Merc 40 Force - Takes forever to start

joeyd0315

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May 8, 2023
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Hi All, i'm not real knowledgeable about engines, but have been searching all over online for some things to try, to no avail. I am guessing i should be able to adjust the engine or carburetor to make this work better. Once it starts the engine runs fine, so that is good. But getting it started is challenging. Normal key push choke does not do anything, engine cranks and cranks but never starts. I proceed to use the disable button on the throttle and push forward. I need to push it all the way up, and after many attempts the engines starts but very loud b/c it is at full throttle. if i pull it back to neutral too fast, it will stall out. If i do it too slow it is so loud. Fuel ball pump is full so that is not it. Eventually after many attempts, it will not stall in neutral and can get on my way. What can i adjust to make sure there is the proper gas/air combination to start the engine normally with the key start/choke? 2 stroke, 1996 Mercury 40hp Force
thx
Joe
 
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joeyd0315

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May 8, 2023
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Is it hard to start after it's warmed up?
It takes so much effort to start, i don't turn it off to see if it will start again, i could try that. But yesterday, went out to the middle of the lake for about an hour, then it took 10-15 min of messing with it to get it started again. Ugh
 

flashback

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I was thinking the choke is failing but if it's hard to start when warm that's probably not it unless you're choking when it is warm..
I'm shade tree but more capable folks can help you with this..
 

racerone

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Are you pushing the key in AND holding it in while cranking it over ?
 

jheydubya

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I had this same issue with a 50 hp force motor. I rebuilt the fuel pump, replaced all fuel lines, replaced ignition switch cleaned connections.

Replacing the starter fixed the issue. It starts immediately now, especially warmed up.

edited to add, my starter wouldn't crank it would sit not making any noise then finally all of a sudden engage, but curious if your starter could not be strong enough?
 
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jerryjerry05

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Sounds like the primer is bad??
Cover off, key on, have someone push in the key as you touch the primer, you should feel a click. No click???
Test light, same procedure but use the test light on the wire.
This should light the light. No light? Then the key switch might be faulty.

Key switch: WD 40 spray into the switch and activate the choke function.
 

racerone

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You have likely damaged the starter with lots of cranking.-----Some will argue .----I would take starter apart for inspection.-----Do not rush out and buy a new one !
 

jerryjerry05

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Like Racerone suggested, check/rebuild or just clean it out.
Makes a huge difference in the way it works and adds years to it's life.
The brushes sluff off and they leave carbon bits in the bottom and that can short out the works.
 

jlh3rd

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Jul 10, 2017
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Hi All, i'm not real knowledgeable about engines, but have been searching all over online for some things to try, to no avail. I am guessing i should be able to adjust the engine or carburetor to make this work better. Once it starts the engine runs fine, so that is good. But getting it started is challenging. Normal key push choke does not do anything, engine cranks and cranks but never starts. I proceed to use the disable button on the throttle and push forward. I need to push it all the way up, and after many attempts the engines starts but very loud b/c it is at full throttle. if i pull it back to neutral too fast, it will stall out. If i do it too slow it is so loud. Fuel ball pump is full so that is not it. Eventually after many attempts, it will not stall in neutral and can get on my way. What can i adjust to make sure there is the proper gas/air combination to start the engine normally with the key start/choke? 2 stroke, 1996 Mercury 40hp Force
thx
Joe

these engines use a choke solenoid.....like these.....
should be an audible click when pushing the key in...
 

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racerone

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The 1996 model FORCE is shown to have an ENRICHMENT valve and not a choke flapper that blocks ( chokes ) air.----A wise owner would test all components that pertain to starting a motor !
 

flashback

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The 1996 model FORCE is shown to have an ENRICHMENT valve and not a choke flapper that blocks ( chokes ) air.----A wise owner would test all components that pertain to starting a motor !
I have a yammy motorcycle that has the enrichment rather than choke.. does the same thing but totally opposite approach...
 

racerone

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Nobody can see or hear this motor.----In my opinion it should not be hard to figure out a " hard to start " condition.
 

jheydubya

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"Hi All, i'm not real knowledgeable about engines," literally the first words in his post.
 

1985 Century Mustang

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Hi All, i'm not real knowledgeable about engines, but have been searching all over online for some things to try, to no avail. I am guessing i should be able to adjust the engine or carburetor to make this work better. Once it starts the engine runs fine, so that is good. But getting it started is challenging. Normal key push choke does not do anything, engine cranks and cranks but never starts. I proceed to use the disable button on the throttle and push forward. I need to push it all the way up, and after many attempts the engines starts but very loud b/c it is at full throttle. if i pull it back to neutral too fast, it will stall out. If i do it too slow it is so loud. Fuel ball pump is full so that is not it. Eventually after many attempts, it will not stall in neutral and can get on my way. What can i adjust to make sure there is the proper gas/air combination to start the engine normally with the key start/choke? 2 stroke, 1996 Mercury 40hp Force
thx
Joe

I'd spray some carb cleaner or starting fluid into the carb when it doesn't start right away and see what happens. If it starts right up, its definitely a fuel issue, a bad fuel pump, a clogged fuel filter, or just a bad carb altogether. Rebuilding carbs aren't that bad, if you have a good youtube video to go by. My 0.2 cents....
 

joeyd0315

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May 8, 2023
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10
I had this same issue with a 50 hp force motor. I rebuilt the fuel pump, replaced all fuel lines, replaced ignition switch cleaned connections.

Replacing the starter fixed the issue. It starts immediately now, especially warmed up.

edited to add, my starter wouldn't crank it would sit not making any noise then finally all of a sudden engage, but curious if your starter could not be strong enough?
thanks for the input. my starter seems fine, cranks away.
 

racerone

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" once the engine starts it runs fine "-----And what if the cranking ( flywheel speed ) was borderline ?----Some will argue.----In my opinion it cost nothing to inspect the starter.----There may be nothing wrong with it.----For zero $$ you can be sure of it.----Have battery load tested as well !!
 

jlh3rd

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Messages
560
The 1996 model FORCE is shown to have an ENRICHMENT valve and not a choke flapper that blocks ( chokes ) air.----A wise owner would test all components that pertain to starting a motor !
No...
It uses a solenoid to operate the enrichment valve that serves the same purpose as a choke....some call it a choke solenoid....
just like I said....
thats what he needs to check...not the enrichment valve....
and it makes a noticeable click......which is what he needs to hear.....when he pushes in on the key...
 

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