Imco Hydraulic Steering Help
 

I have a helm to dual ram set up on the Activator. That is loosing pressure from some where. The issue started last year while causing around 70 MPH all of the sudden the boat just went left. And lost all control in the wheel for about 10 seconds. Then straightened it's self back out. That was the last time we ran it for the year and parked it for the winter. Getting it around this spring we bled the system and we're able to get the air out but the boat continues to randomly just shoot left at any speed. Bled the system again over the weekend 10-15 full lock side to side turns and by noon today there was play side to side in the drive again. There are no signs of leaks. In the engine compartment or externally with the boat sitting or with the engine running. And all of the fittings are tight. Is there a way to pressure test the system with out the engine running so I can get a good look at everything and has anyone ever had issues with the systems sucking air? The resiviour is vented and kept about 1/2 full to alow any air to escape. Thanks for the help!!

Are you saying the fluid level is NOT going down? When you "Lost all control" was the steering wheel free spinning? When the unit has play side to side is this while the pump is running?

When it looses control the wheel locks up tight. The unit will have play side to side with the pump running unit you bleed the air back out of it again. And then it will hold solid with no play for about a day.

I don't know what the fix is, but it sounds scary. I would call IMCO or maybe Bob Teague for ideas. Doesn't sound like something that you want to be wrong about.

Is you boat a single engine? If yes prop torque would turn the boat left or right depending on propeller rotation if your system failed correct?
Have you looked at the helm for signs of a leak? I think the failure is there.
Each ram is a push pull device. It would take a failure of both rams wouldn't it for this to happen?
This is just FYI, I have maybe the same system and the instructions say to bleed the system with the engines off. Maybe thats what you did and i just misread your comment.
Very interested in what you find out.

I found a phone number for IMCO.
1.888.427.7436 Mon theu Fri 7:30 to 4.They are in NV.

You have to pinch off the return line to force all the fluid through the rams, if not the fluid takes the path of least resistance

Yes its a single engine 27' Activator That spins to the right with a SSM 5 drive. There are no external signs of leakage at the helm. Iv bleed it both ways with the engine running and with it off. And both times after about 24 hours of sitting the drive will have play in it again.If you bleed untill there is no play in the drive and no more air coming out of the resiviour breather and then run the boat immediately after it still randomly dose shoot to the left.

Thanks for the info. I will try this and update.

Have you checked the helm? It sounds like the helm has an internal leak that is not directing the fluid the correct way.

Sounds like the helm to me, too.

There's no signs of an external leak at the helm but haven't popped the cover off yet to check further. Is there anything specific I should be looking for when I do take the cover off?

When the problem showed up last year was it after you added fluid? Just wondering if you did add fluid if what you added is not compatible with what was in there? I know certain greases cant be mixed. They go from grease to soup. Might just need a flush and refill?

I don't know. It has been 40 years since I was in hydraulics/pneumatics class. I do know they have a series of valves and vanes, it is a pretty complicated design, and you likely would be better off to get a replacement. I would call IMCO to get the correct replacement. I really doubt they make it, they most likely buy it from Parker Hanifin. The part number is probably on yours and you can get them from any hydraulic supply house. They are a very common steering pump on fork lifts etc.

Thanks for all of the suggestions everyone! Took the boat to the ROPA Battleship Run this weekend. Back it into the water it wouldn't start. Threw in 2 new battery's and still no luck. Looks like I have a few new issues to figure out before coming back to the steering. B.O.A.T

Bring this thread back around as I now have more questions then answers on my steering issues. Turns out I have a latham marine steering system not imco. Once I figure out how to change the thread title I will. So I was still having issues where the steering would bleed all of the air out and be rock solid at the drive no movement at all side to side. After 12 hours or so there would be about an inch of play and it would progressively get worse as time goes on. Using some leak finder dye I figured out the bottom seal on the reseviour was leaking so I replaced the seal. Bled the whole system again and am still having issue. I can bled the air out but once the engine sits not running it looses pressure. I pulled my power steering pump off and noticed the inlet to the pump is a very loose push in AN fitting. Is there a reason the pump inlets aren't threaded? I understand there is just head pressure from the reseviour on that side of the pump but could a very loose fitting be causing air into the system?

https://cimg3.ibsrv.net/gimg/www.off...8882287319.jpg
https://cimg7.ibsrv.net/gimg/www.off...0d66f772e4.jpg

At the very least I would expect an o ring on that fitting. Would be a little tricky to machine the groove but possible.

The stock mercury version of that pump has a steel tube pressed in there and uses a hose & clamp