Large dead spot in throttle

[ssaumure]

Hey folks, just purchased a 1982 Johnson 90HP, The motor starts and idles perfect but I have a large dead spot in the throttle. I removed the engine cover and watched the motor throttle lever as I increased throttle. The motor lever doesn't move until you get to about 80% full throttle. Was wondering if this would most likely be an issue in the remote control or just a cable adjustment?

 

[Willyclay]

Welcome to the iboats.com forum! The members here are great and the experts, which I am not, can help you with any issues on your motor. FYI, most two-cycle outboard motors accelerate to 2/3 - 3/4 throttle with only spark advance before the carb opens fully. As you suggest, it may be either a remote control issue or the cable needs adjusting. Hopefully, one of the forum gurus will post in with some specific recommendations for you. Good luck!

 

[ssaumure]

Thanks Willy. The boat that came with the motor is going to be a huge project, can't wait to show before and after pictures.

 

[emdsapmgr]

You can disconnect the throttle cable at the engine end. If you move the throttle by hand, the roller should immediately contact/move the throttle cam and the spark advance. That's normal. If it does not move (just like when the cable is attached) you will want to verify your sync-and- link settings. That re-adjusts the relationship between the spark advance and the throttle advance. Per the factory service manual. to clairify: When you move the throttle lever, you will see the shift cable will activate immediately, shifting into forward. Once the engine is fully in forward, then the throttle will start to move.

 

[ssaumure]

Ok, disconnected the throttle cable at the motor and moved the throttle by hand. The spark advance moved along with it. Moving the lever on the remote control caused the shift cable to advance. I'll add some pics to show what's happening. Sorry it's messy. Lots of grinding going on.

So this is neutral, everything is as it should be.

This is at the initial "click". Shift cable advances and everything still seems normal.

This is where I have to advance to in order for the throttle cable to move the throttle lever on the motor.

This is full throttle (on the control, not on the motor).

 

[Av3ngeme]

It sounds like the cable may have pulled apart inside the control box. They're pretty easy to take apart, just remove the few screws and take a look at the throttle cable and see if the cable has pulled away from the end at all...if not maybe the throttle cable just needs to be adjusted.

 

[ssaumure]

Thanks, I'll give that a try.

 

[Willyclay]

It's usually the simple stuff!

 

[ssaumure]

Checked the cable and it hasn't cime apart but I believe it is binding inside the sleeve. If i try to push it from the control end it only slides a little ways before I can't push it anymore. If I pull from the motor end then it will slide. Judging by the look of the sleeves they are fairly old. May be best just to replace them. What's the usual life span of throttle cables?

 

[redneck joe]

for $50 I'd just replace both. I've only done it once a long time ago on a cable of undetermined age.