Hynautic Steering 1974 Magnum Maltese
 

Hey guys,

Got a unique problem with my hynautic steering. H-21 helm, reservoir, relief valve, and cylinder. I have no leaks, and air pressure is holding very well dropping only about 10lbs every month. Steers very well with no issues (yet!). However if I straighten out the drives (twins) on the trailer they will not stay straight overnight or over the course of a week. The drives will always turn to Starboard. The cylinder rod is actually being pushed out on the cylinder, not retracting.

Anyone ever have a similar problem or have any thoughts?

Thank you,

Jeff

Jeff, is it a single cylinder? Does the piston rod extend through or is single ended? Can you post a photo of the cylinder?

Marc,

It is a single cylinder. Been fine for over 40 years! No leaks currently, just moves drives to starboard now overnight by itself when left straight at end the day. It is actually moving the cylinder rod out (extending) and turning the drives. Up side is that drives are really in good shape and turn that easy! LOL! Tells me that fluid is escaping from that side of the cylinder back to the reservoir some how? It an unbalanced cylinder old school hynautics. I will post a picture later.

Any thoughts?

Thanks for the reply.

Jeff

Sounds like an internal leak in the system, causing the extend pressure to be greater than the retract. Is the wheel moving as well? Neighbors playing a trick on you?

I think murfman has it right. I am guessing it is the check valve connected to the side of the cylinder where the piston rod is. There is less area on that side of the cylinder (the diameter of the piston rod) so there is more physical pressure on the extend side.

Thank you guys, I am thinking same thing. Was just hoping someone may experienced this in the past and I could isolate the leak to either the helm itself, the relief block or the cylinder without having to replace all three during the process of elimination! LOL!

Great question about the steering wheel, haven't paid attention to it up until now, just pissed about the drives turning on there own. I will set it and check this weekend.

See attached photos.

Thanks guys, keep the thoughts coming!

Jeff

Side question, how do you like the steering set up that way? I have a Hynautic dual ram setup that I was going to mount externally, but I'd like the clean transom with all the hardware inside as well. My Volvo transoms are rebuilt and tight as a drum, but I do realize the helmet, arm and pivots are all sources of slop and play.

If you are ever going to run the boat hard external is a must.

Murfman, I love it. Clean transom, easy to work on, and ran hard for 42 years! Same setup! Raced for two years in 74 and 75 and countless Poker runs after that. 270T and single ram hynautic cylinder steering still going strong.

Thanks again for the help, I'll keep you posted on the cure. It may help someone else.

Gorgeous looking Maltese,