Mercontrol shift/throttle question

[998cc]

Boat: 1972 Gulstream, 18' fish/ski boat. Mercruiser MC-1 with L-6 250 (GM) motor.

First off, I have never driven this boat. It is a new-to-me boat that has been a restoration project since March 2013

The control unit is pictured in the Mercury Service Manual C-90-71707 on page 7C-4 and 7C-5. Numbers mentioned at the top of the page are: C-37782A1-A2 and B-64326A1-A3. It is mounted in the sidewall next to the drivers knee. The cables are all free at this point, and the engine and stern drive are not installed.

Curiously, the control seems to be reversed. It will "shift" when pushed forward, but that's it, no further forward travel unless the button is pushed in. When pulled aft, the control shifts and will operate the throttle to WOT when pulled further aft. I doubt this is normal, but please correct me if it is. If not, is there is something amiss or reversed in the control??

Thanks.
Russ 998cc

 

[998cc]

Re: Mercontrol shift/throttle question

Given there have been no replies, perhaps this was not considered by the group to be a serious question. It actually was.

 

[Bondo]

Re: Mercontrol shift/throttle question

Given there have been no replies, perhaps this was not considered by the group to be a serious question. It actually was.

Ayuh,... Or We donno,.... Take it apart, 'n see what's broken,...

 

[SunbirdChaser]

Re: Mercontrol shift/throttle question

View attachment 212792Boat: 1972 Gulstream, 18' fish/ski boat. Mercruiser MC-1 with L-6 250 (GM) motor.

Curiously, the control seems to be reversed. It will "shift" when pushed forward, but that's it, no further forward travel unless the button is pushed in. When pulled aft, the control shifts and will operate the throttle to WOT when pulled further aft.

I'm also new to Mercruiser, and my boat is an early alpha and the control is different. I think they are similar in how they operate. That said, with the throttle pulled out for neutral, the button is bypassed, and only the throttle is moved by the lever. With the lever in the seated, drive position, pushing the button allows the shift cable to place the lower unit in fwd or rev, before the throttle advances the rpm. If the lever moves more then a few millimeters without the button being pushed, I'd say something inside is broken. with the engine removed, you should be able to watch the ends of the cables move.
Hopes this helps.

 

[84EdH]

Re: Mercontrol shift/throttle question

I am confused. when you say it will "shift" but no more forward travel. do you mean the handle stops once shift is felt, or do you mean the throttle cable wont move forward ? also, when you say the cables are free...no engine, no outdrive. do you mean the cables are disconnected from the shift plate in the back of the boat? or do you mean they are connected to the shift plate, which is hanging in the back of the boat? (with lower shift cable still connected? I will try and help once I understand your problem a bit better.

it seems either the remote control mechanism is faulty, or one of the cables is binding, or corroded.

 

[998cc]

Re: Mercontrol shift/throttle question

Ayuh,... Or We donno,.... Take it apart, 'n see what's broken,...

Thanks to all who responded. I am 90% sure it is not a cable issue, so I will take Bondo's suggested course and open 'er up.

 

[998cc]

Re: Mercontrol shift/throttle question

OK. I am working on the boat this weekend and hope to have it in the water either Monday or next Saturday. The control box is apart, but all looks just fine inside. I did notice the wiring to the micro-switch had rubber insulation that rotted, so new wires are going on later today.

I think I can resolve my original question with the answer to this one. There are two cables coming off the control, 1. Shift and 2. Throttle. When shifting from neutral into Forward, is the Shift Cable inner extending away from the control box, or is it being retracted back toward the control box??

998cc Wantin' to go fishin!

 

[998cc]

Re: Mercontrol shift/throttle question

Found the problem! The problem was not with the control box at all. what was happening was the shift cable "outer" was adjusted in a manner that would not allow the control box innards to move past the point where the throttle would begin to advance. A quick adjustment back at the shift plate, and all is good.