125 hp mercury 4 cyl 2 stroke slow to generate power and slow to start

sdseney

Recruit
Joined
May 19, 2013
Messages
3
i have 2001 125hp mercury 4 cyliner 2 stroke outboard. it is exhibiting the following problems:

difficult to start. when i turn the key, it turns over for 5-10 seconds before catching and running on its own. Sometimes it will need to be started 2-3 times before it runs.

Once started it runs fine in idel and low RPM <2500. But, above 2500 RPM it take a long time to generate power and get the boat up on plane.

Yesterday, it started and ran fine for 45 minutes. I then shut it down to do some fishing and it wouldn't restart. I got a tow back to the docks. Back at the marina, i connected a water hose to flush it out, and tried starting it to start troubleshooting and it started again with minimal issues.

Any troubleshooting helkp would be appreciated.
 

Laddies

Banned
Joined
Sep 10, 2004
Messages
12,218
Re: 125 hp mercury 4 cyl 2 stroke slow to generate power and slow to start

Clean your carbs the engine sounds lean
 

Urbina

Seaman Apprentice
Joined
May 10, 2012
Messages
47
Re: 125 hp mercury 4 cyl 2 stroke slow to generate power and slow to start

try using some sea foam if it helps then you might have dirty carbs and should take them off to clean them up.
remember do not submerge in carb cleaner since it will remove a protective coating.
just spray and let air dry
 

sdseney

Recruit
Joined
May 19, 2013
Messages
3
Re: 125 hp mercury 4 cyl 2 stroke slow to generate power and slow to start

is the sea foam something i add to the fuel tank, or do i need to remove the cowling to expose the carbs and spray on directly?
 

Urbina

Seaman Apprentice
Joined
May 10, 2012
Messages
47
Re: 125 hp mercury 4 cyl 2 stroke slow to generate power and slow to start

there are both products in the sea foam brand.
I would buy both dump in gas tank and spray in carbs directly.
If this helps and plugs back up clean out your carbs or rebuild them.
 

Laddies

Banned
Joined
Sep 10, 2004
Messages
12,218
Re: 125 hp mercury 4 cyl 2 stroke slow to generate power and slow to start

After the witch oil and your running around with a lean engine see if anyone volunteers to help with a burned piston
 

sdseney

Recruit
Joined
May 19, 2013
Messages
3
Re: 125 hp mercury 4 cyl 2 stroke slow to generate power and slow to start

After the witch oil and your running around with a lean engine see if anyone volunteers to help with a burned piston

why would the carb cleaner damage my cylinders?
 
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