Hynautic Engine Controls out of sync

[CPONTE25]

OA 486, new to me with dual Hynautic engine controls.

When moving the Pilot House throttles full travel and returning to idle, the RH throttle lever on the Flying Bridge remains at 1/2 travel (i.e. does not return to idle, while the motor does). When operating the controls in the flying bridge they operate normally and the P/H station's controls follow. Any ideas what could be happening?

 

[Lepke]

Probably needs to be bled. Any air in the system will cause other handles and maybe throttle and shifter not to move their full range. Look for leaks.

I'd get the manual out, or download one and go thru the bleeding procedure. Also a good time to fully learn the system.

 

[Martin J]

Needs bleeding , also they should be moved full ahead and back a few times , It centers them once bled properly. Once this has been established that all well bled etc. The final alignment can be done by slackening the bolt in the handle and centering them and retightening. prior to starting they should be moved back and fro 2-3 times To make sure they are synched with the rest of the controls.

 

[vacser]

I had the same thing happen on my Mainship. Would throttle up fine. When I pulled back STB engine would stay up. They make a $38 kit to rebuild. Very easy to do. Mainship had quick connectors under the controls for easy removal and no fluid loss. After replacing o-rings. everything worked fine https://www.seatechmarineproducts.c...trol-shifter-and-throttle-slave-seal-kit.html

 

[DCDC]

Also had this issue, once on a throttle and one on a shift. Twin JD 6068’s with elderly Hynautic controls. There is a valve manifold between the pressurized reservoir and the hydraulic actuators. These valves are normally closed, isolating the control loops from the reservoir. Over time a small leak (mine looses a 1/4” a year, not much) will depressurization a loop. I just open the manifold valves for a second to re-pressurize. I was told that the newer versions do this automatically. I do this every six months or so. A lot easier than bleeding loops.

If your seals are leaking you should be able to see fluid oozing out somewhere.

I also keep the reservoir at 60-80 psig, re-pressuring approximately yearly. One of the things I check daily when cruising. I was also told to exercise the controls several times, pausing at each end, before starting the engines especially if they had not been used for a while.

The company who purchased Hynautics (Seastar) did not seem to have much experience with older units but referred me to a retiree who was quite helpful.

Picture of valve manifold attached. Good luck.

 

[CPONTE25]

I had the same thing happen on my Mainship. Would throttle up fine. When I pulled back STB engine would stay up. They make a $38 kit to rebuild. Very easy to do. Mainship had quick connectors under the controls for easy removal and no fluid loss. After replacing o-rings. everything worked fine https://www.seatechmarineproducts.c...trol-shifter-and-throttle-slave-seal-kit.html

In my case the 2d station lever stays at 1/2 while the engine does return to idle.

I'll try to re-synchronize and see if that helps. Will check for air and bleed... Thanks folks...