Re: Mercruiser Engine Problem
 

easy way to tell if coil... when they go bad ..usually it because theres a short it gets hot expands shorts out totally dies till it cools then starts back up. when it stalls touch coil if very hot theres you problem.. thats the back yard way the other way is to use a dvm ( digital volt meter) and check the ohms resistance.

Re: Mercruiser Engine Problem
 

Seen a lose wire on the circuit breaker do that.Also a bad key switch.

Re: Mercruiser Engine Problem
 

A engine grounding problem can easily be the culprit. Don't spend money until you've made sure it is not a ground problem.

Re: Mercruiser Engine Problem
 

That symptom (surging at high RPM) can be a caused by several things, but I don't think the IAC motor is one of them. A few suggestions:

Check battery and engine power and ground connections as suggested above.

Check Knock Sensor and Ignition Control circuits (wires) and make sure that they are not touching any spark plug wires.

Check for trouble codes.

Check fuel pressure under load.


Dave

Re: Mercruiser Engine Problem
 

I agree with dave but surging isnt what he said, cutting out is granted its a fine line but with out running the boat have to go with what is said. and im not saying that thats what it is just saying check it. could be it along with fuel press coil ect. can sit here and give 200 reasons but have to go step by step till you find the culprit. thats why theres flow charts and short cuts but if not in front of you you can only say to check in order of elinination

and yes my spelling sucks

Re: Mercruiser Engine Problem
 

Look hotshot, first of all, I never said I'm always right. Second, you never said you were in a limp-home mode, so I assumed you weren't or you would have (should have) mentioned it.
Third, I'm trying to help you with my experience. If you think disrespecting me when I'm trying to help you is cool then go phuck yourself and everybody that looks like you.
Ed Cozzi

Re: Mercruiser Engine Problem
 

ok here we go first its not my boat read the post....

second, I dont survey boats I fix them....

third..... i THINK first before I tell someone something....

fourth.... after 25 yrs I think ive proboly been doing this longer then you....



if I wanted to be mean and dis you I would of told you to eat s*it and die

I have certs from merc, omc and volvo and you...???????



oh and no im not a hot shot just 42 yrs old been doing hp boats for a long time and no im not always right just not wrong often and dont like being put down when im not wrong if i am then go for it.. if your not 100% sure when you say something then say I think the iac only controls idle. dont mke it sound like you know 100% that im wrong when im not!!!!!!!!

I take alot of pride in my work and try not to be wrong

I dont survey boats

you do

do you want me to say more

Re: Mercruiser Engine Problem
 

I just realized that "Mr. trying to be clever," GoodT, didn't start the thread.

Well, here's my take on your suggestion about the IAC with the symptoms mentioned: YOU MIGHT AS WELL HAVE SUGGESTED HE TEST THE WINDSHIELD WIPER SWITCH!

It's punks like you that keep a lot of guys from posting here. Sarcasm has yet to fix any boat I've ever worked on.

Re: Mercruiser Engine Problem
 

Look, Punk, I'm 57 years old and have probably forgot more than you'll EVER know.
You had a lot of nerve disrespecting me. I am WAY more than a surveyor and always have been. I was already over the wet-behind-the-ears mode when I was 42. Hopefully this might happen for you.

Re: Mercruiser Engine Problem
 

Hello to all that took the time to answer me. I did do the fuel filter. I did check the fuel pressure but not under load just on the lift out of the water at idle. I did not change the coil yet. I will try and change the coil and then try to change fuel pump and see where that takes me. Please if you have any other suggestions please feel free in contacting me. THANKS AGAIN TO ALL.