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1984 Mercury 70 hp stalling

I have a 70 hp Mercury with 4 cylinders that is stalling when u put it in gear. Runs fine when you can get it engaged. Have the serial # but it's partially obscured. Idle is high after high speed runs. Any thoughts?
 
Could be the carbs and fuel pu

Could be the carbs and fuel pump need rebuilt. But check the basics first. Fuel lines and especially primer bulb should be soft and pliable with no cracks. Vent clear on tank. No loose connections.
 
Ok I'll check these asap.

Ok I'll check these asap. Will run some seafoam through and will also check compression. Can I just drop float bowls for inspection of dirt or grime. I just bought this boat and motor and seller claimed to have had carbs rebuilt last year. It starts fine just won't run when put in gear. Thanks for your help.
 
"I checked the primer bulb, so

"I checked the primer bulb, soft and flexible, and all lines. Removed pickup from tank and it's clean and vent open. Runs fine at any throttle while on plane but just doesn't want to go into gear without stalling. Thanks."
 
"might possibly need the idle

"might possibly need the idle turned up just slightly, or is could be in the ignition cut off is out of adjustment"
 
It idles normally when just st

It idles normally when just started but idles high after a run. Where is the ignition cutoff and how do you adjust it. I'm checking compression now. Thanks.
 
the ignition cutoff is up by t

the ignition cutoff is up by the fly wheel. on the 150 hp motor it has a cable that activates it attatched to the shift linkage you will need a manual to correctly adjust this to spec.
 
"Ok I'll get the manual to

"Ok I'll get the manual to check ig. cutoff. Took compression readings: #1 130+, #2 130+, #3 120, couldn't get to #4. Filter looks clean and no signs of gas leak around the float bowls. Thanks"
 
Does the fuel pump have a filt

Does the fuel pump have a filter or screen? Wouldn't any trash not let the motor run so well at 1/4 and above throttle? I appreciate all your help.
 
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