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'73 Johnson 85hp Trouble cold starting

M

McCormick87

New member
Just picked up a 15 foot Forrester with an 85hp Johnson. Model number is 85ESL 73m

The problem I am having is the motor not starting when cold, turns over fast, primer bulb pumps until hard as it should be, choke fully closed, but it will not even try to start. One little squirt of mix-gas into the intake, and it takes right off and runs good. Once it has been started like this, you can shut it down, and it will start right back up again on it's own. But if it sits for even a half hour, I have to squirt gas into the carbs to get it to pop off again.

What I have done:
Disassembled and cleaned carbs
Tested compression (115, 115, 115, 125)
New battery
New spark plugs

I've checked spark with an inline parts store spark tester, and if anything spark seems a little weak, the spark is orange, not blue like I have been reading you should have? But is consistent between all four cylinders.

I'm thinking fuel pump, not sure how to test? or weak spark issue. I'm just confused as to why it starts perfectly when warm, but not after sitting at the fishing spot for half an hour, and I would love to have a boat that I can spend the day on the water without taking the motor cover off...

Any help is appreciated, thanks in advance, Adam
 
The fuel pump has nothing to do with the hard starting !---------Have an assistant actually hold the choke flappers closed.------Is the timer base rotating slightly when use the fast idle lever ?
 
I'm not terribly familiar with these, so excuse my ignorance, but is the timer base what rotates under the flywheel, pushed on by the throttle linkage? If so, with the fast idle lever all the way up, the timer base rotates until it hits a stop screw.

My electric choke is not hooked up, so I am choking it manually, and with the carb cover off the choke is fully seated.

I should add some more back story, the last thing the previous owner did to the boat was to install new throttle and shift cables. (side note: I thought ES in the model number meant hydro-electric shift, but this one is most certainly manual cable shift)
The first thing I did, after cleaning carbs to make it run, was to adjust the cables. Not sure if there is a 'right way', but I have them adjusted so it fully shifts before throttling up, and it does achieve WOT. Anything I'm missing? Carb butterflies are synched and both close fully.
 
You mentioned orange spark not lightning blue snap.Spark test needs to be done.Tester can be hand made with wood and finishing nails
 
Why not have an assistant actually hold the choke plates closed when starting the motor.----------And does the timer base rotate slightly when using the fast idle lever for start up.
 
McCormick87 said:
...but is the timer base what rotates under the flywheel, pushed on by the throttle linkage? If so, with the fast idle lever all the way up, the timer base rotates until it hits a stop screw...
Click to expand...

I have pulled the choke lever out manually, and wedged a screwdriver in the linkage to make sure the blades are as tightly closed as possible, and have the intake cover off to visually verify the choke is closed completely.
 
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