've run the thing with the pressure line off and haven't hosed the boat down with fluid, then it's looking like it's a worn pump :D . As far as I can work out you have already picked up the difference between the automotive and the marine. Just watch the direction of rotation and the mountings.<br /><br />Chris........
 
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