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90 HP Merc Outboard hard start

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Finn92

New member
Hey guys so I have a 90's 90 HP Merc outboard with a key/choke ignition(Im new to boats but pretty mechanically proficient). Ive been having problems starting the boat. The engine will crank and crank and crank and start to fire but will often die. Eventually I can crank long enough that it fires and starts chattering away. When it does it sounds great no issues and no hard idle. I brought it down to the docks at the end of the summer and put it in the water but could not get it started.. i think the back pressure was a little too much for her to fire.

To start it I:

Put the water muffs on
Pump the bulb till hard
Advance the throttle slightly
Turn and crank
It will crank and crank and crank and eventually start

When I push the key in I can hear the choke click.

I pulled the cover off and found myself looking at the enrichener valve that feeds the carbs. I think it might be faulty but need an opinion. I pushed the manual prime on the bottom and could smell fuel. It did start a bit easier when I did this aswell.


Do you guys think I need a new valve? Or should I investigate the solenoid and choke aswell?

The boat has spark(new plugs) so it must be a fuel issue.

Thanks guys

Grant
 
Advance the throttle more and hold the key in WHILE CRANKING it over.-----------------Your starter may also need attention since it sounds like you have been getting it too hot !
 
racerone said:
Advance the throttle more and hold the key in WHILE CRANKING it over.-----------------Your starter may also need attention since it sounds like you have been getting it too hot !
Click to expand...

I have tried holding it in and cranking and it doesnt do much. The starter probably does need some love as it has been stressed with me trying to starting it. The motor had sat over the winter before being started in the summer. I put fresh mixed fuel in and ran some seafoam through it to see if that would fix it. How can I tell I tell if the starter is faulty. It still turns enough to crank the engine over
 
The starter is easy to take apart for inspection / new brushes and an ohm check from commutator to the shaft.---------It can be difficult for folks to grasp the concept of --------SLOW CRANKING = EQUALS NO SPARK
 
racerone said:
The starter is easy to take apart for inspection / new brushes and an ohm check from commutator to the shaft.---------It can be difficult for folks to grasp the concept of --------SLOW CRANKING = EQUALS NO SPARK
Click to expand...



Okay I'll put it apart and give it a look
 
Are you sure the enrichener valve is working properly? If not, there's no 'choke' action to get her going.

Jeff
 
Okay so I pulled the starter... hooked it up to my car battery and the gear will go to the top but slowly drop down. think my starter may not be spinning fast enough. Should the top port of my enrichener valve squirt fuel ? I pull the line and cranked it and nothing came out. had fuel on the carb side though.


Grant
 
That primer is NOT pressurized.---It is NOT a pump---Fuel does not squirt out when key is pressed.----When engine is turning fuel is drawn from this open valve when key is pushed in.
 
Thanks racerone. So I pull the starter apart. Cleaned all the carbon off and hooked it up to my battery she's spinning fine. When I turn the key I don't hear my starter solenoid clicking.. it should click right? Only click I hear is my enricher valve when I push to choke. I'll get an ohmmeter on the switch tonight to see what's happening
 
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