Mercury 225 offshore almost dies, then starts up again

jerogers

Cadet
Joined
Jun 22, 2010
Messages
7
I have 1995 Mercury 225 Offshore it has been with an authorized Merc mechanic for three months (new mechanic,old one retired), He can not find out why it starts, slows to almost stopping, then starts up again, repeating till he shuts it down. The motor beeps when it starts, it stalls to the point it beeps again and starts running. He has tried a new wiring harness in the power head, checked the rest of the electrical, called Mercury, but it is still not fixed. Put in a new alternator last week, still not right. Fishing season is here, we finally get a season on the Nor PacificOceans and still not boat. Any help will be appreciated. I have checked all of your other threads and faqs.
Thanks again
 

sschefer

Rear Admiral
Joined
Nov 13, 2008
Messages
4,530
Re: Mercury 225 offshore almost dies, then starts up again

Who is working on your motor? I'm in Nor Cal also... Sounds like the idle stabilizer to me if it's still on the motor (or ever was).
 

jerogers

Cadet
Joined
Jun 22, 2010
Messages
7
Re: Mercury 225 offshore almost dies, then starts up again

A shop in Paradise. The motor does not have an idle stablizer. Now he has put in new coils which hasn't done a thing. He reordered some computer chip, but it won't be here until the 29th. I am at my wits end here.
 

Faztbullet

Supreme Mariner
Joined
Mar 2, 2008
Messages
15,589
Re: Mercury 225 offshore almost dies, then starts up again

Is it carbed or efi? If carbed it sounds TPI on carbs is defective or if EFI the fuel pump/s has a problem.
 

Bright

Recruit
Joined
Jun 26, 2010
Messages
5
Re: Mercury 225 offshore almost dies, then starts up again

What i can offer is the obviuos, check the bulb, fuel filter installed in the right direction, oil mixture is right or even if the oil pump is working properly, fuel pump diaphram isnt punctured and plug wires are in good order. i have the Mariner version and its doing the same thing plus some. When i find out more with my trouble shooting then ill post. Sometimes we over look the simple things.
 

Faztbullet

Supreme Mariner
Joined
Mar 2, 2008
Messages
15,589
Re: Mercury 225 offshore almost dies, then starts up again

List of items that can cause this and in order of what I would check first:
a) bad TPI sensor
b) bad engine temp sensor
c) misadjusted shift interrupter switch
d) defective ECU
If engine has a fair amout of salt water usage I would check all the ground to block and ignition plate also as this can confuse ECU...
 

jerogers

Cadet
Joined
Jun 22, 2010
Messages
7
Re: Mercury 225 offshore almost dies, then starts up again

thanks to all, Bright keep me posted.
 

jerogers

Cadet
Joined
Jun 22, 2010
Messages
7
Re: Mercury 225 offshore almost dies, then starts up again

All new coils put in on Tuesday and this guy still doesn't know what is wrong with this motor, now he has ordered a different ECU, but does not know when he will get it in. How do I get my boat away from him to find someone who knows how to fix it?
 

jerogers

Cadet
Joined
Jun 22, 2010
Messages
7
Re: Mercury 225 offshore almost dies, then starts up again

Here we are again, he put in the last three sensors and nothing helped. Yesterday he put in a new stator and will not return phone calls. I just don't know what to do anymore. Went to his shop last week and he is busy and I have to wait for almost an hour just to talk to him.
What is up with this motor? Any suggestions are appreciated.
 

That's Right

Recruit
Joined
Jul 22, 2014
Messages
3
I'm having the same problem with my 97 Mercury 225 offshore. What was the problem and how was it fixed. Please Help!! [h=1]Mercury 225 offshore almost dies, then starts up again[/h]
 

GA_Boater

Honorary Moderator Emeritus
Joined
May 24, 2011
Messages
49,038
Please start a new topic with your questions. This one is four years old and the OP has been gone that long. Thanks.
 
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