Crowdthinking my Hynautics Engine Controls

[Amberjack]

As some of you know I've had a challenge with my starboard engine throttle control. It believe is original equipment to the boat, the 04 series, and the lower throttle works as it is supposed to but the upper throttle will only advance if I jam it forward quickly from idle, then will only retard if I ease it forward to full open, then pull it back. There must be bypass leakage somewhere. Because the lower station sender works I assumed the issue was the upper station throttle sender but I've had it apart twice, replaced the O rings and tested the Dill valves. I've done the same with the slave master unit. So, today I'll take apart that throttle charging valve to see what that does.

There may be a lot of these systems still out there on B31's and I suspect some have already encountered this same issue and solved it. If you have I'd like to hear it and probably should have asked advice a couple months ago to save myself time and aggravation.

[Bruce]

It sounds like the upper control has not been bled properly.
Do you have the hynautic book and bleed sequence?

[Amberjack]

Yes, thoroughly and repeatedly bled. The feel isn't spongy with a bounce back at the end of travel as it is with air in the system, its more like no throttle effect because the cylinder pressure is bleeding away instead of moving the slave.

I took apart the charging valve today and everything looks normal. Then pulled the pilot check valve today and will take it apart tomorrow. Really my last option.