Mercruiser controls question/box adjustment/Shift throw measurement help.

[model14]

Please note the attached picture of the 1988 Mercruiser controls assembly. What is the purpose of the slot-headed screw just forward of the control handle? I assume some type of adjustment.
Thanks, Richard



Merged your two threads together to make it a bit easier.

 

[Bondo]

Re: Mercruiser controls question

Re: Mercruiser controls question

Ayuh,.... My guess is the screw is holdin' the neutral safety switch in place,....

 

[model14]

Mercruiser control box adjustment

Mercruiser control box adjustment

Is there a shift cable "throw" adjustment on a 1988 Mercruiser control box? The one in my restoration project is only giving me 2-1/2" cable movement and I need 3", per outdrive manual specs.
Thanks,
Richard

 

[Fun Times]

Re: Mercruiser control box adjustment

Re: Mercruiser control box adjustment

Hum can't think of any throw adjustments at the control box.

Have picture of the controller? (Edit: Found one) Looking at your picture in post #1 above, the design of the yellow base reminds me of this control unit model is used on Volvo Penta models. If so, I do recall the throw is different between Merc and volvo and long with the style of cable used.

Can you take more photos of both sides of the controller along with the cables at both ends (Engine and control unit.)?

Also look for a part number at the controller.

Have you see "checking remote control shift cable output starting on page 1C-42 & 43"? http://www.boatfix.com/merc/Servmanl/6/6C1R3.PDF

Also can you find your control unit starting on page 4A-1 +,
Boatinfo - Mercruiser Service Manual for Remote Controls

 

[model14]

Shift throw measurement help

Shift throw measurement help

If you have a Mercruiser Alpha Gen 1 and it shifts properly between forward and reverse, I would appreciate knowing how much movement you have in inches between forward and reverse on the outdrive shift cable. I am only getting 2 inches and it is not enough to allow engagement of both forward and reverse. It is one or the other, but not both.
Thanks,
Richard

 

[Fishermark]

Re: Shift throw measurement help

Re: Shift throw measurement help

The control cable should have a 3" travel - give or take 1/8". (The cable from the front - from the control).

Have you disconnected the shift cable (that leads to the outdrive) to see if it will shift easily by hand? Have someone turn the prop counter clockwise while you push in on the cable. It should go into gear. Do the opposite for reverse. I don't know the length of travel for the shift cable... but let us know if it shifts easily by hand.

 

[model14]

Re: Shift throw measurement help

Re: Shift throw measurement help

It shifts easily by hand, under power in the water, strapped to the trailer! This is a restoration project. It is almost like a bogus control box with only 2 inches of travel was installed, tried, didn't work, and the previous owner gave up and let the boat sit for two years. I paid low dollar for the boat and trailer, but the shift issue is kicking my butt! I hate to have to try a different control box. The nightmare image of wiring harness to fit is almost too much.
Richard

 

[alldodge]

Re: Mercruiser controls question/box adjustment

Re: Mercruiser controls question/box adjustment

Reading through both of your threads it seams your going to need to either replace your control box or get into it and find out what's wrong. The link in Fun Times post shows you the components

 

[model14]

Re: Mercruiser controls question/box adjustment/Shift throw measurement help.

I have read thru the service manual for remote controls and can find no reference to any adjustments of shift throw. The forward and reference detents are also not adjustable that I can see. Maybe someone will take a moment and take an actual measurement of shift cable movement. The 3" spec is just way off from the 2 I am getting.

 

[alldodge]

Re: Mercruiser controls question/box adjustment/Shift throw measurement help.

I would say move the handle to the forward position, grab the cable and if you can pull it out further by hand, the problem is in the control box and needs to be replaced or repaired. If you pull the cable and it doesn't move any further, you need to replace the control box.

 

[model14]

Re: Mercruiser controls question/box adjustment/Shift throw measurement help.

I believe I have found the problem, but I won't know for sure until I try shifting gears in the water with the prop under load. The fix works fine while running on the garden hose (did that before, though).

The problem appears to have been that the timing between the outdrive shift cable, the control box shift cable, and the control handle, was out of sync. Three things need to be in sync when in neutral, or in gear: the outdrive shift cable must be in the proper position, the interior mechanism, which stops the forward and reverse movement of the shift cable as the control handle continues forward to operate the throttle, must be in the proper position, and the control handle detent must be inthe proper position. If any one of the three are off during assembly then you will not have equal shift cable travel in both the forward and reverse positions of the control handle. Mine was off by 2 splines on the control handle, which is a bunch. My shift cable movement at the shift arm on the valve cover is now equal and almost 3 inches of travel. Hopefully, this correct the shift problem. I will let you know.

 

[model14]

Re: Mercruiser controls question/box adjustment/Shift throw measurement help.

Yeah!!!! Problem fixed per the above post. Took the boat on first trials today and all went well. Shifting went perfect.
Richard

 

[alldodge]

Re: Mercruiser controls question/box adjustment/Shift throw measurement help.

Sounds great, thanks for coming back and let us know