2001 Merc 250 EFI stumbles/misses out of the hole...

[phaster]

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<!-- / GOOGLE AD CODE ADDITION END --> <!-- message --> <!-- BEGIN TEMPLATE: ad_showthread_firstpost_start --> <!-- END TEMPLATE: ad_showthread_firstpost_start --> <!-- google_ad_section_start -->Hi folks,

I have a 2001 Mercury 250 EFI that I am having an issue with. It idles fine, free revs fine, and feels pretty good once the boat is on plane BUT it makes no power when trying to get the boat out of the hole. If I accelerate VERY slowly I can sometimes get her up... but 99% of the time she simply sputters when trying to get going.

Compression is in the 120's in all cylinders, brand new champion spark plugs (which look fine after running), brand new fuel filter on the motor as well as inline inside the boat. Checked all plug wires and they seem fine. Could it be a bad coil(s)? is there any way to test them with a multimeter? Any other ideas?

As a side question, can anyone recommend a good shop in the Miami area that can hook up the motor to the diagnostics so I can see what is going on?

Thanks in advance!!!

[vnemous]

Has it always done this with the same prop or has the prop changed and the problem start? What prop are you running?

[rmpenton1]

Unplug the harness going to the stator and test every wire to ground for ohms. If any are open then your stator is bad. The DDT machine won't tell you much. You can check your tps with a multimeter it should be .95-1.0 volts with the throttle close.But I would look at the stator first

[phaster]

vnemous, I have a 4 blade mirage 22 and i have also tried a 3 blade 21 with the same results. Same issue with both props.

rmpenton1, I will see if I can test the stator like you suggested and get back.

Thanks so far guys.

[phaster]

I just checked the 6 wires on the stator to ground. 3 of them have similar readings and hold steady. One is about twice as high as the others and two are a bit lower. One does not seem to hold steady. What type of ohmage am I looking for?

Thanks!!

[rmpenton1]

I am away from home right now so I can't tell you for sure. If no one answers the question before Monday I will let you know. I know that if one is open then it's bad.

[Shaun Torrente]

They should all read 600-1k ohms depending on temp.... they should all be real close... i will be more than happy to check it for you but i am flying out to go racing tommorrow afternoon so it will have to be in the morning

Shaun

[phaster]

Shaun, you are saying they should all read 600-1000k Ohms when each of the 6 wires is tested to ground? Where are you located?

Thanks again.

They should all read 600-1k ohms depending on temp.... they should all be real close... i will be more than happy to check it for you but i am flying out to go racing tommorrow afternoon so it will have to be in the morning

Shaun

[phaster]

Ok, I just tested them again. This is with the motor cold and off....I am using a K-Ohm meter.

Looks like two of them are off (one of them is WAY off). Also, the one reading 7.5 does not seem to hold steady, the reading moves around for some reason on that one. Does this mean the stator is bad? Any way to fix or does it just have to be replaced?

7.5 fluctuating
1.125 solid
1.020 solid
.984 solid
1.083 solid
2.588 solid

Thanks!!

[Shaun Torrente]

I'm in homestead but i am heading to bird road and 60th ave this morning for service call then dinner key marina... i have a good used stator... #6 is bad

Give me a call i will throw it in the truck

Shaun
786.229.5801

[phaster]

PM, sent Shaun...

Hopefully it will be the stator causing the problem...I will post back results.

Thanks again for all the input guys...MUCH appreciated.

[rmpenton1]

Good luck With your race Shaun. Shaun is a good person to buy from. He Helped me out with my 225. The stator should get you up and going