78Johnson 70 wont idle, hard to start

[78terryabf]

my first boat, WOT is excellent just floods carbs trying to start and refuses to idle at low rpms making it hard to get it moving forward before it stalls. If it gets moving it runs all day fine until i slow down to idle then it stalls and is hard to start again. any help is apprec..

 

[jonesg]

Re: 78Johnson 70 wont idle, hard to start

Hi there,

how do you know its flooding at startup?

What is your exact starting proceedure ( cold engine).

Bottom line, it really sounds like the low speed jets are clogged.
It might be dry at idle, not flooded.

New to you, order a carb rebuild kit for ea carb, its a very simple job but make certain to run wire thru the jets to be certain theres no junk in them.
Watch a vid of a johnson carb rebuild.
http://www.youtube.com/watch?v=o5cxBMDezuU&feature=channel_page

 

[jtexas]

Re: 78Johnson 70 wont idle, hard to start

Hard to start cold, warm or both?

You just acquired this motor, and been like this since you got it?

Engine not running, air silencer cover off, motor tilted full up, pump up the primer bulb -- if gas comes out the carb throats, your float valves are shot and need replacing, they're flooding the motor at low RPMs.

Either way, dry or flooded, carb rebuild is the answer. These carbs are remarkably simple devices, don't be intimidated.

You should be running Champion QL77JC4 plugs gapped at .030.
If you don't know how old the water pump impeller is, or if it's more than 2 years, plan on replacing it at your next available opportunity.

I'm guessing from your screen name that motor is installed on a 1978 Terry tri-hull bass boat -- am I close?

 

[78terryabf]

Re: 78Johnson 70 wont idle, hard to start

Thanks for the responses. I will pull carbs and run wire through the small injectors. I will replace the water pump asap. I will repost results.