How to pump up Hynautic transmission shifter to 70 psi air pressure ?

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Dune

Senior Member
Joined
Jul 14, 2015
Messages
389
Location
USA
Vessel Make
Viking 65 CP MY (run at trawler speeds !)
Bought a cheap bicycle pump rated at 70 psi to pump up the Hynautic for the steering but that one only required 25 psi....But I could tell from the effort just to get to 30 psi that doing 70 with that particular pump would be unlikely to happen. I didn't try as I was afraid of letting out more air in the process (currently at 55 psi....but supposed to be at 70)

Of course I could use a little nail gun compressor...got two of those already for my business... but rather avoid that hassle if possible as they are kinda heavy for extended lifting.
 
Other bike pumps will go to 150+ psi. Possibly the one you got is for mountain bikes. More air volume per stroke less pressure overall.
A road bike pump would have less air volume per stroke but a higher overall pressure capability. It will usually have a smaller diameter tube and be easier to push at the higher pressures.
 
I keep the Hynautic at 12 psi as per instructed by electronic tech. He informed me that higher pressure significantly increases wear and stress on the autopilot pump. At 12 psi the system works well.
 
I have a 150 psi 12 volt tyre pump I connect and maintain my system @80 psi.

Every 18 months I change the glycol mix and flush, it seems to produce a dirty contaminated fluid on the transmission systems.

As fyi to strip and replace the seals you need pin wrenchs. It took me ages to find them that fitted. https://www.amazon.com/CRL-USW10-Un...?ie=UTF8&qid=1477760222&sr=8-2&keywords=usw10 I had "creep' on my throttles for ages but could not find the correct pin wrench. This tool solved the problem
 
Hmm...I don't recall Hynautic steering requiring high pressure for the steering unit.

Other than perhaps for bleeding.
 
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The OP was asking about hynautic transmission shifting not steering.
 
The OP was asking about hynautic transmission shifting not steering.
Right, I might have further confused matters by mentioning pumping the steering unit to 30 psi but that was just an experiment to see how much effort the pump took to get it there. Afterwards I bled it back to the called for 25 psi spec.

And to whoever mentioned 12 psi, that is about what mine was at previously and worked ok at that on lower helm, but I was having some steering issues on the flybridge helm until I got it to 25 psi. Hydraulic reseviour levels were good...a little too much if anything. (measured with wood dipstick, not trusting the sight glasses)

As an aside, this pump is a full size stand on pump but only cost $5.50 new at the hardware store ! No doubt, made in China, but it looks exactly like a typical bicycle pump that would have been under my Christmas tree in 1960, including the name, logo and packaging.....time warp city... LOL..
 
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Thought we were refering to the engine controls? in particular the transmission shift? Not the steering?
 
I use a Harley Davidson pump from my M/C that is used on the shocks and on the Police Saddle air bladder. It loses nothing when detaching. It has it's own accurate gauge. It is small and compact. The perfect little pump. You don't need volume.
 
Did you open the system up? Change a line? As long as the air pump is capable of pumping to that capacity (have you tried to pump a HP bike tire with it?) If the pump is capable, but the system won't press up it has air in it. Air is compressible. Fluid is not. Make sure all the air is bled out.
 
To synchronize you can use your ears and butt. :D
I use ears, hands and feet....even though I have Glendinning rpm syncro, I tend to not use it.

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As an aside, I also have Glendinning CableMaster on port side for two 50 amp cables. The stupid part is I had the boat docked for over a year on the starboard side to T head float and ran the cables all the way around from port across the forward deck thru bulwark hawse pipe to dock power.

Worked fine but in that time the cables went from looking like new to looking terrible (bright shiny yellow to flat slightly faded yellow, plus black marks everywhere)... and tended to catch dirt underneath on the boat deck as well.

Only recently discovered I had brand new set of regular 50 amp cables (plus Y connector in case of marina where only one 50 amp available*) in the storage inventory that I should have used instead via the standard fittings on port side of boat.

Of course if we had used those separate cables they would have looked bad eventually as well but at least those could be replaced at way less cost than the much longer Glendinning cables, and the forward deck would have stayed cleaner.
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*In the hottest of the summer, with most hvac running and if cooking or other high amp use, we actually need nearly 100 amps however..... so the Y connector would only be a "better than nothing" compromise if traveling in summer in the south.
 
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