Crowell Steering and Autopilot

[dwramia]

I have a 1966 41' Twin Cabin that was originally equipped with an autopilot on the Crowell steering system. The autopilot was not working and was removed. The pump for that autopilot is still in place and working. I purchased a Raymarine autopilot, installed and all seemed good until we tried to engage the steering.

A bypass valve (not the one used to balance the system just under the helm) was installed in the lines in the aft stateroom closet where the electrical panel and hydraulic lines come through and just about 2 feet above the pump and above the pressure canister.

The valve was closed to bypass the pump so engaging the autopilot caused the pump to try and move fluid but the rudders did not move. (assuming because lines to/from pump were closed off) When the valve is open the rudder arm moves as does the steering wheel at the helm but when you put the autopilot on "Standby" you can't manually turn the wheel. A bit of a safety hazard.

The Crowell instructions show a third (return line) port is needed on the box behind the wheel but the system only has two.

Anyone come across this or have suggestions. I can't imagine that the original autopilot required you to run down to the aft stateroom closet, turn a valve to have manual steering again.

Picture attached. The picture is turned upside down and not sure how to fix that :-(

Picture shows pump in aft stateroom closet. The valve is just above the pressure canister.


Dan

 

[Fanfare]

The Crowell steering units were standard on Hatteras until the end of 1965. My father was a naval engineer and when he ordered Fanfare he told Hatteras to install Hynautic steering. After using up their last sets of Crowells Hatteras switched to the newer Hynautic units. Years later Hynautic (originally Fluid Control Corp.) told me that Hatteras was their biggest customer.

The problem with the Crowell system is that all steering wheels are locked together. Turning one also turns the other. If you need aft steering that makes three. The friction involved adds up. Because there are no bypass valves your autopilot motor is blocking all fluid transfer. I suspect they were not intended for autopilot steering.

Now I am making this up: You could replace all your Crowells with more modern hydraulic steering. I suspect that if you just add a bypass that no steering would work. The fluid would just swish around instead of moving the ram.

If I am wrong, maybe you could run a long hose loop from the autopilot pump up to wherever you want to use the autopilot from, and open/close a valve right there. If your old autopilot ever worked this should do it.

Teleflex now owns Hynautic. I have no experience with their quality. I am on my third autopilot from the original Benmar. Each one has worked better than the one before. My advice is to replace the autopilot, the pump, and your Crowell units. You have gotten your money's worth by now.

 

[jim rosenthal]

Jim, did the Crowell units use the same kind of MilSpec hydraulic fluid that Hynautics use? If you know.

 

[rsmith]

I believe it was ATF just like the early Hynautic.

 

[Fanfare]

I don't know, but I would think hydraulic fluid is pretty much all the same. Milspec just states that it meets the government standard of quality.

I sure do like the red colored hydraulic fluid. The clear stuff looks just like water if you are looking for a leak.