Hi. I have an IMCO add-on single ram hydraulic steering attached to a Bravo drive with the old type Saginaw control valve. When running the boat at higher speeds the boat does not always steer straight, it sometimes"meanders" slightly. My hypothesis is that it takes too long for the controlvalve to deliver the oil volumes needed by the external steering ram. The external ram probably needs a number of times more hydraulic oil than the internal ram to do its job. This brings the time for the reaction of the steering ram into dangerous levels. When the drive is pushed from the outside by the boat hitting a wave the responsetime is so long that the steering starts to oscillate. Has anyone else experienced this????

Let us know if the problem just started or if this is a new install.
I am not a expert on steering but do have a opinion. I doubt if your theory is right, the Saginaw valve should be able to push/Pull fluid in a equal amount. The travel of the ram may be effected but not the solid connection (in any position) to the ram.
I would look at air in the system or a problem with Gimbal housing can you move the outdrive around by hand?
Your description sounds very dangerous and I hope you are able to get this fixed without a lot of hassle.

I have the same system on my 25 Outlaw and do not see any play at speed. I have two different boats with the same setup and no problems to date. Are you losing any fluid?

Could it be your boat can not handle the high speed & you are chin walking?

I have that system on my 500EFI/26' Sonic, and the only problem I had was when I blew and external hydraulic line. Steers perfect.

i HAD A BOAT THAT DID THIS WITH SINGLE RAM AND IT WAS DUE TO SLOP IN THE GIMBLE AND THE PROP MOVINGTHE DRIVE ,I KNOW I'M USING CAPS BUT TAZ SAID IT WAS O'K' SO ITS EASIER ,ANYWAY I KNOW IT SHOULD NOT DO THIS BUT IT DID UNTIL WE TIGHTENED EVERTHING UP AND ADDED A CYL FOR STRENGHT ,HOPE THIS HELPS YOU

Thanks for your input. A few more clues;

1.The drive can relatively easy be moved from the outside with the engine running. When I did that the wheel was free to move (and so it did)
2.The "meandering" starts already at 30-40 mph if triggered by choppy water
3. There are no oil leaks
4. It feels like there is a delay in the power assist. It is definitely not like steering a car
5. I think it has been like this ever since the installation of the IMCO ram which was about 100 engine hours ago .
6. The cable steering is a Morse rack and pinion system
7. The gimbal ring is new and there is very little play in the mechanical part of the steering, the drive can be moved maybe half an inch without the wheel turning

Is there a need to bleed the system ,other than moving the wheel from lock to lock? how?

I

I recently installed an Imco single ram system, but it refered to a Brazil valve instead of a saginaw valve in the instructions. The instructions said to "Turn the system from side to side and add fluid as needed, but if the drive was not rock solid after doing this excess air would have to be bled from the system. I think the only way to do that would be loosen one of the lines on the cylinder and watch for the fluid to run clear with no bubbles. I don't know if that is the exact way to bleed the system, and the instructions did not detail the procedure.

Hi. I have now done some further investigations and found that it is play in the mechanical part of the steering. The wheel can actually turn on half turn without the drive moving! The problem is the tiller arm not being firmly anchored to the gimbal ring. I have tried to tighten the nuts on the outside to 55 footpounds ,but no improvement. What should I do????

I am also quite amazed how it is possible to develop such a crappy design of a steeringsystem!? Why isnīt the tiller arm firmly bolted to the gimbal ring???I changed the gimbal ring and the tiller arm quite recently because of play in the steering.

Just go to FULL hyd. mats.......You have done the expensive part !
I did it...WELL worth the time & money Send a PM to Allan4...he
will tell ya !