Mercruiser 3.0 starting issues after suffering flat battery

[Walker600]

So I was out on my boat the other day, and everything was running smoothly all day, untill on my way home I stopped in open water to let my friend have one last go on the donut and the engine wouldn't start, just a clicking sound from the starter motor..... the alternator belt looked a bit loose so this may be the cause of the trouble but I can't be sure untill i fix the next issue.
I took the battery out and charged it and now the engine cranks over fine.

But now the engine wont start!!!

I'm defiantly getting fuel to the carbs because I can see it squirting in when I open the throttle, I've checked the kill switch and thats ok, and I'm defiantly getting electric down the HT leads but as of yet havent been able to confirm a spark, But as everything was fine prior to the flat battery I can't see why there should be an issue here. I've cleaned all the spark plugs anyway, and they all look in good condition.

Am i missing something..? This is my 1st boat so i'm just kinda feeling my way around it, Any advice from some seasoned veterans would be greatly appreciated...

Thanks for any help

 

[fat fanny]

Re: Mercruiser 3.0 starting issues after suffering flat battery

You are most likely gonna have to define what year and manufacturer or type of ignition to get more accurate information my 1st step would be to confirm spark and move on from there. Spark tester from harbor frieght $2.99. after that look into the stickies section @ the top of the forum a good bit of troubleshooting info there that is priceless.

 

[Don S]

Re: Mercruiser 3.0 starting issues after suffering flat battery

I'm defiantly getting fuel to the carbs because I can see it squirting in when I open the throttle, I've checked the kill switch and thats ok, and I'm defiantly getting electric down the HT leads but as of yet havent been able to confirm a spark, But as everything was fine prior to the flat battery I can't see why there should be an issue here. I've cleaned all the spark plugs anyway, and they all look in good condition.

Let's break the above down a little bit.
You may be getting fuel, and your problem could be it's flooded (Too much fuel) opening the throttle to wide open and cranking will usually clear up a flooded condition.
Your kill switch. Just checking to see that it's on doesn't tell you if it works or not. You need to turn the ign. switch to the run position, and check for power (with a meter) on the purple wire going to the coil.

I'm defiantly getting electric down the HT leads but as of yet havent been able to confirm a spark,

How do you know you are getting electric down the HT leads if you haven't checked for spark? That is going to be the only way of knowing.

To check for spark easily, remove the center wire from the distributor cap. Hold the metal end of the wire about 1/2" away from a clean ground and have someone crank the engine over. You should have a bright blue spark that easily jumps the gap.

Might want to put the below information in your signature.
Then we will always know what engine and drive you have when you ask a question.

Mercruiser 3.0L 0W043698
Alpha I Gen II

 

[Walker600]

Re: Mercruiser 3.0 starting issues after suffering flat battery

Hey, thanks for the advice and sorry for the late reply, It's been a bit hetic over xmas.

So, I confirmed the spark, but replaced the plugs any way and reset the gaps, and while I was at it I replaced the water separating fuel filter, Started up great!

Went out for a run today and the engine ran great, altho now I seem to be having an issue with overheating whilst underway. It rises up to about 180/190 while running at speed (probably higher but I throttled off) and drops fairly quickly as soon as I slow down, Only to repeat this process under the same conditions.

I'm thinking of starting by looking at the thermostat and impellor? Does this sound logical to you guys?

O, and i've added that information to my signature.

Many Thanks

 

[Don S]

Re: Mercruiser 3.0 starting issues after suffering flat battery

The impeller is the first thing you look at on a marine engine. They can be damaged in many ways.