Throttle and shift cable for mercruiser

[Fireman115]

So last year I put a new to me motor (mercruiser 3.0 LX) in my boat as the block was cracked. I replaced all bellows boots cables gimbal everything. Now when I shift from reverse to neutral or forward the boat stalls, unless I shift really fast and I know that not good for it. What I'm wondering is the throttle cable and the shift cable the same? And are they the same length? I was thinking they were the same and same length because they basically go to the same spot to the motor. Also will this solve my stalling issue? If not what am I doing wrong or what do I need to do to fix this? Any and all help is appreciated. Thanks in advance.

 

[Chris1956]

MerCruisers have an upper and lower shift cable. The lower shift cable goes to the outdrive and connects to an ignition killer switch, on the block, near the upper shift cable. If the lower shift cable binds, the switch is activated, and the ignition is killed. You might check for this.

Lower shift cables do wear out and need replacement. The procedure is not straightforward. I would suggest a service manual.

 

[Fireman115]

MerCruisers have an upper and lower shift cable. The lower shift cable goes to the outdrive and connects to an ignition killer switch, on the block, near the upper shift cable. If the lower shift cable binds, the switch is activated, and the ignition is killed. You might check for this.

Lower shift cables do wear out and need replacement. The procedure is not straightforward. I would suggest a service manual.

I replaced that lower shift cable and all the bellow boots that's why I'm thinking it has to be in the upper part.

 

[dubs283]

see here:

HOW TO: How the Shift Interrupt system works

Usually in the spring and summer we get a lot of posts regarding the shift system for the MC-1 (falsely referred to as Pre-alpha drives) to the Alpha 1 drives. There are a lot of wrong ideas on how and why the system works and why it's there to begin with. Maybe this will help explain how it...

forums.iboats.com

 

[achris]

A completely frozen remote shift cable (what you're calling the upper) cannot activate the shift interrupt switch. If you're killing the engine on shifting, it's most definitely NOT your upper shift cable. Most likely you kinked the new lower shift cable on installation, or it's routed incorrectly, or the adjustment is out... Other possiblities are, bent shift shafts, binding upper shift shaft bushing. Bottom line, you're problem is south of the upper control cable.

Chris...
And I'm going to move this into the MerCruiser forum...

 

[Fireman115]

So I just looked and it's run right, no major bends in it. I don't get it. What if I just disconnect the safety, I know it's there for a reason but I'm stumped

 

[achris]

So I just looked and it's run right, no major bends in it. I don't get it. What if I just disconnect the safety, I know it's there for a reason but I'm stumped

It's not a 'safety', it's a shift interrupt... Nothing to do with safety.

Did you read the link Duds posted? (How the interrupt system works)

 

[Fireman115]

It's not a 'safety', it's a shift interrupt... Nothing to do with safety.

Did you read the link Duds posted? (How the interrupt system works)

Yes I know how it works. But it only cuts the engine going from forward to neutral. Reverse to neutral it doesn't. I could see if there were some major bends in the cable but there are none. Now if I go really fast from forward to reverse it still trips but it's quick enough that the engine doesn't die. I can take pictures Saturday as I will be out of town all day tomorrow and it's already getting dark here. Just let me know what is needed for pictures.

 

[achris]

So, you're left with bent shafts, or crud in the slide or slide cavities.