BUP

iTrader: (9)

really need to know the whole steering set up because at this point and time its a dart throwing contest .plus the outdrive set up - do you have an extension box ?

Also the other side of the coin for resistance is the higher you trim up the outdrive the further out of the water the drive / bullet comes up out of the water so hence less resistance against the steering components.

Do you have a power steering cooler and if so is it big enough in size for proper cooling ? If no pwr steering cooler you need one and the correct size for your set up.

Put Away Wet

The boat is a stock 425hp HO (other than the headers) with a bravo 1, no added on hydraulics. The problem started last summer with a Mercury factory pump. I'm not trimming any where near as high as I have the last 7 years with this boat. After the pump change last year it had the same problem. I don't have any fluid leaks and all fluid levels look good. When I'm running about 4800rpm and I'm trimming up the steering gets extremely tough to turn when I bump the trim up just below half on my gauge. When I bump it back down, the power steering works like it should (I don't think it's a RPM issue).
I don't know I'm at a loss. This weekend I'm going to look close for something that interferes with pump lines when trimmed. Other than that looks like I may have to bite the bullet and take it to my dealer.
Thanks for all the responses.

Falcon

HIgher trim, higher steering load, maybe it is maxed out on assist pressure. Probably turns easy in one direction, but not the other?

Cole2534

iTrader: (1)

Have you put a gauge on any of the hoses? One on the pump's discharge may show a pressure spike.

buck35

Is this a single or double ram set up? Cable or hydraulic helm? The devil is in the details.

BUP

iTrader: (9)

Like above asked is this a cable steering set up and stock actuator - (connected to inner transom assembly) set up ? if cable steering is this rack / pinion or rotary steering system ?

You mentioned changing out the steering pump / reservoir once before - did you clean out and flush all your power steering lines, power steering cooler and the actuator, You could have a restriction in the system

On your steering pump / reservoir is the correct relief / pressure valve installed ? Did you buy an auto unit ?

Young Performance

I'm interested in this one. He mentioned in post 12 that it is a stock Merc system with no add on or full hyd steering. He also mentioned that he changed the pump. My guess is that it's an automotive pump with the incorrect pressure relief valve.

buck35

?? Find anything

Put Away Wet

This problem started with the last power steering pump which was a Mercury pump. When I trim up it becomes extremely hard to steer (not pulling any one direction; just hard to turn). Then one time last year I was trimming up and it blew the front seal out of the pump. I did replace the pump with an automotive replacement ($40 vs $475 sounded like a good option). When I put in the auto pump the same problem is happening. I haven't blown the pump yet, but I'm not really running the boat up on much trim. I replaced the pressure release spring on the new pump with my Mercury one.
I guess I need to take take a closer look and see if anything is binding the fluid lines or the steering when trimmed up. I have good fluid level and no leaks.
My original concern is that the gimble has started to make noise and I was courious if it could be binding something at high trim causing the hard steering
I'm going out boating again today, I will look for something binding within the engine compartment.

buck35

Did you ever find any thing? Have you tried running on a hose trimmed up with some one steering side to side, or disconnecting it from power steering to see if drive or gimbal is the problem?