OMC 5.7 Power Steering

[ajkolar]

My 21' VIP with '88 OMC 5.7 steers very hard. I am sure there is a leak in the system somewhere, as I can refill the power steering pump and it seems to get better but gradually worse (as the fluid leaks out I am sure). <br /><br />Just wandering if these power steering pumps are marine specific, or if any automotive steering pump for a 350 SBC in the same year range will work? Also, is there one component that is most likley leaking (ie. usually pump, or usually ram mechanism)? What is the best way to diagnose this problem?<br /><br />Also, even when I fill the pump up to the correct level, the steering is far from perfect. It gets easier, but is pretty jerky as you turn. Is there another component I need to look at?<br /><br />I am reasonably mechanically inclined (I have swaped the engine in this boat) but just not real familiar with steering systems. Any help is greatly appreciated. Thanks!

 

[Bondo]

Re: OMC 5.7 Power Steering

I Don't do OMCs,........<br />But,.......<br />I'm guessing that they also use a P/S Cooler like everybody else........<br /><br />If you're leaking Oil,+ it's Not showing up in the Bilge,......<br />Chances are,..... Your P/S Cooler has some Internal Damage,+ is Leaking Into your cooling water.........<br />The P/S Cooler is Usually located In the In-coming waterline from the outdrive,.... Probably Somewhere Under the motor........<br /><br />Fix the Leak,+ Then you can purge the Nasties Out,+ it Should work Just Fine.......<br /><br /><br />BTW,...... Welcome to the forums here at iboats.com..................

 

[ajkolar]

Re: OMC 5.7 Power Steering

Yes I do have a P/S cooler. I suppose that could be pressure tested reasonably easy to test for leakage. I have always made sure to drain it for the winter, but also have had this problem since I bought the boat. Thanks for the advice, Bondo. It will be awhile before I can test this as my boat is stored in another state. <br /><br />In the meantime, anyone else have any ideas, or suggestions? Still wondering if these P/S pumps are marine only?

 

[Bondo]

Re: OMC 5.7 Power Steering

Still wondering if these P/S pumps are marine only?

Well,.......... There're Not Marine rated,........<br /><br />The Problem Is,.....<br />GM uses the same pump for about All of their P/S systems,.....<br />But,....<br />The Port configuration,+ Mounting points Are Different on Most All of them.......<br /><br />So,....If, By Chance,.. You Could find 1 off a car,.. that had All the Ports,+ Mounting points in Exactly the Right places,.... <br />Sure,.. Go for It.....<br /><br />But,......<br />Unless there's All that Leaked oil in the bilge, under the Pump,......<br />I Really Doubt it's your Issue.............

 

[DHPMARINE]

Re: OMC 5.7 Power Steering

Unless you see fluid coming out of the steering pump,it may not be your problem.I think you need to find where the fluid is going,and address that first.<br />I don't know about marine/auto pumps,but I would expect they are the same.Problem is the hoses and how they connect.And the pulley size and type.And as Bondo says,how they bolt up.<br /><br />DHP

 

[ajkolar]

Re: OMC 5.7 Power Steering

What about the actual assembly that actually moves the ram to turn the drive (sorry, not sure about the name)? Do those leak very often? If so, I suppose you would have a mess of P/S fluid underneath of it.<br /><br />I believe the previous owner replace the steering cable. He mentioned that he thought it was a little long. I would say there is a little excess, but not more than a foot and a half or so (just makes a bigger 90 degree turn in the back corner). Is it possible this could cause any problems? Seems like if it is hooked up at both ends, shouldn't matter to much?

 

[Don S]

Re: OMC 5.7 Power Steering

It really doesn't matter where others have had leaks, you need to find your leak.<br />You might try one of the pro's tricks. Wipe everything up nice and dry, then top off the fluid, and operate it and SEE where the fluid is coming from. May even have to get someone to operate the steering wheel while you watch. Then when you find where the fluid is leaking from. Fix that item. <br />The long cable shouldn't hurt anything unless it's binding. The PS cylinder needs to be free to move back and forth.

 

[ajkolar]

Re: OMC 5.7 Power Steering

Thanks for all the reply's. Don makes a great point, but with the boat in storage I'll have to wait, just trying to get as much info on what and where to look so I can dive in when the weather cooperates. Thanks again!

 

[rodbolt]

Re: OMC 5.7 Power Steering

on the OMC/Volvo acuators if the cable and acuator are not free to move its jerky. all must be able to swivel some.<br /> the power steering is a closed system, period. if you ever have to add fluid after the initial 20 hours it has a leak, period. its a closed system that is not supposed to use oil and the evaporation rate on ATF is low.<br /> so if your having to add fluid periodically you have a leak.