'69 115hp shifting problems Hydro-Electric

jhereg

Cadet
Joined
May 28, 2008
Messages
6
Hey Guys,
i've been searching thru all the posts on shift related problems and cant find what i need.
i ran thru all the diagnostic routines and this is what i found:

original problem was shifting into forward while in the water killed the engine but not in the driveway.( this is still happening)

shift switch in control box checks out ok( it reads correct in all 3 positions)
solenoid are both reading between 5 and 6 ohms (disconnected)

the voltage at the solenoids is only reading 10.5v, i know it needs 12 to actuate properly. my question is: what would cause only 10.5v? the shift switch read:eek:pen=forward, .4 ohms=neutral, 1.3 ohms=reverse.
but 1.3 ohms couldnt cause that large of a drop in voltage and it read 10.5v in both neutral and reverse.
battery was fully charged and reading 12.6v.
this has been driving me crazy as i havent been able to hit the water yet.

Thank you in advance for any and all help.
 

emckelvy

Commander
Joined
Jan 16, 2004
Messages
2,506
Re: '69 115hp shifting problems Hydro-Electric

Frankly, I think you're barking up the wrong tree. The Hydroelectric lower unit's shift solenoids are energized only in Neutral and Reverse to shift the spoolpiece that ports oil from the hydraulic pump in the lower unit, to drive the shift clutch into Neutral and Reverse.

When there's no power applied to the shift wires, the lower unit is automatically spring-loaded into Fwd gear.

So, it's not an issue of the lower unit taking electrical power away from the engine.

It's an issue of the engine not being able to run in gear, with a load on it. The fact that it'll shift thru the gears out of the water really doesn't mean much since even a really lousy running motor will spin the prop when it's out of the water.

It could be something as simple as idle mixture adjustment or idle speed adjustment.

If I recall, your 115 has (4) idle mixture needles joined by a common linkage. You may need to disconnect the linkage and adjust each needle separately until you get a smooth idle in the water, in Neutral. Then, adjust the needles about 2-1/2 turn CCW and this should be a good initial idle-in-gear mixture adjustment.

If you can get it to idle in gear in the water, adjust each needle for best speed then go about 1/8 turn rich (CCW).

You'll probalby need to adjust the idle speed after doing this, to get the rpm at a place where the motor isn't racing, but won't stall when you put it in gear.

If that doesn't help, you may have issues with your carbs such as a plugged idle circuit. Try pulling the idle mixture screw out all the way and blowing air into the idle passage. Drain the carbs first or lay a rag over because this will tend to blow fuel out of the carb!

If that doesn't help, you may need to disassemble the carbs for further cleaning.

Of course if your engine has poor compression it's not going to run right, and no amount of tuning is gonna fix that. Compression readings should be at the most 10 psi from each other.

Anyway, try a few adjustments and see how that works for you. HTH......ed
 
Last edited:

tashasdaddy

Honorary Moderator Emeritus
Joined
Nov 11, 2005
Messages
51,019
Re: '69 115hp shifting problems Hydro-Electric

totally agree, idle problem you should be idleing at 600-750, in the water and in gear, it will idle higher in neutral and on muffs.

Carburetor Adjustment - Single S/S Adjustable Needle Valve)
(J. Reeves)

Initial setting is: Slow speed = seat gently, then open 1-1/2 turns.

Start engine and set the rpms to where it just stays running. In segments of 1/8 turns, start to turn the S/S needle valve in. Wait a few seconds for the engine to respond. As you turn the valve in, the rpms will increase. Lower the rpms again to where the engine will just stay running.

Eventually you'll hit the point where the engine wants to die out or it will spit back (sounds like a mild backfire). At that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting.

Note: As a final double check setting of the slow speed valve(s), if the engine has more than one carburetor, do not attempt to gradually adjust all of the valves/carburetors at the same time. Do one at a time until you hit the above response (die out or spit back), then go on to the next valve/carburetor. It may be necessary to back out "all" of the slow speed adjustable needle valves 1/8 turn before doing this final adjustment due to the fact that one of the valves might be initially set ever so slightly lean.

When you have finished the above adjustment, you will have no reason to move them again unless the carburetor fouls/gums up from sitting, in which case you would be required to remove, clean, and rebuild the carburetor anyway.
 

F_R

Supreme Mariner
Joined
Jul 7, 2006
Messages
28,226
Re: '69 115hp shifting problems Hydro-Electric

3rd agreement to clinch it. You are barking up the wrong tree. First thing first, set the idle speed up to where it will continue to run in gear. That may be all it needs. You can then fine tune the mixtures to see if it helps, but take it easy. Fine tune them from where they are, don't go compounding the problem by first seeing how far off you can get them. You already know they are mighty close to where they need to be.
 

jhereg

Cadet
Joined
May 28, 2008
Messages
6
Re: '69 115hp shifting problems Hydro-Electric

Thanks Guys, it sounds like I'm looking at the wrong area. i will follow the instructions and hopefully that is it. is the 10.5v instead of 12 at the solenoids a problem??
I unwittingly put regular gear lube in the LU, i didnt realize it needed lower viscosity until reading all the posts on the 115, could that be part of it too?
i am getting the correct lube today.

Thanks again for the help, i will follow it.
 
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