Power Steering Question

[Jim F]

I have an '89 Amberjack with twin 4.3 I/O's. The problem is that only the starboard engine has a power steering pump. The port engine has the brackets and pulley on the motor but no pump. I would like to keep the engine hours somewhat balanced but the auto-pilot does not like it when the power steering is off (tore up two actuators so far). I really want to get the other engine fitted with a pump but am a little at a loss on how to go about it. I think I will need some sort of check valves or a shuttle valve of some sort to keep from blowing all the oil out one or the other pumps.

Any ideas would be greatly appreciated. I don't want to spend the high dollar to replace the steering system with independent hydraulic steering since we are on a tight budget.

[1mainiac]

Honestly your only option is not going to go well price wise and that is to convert to HYD steering. Well another choice would be to use a electric power steering pump that was independant of either engine then it would not matter which engine was running. This might be a little cheaper than going to Hyd steering. A small snow plow pump will run your power assist steering just fine but will use 12v power all the time so you would need to make sure you have battery and charging system enough to handle it. By the time you purchase a second power steering pump and lines you are going to have a few bucks into it then you will need a diverter valve to seperate the 2 pumps and the valve must put one pump in bypass mode when both engines are running or the other pump will burn up. Lot of issues to cover here you don't need a lot of pressure the working pressure on a power steering system is fairly low most of them go into bypass at around 1900 psi you also don't need a lot of volume form the pump as the cylinder is fairly small. So a 1.5 gpm at 2000 psi pump would run the system just fine. The other option would be to put new pumps on both engines that use remote resevoirs the both pumps could draw off the same resevoir and all you would need is a check valve on the output of each pump and again there are many snowplow pumps that are engine driven that would do this as well. However the standard power steering pumps used on both boats and cars have a built in resevoir and can't be run in tandam.

[GLF]

Jim,

I have an 87 amberjack with the same set up. Let me know if you find a solution that works.

[1mainiac]

This pump will steer your boats all day long I would suggest a external psi bypass regulator cause I am not sure your steering system could handle the 2500 psi built in relief setting.

http://stores.daltonhydraulic.com/-strse-659/DC-power-unit%2C-hydraulic/Detail.bok

The real question is could your charging system and batteries handle it? My best guess is you would be adding a 30 to 50 amp continous load. With a external regulator set around 1700 psi you would never see max load on the unit and it has enough volume to handle what the boats need.

[GLF]

My altenator only puts out 55 amps.

[Jim F]

Thanks for all the good ideas. I think I am going to try a power steering pump out of a van with an external reservoir on each engine. I'll try using one tank to feed both pumps and that way it should not matter which pump is supplying the load while both engines are running. I will need a check valve in each pressure line to prevent back flow when operating with only one engine. I'll let you know how it works out and possibly have pictures in a week or two.

[1mainiac]

Jim remember you will have to set up both pumps the same way also plan on a larger resevoir tank to supply both pumps and to help reduce the heat as 3 or 4 gallon res would help cause when you are running on both engines the pumps will be in bypass mode at full flow all the way in so can build up some extra heat. I forgot about the vans having a remote resevoir another issue is to make sure your check valves can handle the flow from the pumps at full throttle. Automotive pumps are optimized to work between 800 and 2500 rpm so long runs at 3400 were not in their design plan they will do it fine but will have a lot of flow so a bigger tank would help. One of the other reasons I mentioned the engine driven plow pumps is that most of them came with a electric clutch like a air conditioner pump then you could just have a port or starboard slector as to which pump you ran and not have to deal with 2 pumps on at the same time ever.

[Jim F]

Thanks for the heads up on the heat issue. Having thought about this a bit I may put a solenoid valve across one of the pumps shorting the outlet to inlet so that when we are running both engines one pump we be completely bypassed and not going over a relief valve which generates a lot of heat in the oil. I am looking forward to getting this issue resolved one way or the other and will keep you all posted as to my progress.