2007 MerCruiser 4.3 Won't Start

[Xelaw]

Hi all,

I can't get my '07 MerCruiser to start. It struggled then finally stalled out when I was running it last. It sputtered a lot but would not pick up. Now I can't even get it to start at all. I changed the fuel filter and oil (it was pretty low), but that didn't help. The engine turns over and there is a spark coming from the coil. I can hear the fuel pump running every time I turn the key. I've only dealt with fuel problems on carbureted engines before, so I don't know the best way to check fuel for this motor. Where do I go from here?

 

[achris]

Re: 2007 MerCruiser 4.3 Won't Start

Throw a bit of petrol down the intake. If the engine runs momentarily then you have a fuel problem. Best to check the codes on the ECU to see if it has logged a problem.

 

[Xelaw]

Re: 2007 MerCruiser 4.3 Won't Start

Thanks, I got it going with some starting fluid, but it sounds like crap and stalls immediately when I move it to high idle. The gas in there isn't too old, 2 months max and it had StaBil in it.

I don't have a way to check the codes on the ECU.

 

[Xelaw]

Re: 2007 MerCruiser 4.3 Won't Start

I SeaFoam'd it and it sounds good now. Also, I think I was mistaken...it has a carb not EFI.

 

[Xelaw]

Re: 2007 MerCruiser 4.3 Won't Start

After testing it on the water, it stalled out and I couldn't get it to start again. It fires a little bit though. I'm sure I can repeat the above procedure and get it to run at idle again, but it looks like I have to do more. Where should I go from here?

 

[Don S]

Re: 2007 MerCruiser 4.3 Won't Start

If all you did was seafoam it and use starting fluid, then you didn't fix anything.
Have you changed the water separating fuel filter and check for water in the old filter?
Post the serial number of your engine so we can see what you really have.

 

[Xelaw]

Re: 2007 MerCruiser 4.3 Won't Start

I did change the fuel filter. Serial number is 1A050562.

 

[Don S]

Re: 2007 MerCruiser 4.3 Won't Start

You have the TKS carb on there, do you pump the throttle a time or two to start or just leave it at idle to start?

 

[Xelaw]

Re: 2007 MerCruiser 4.3 Won't Start

I pump it a couple times.

 

[Don S]

Re: 2007 MerCruiser 4.3 Won't Start

Try this, without touching the throttle, crank the engine over for a about 10 seconds. Then shut the key off.
Remove the flame arrestor disconnect the throttle cable from the carb linkage, and pump the throttle linkage to WOT and back a couple of times and see if gas squirts 2 streams into the throat of the carb from the accelerator pump.

 

[Xelaw]

Re: 2007 MerCruiser 4.3 Won't Start

The carb was fine. Problem was lots and lots and lots of water in the gas tank.

 

[Bondo]

Re: 2007 MerCruiser 4.3 Won't Start

The carb was fine. Problem was lots and lots and lots of water in the gas tank.

Ayuh,... That'll do it,...

Water don't burn so good...

That's also Why ya should Inspect the fuel filter, instead of Just replacin' it...

 

[Xelaw]

Re: 2007 MerCruiser 4.3 Won't Start

It's quite odd though. I always use StaBil and I fill the tank on my way back home so it doesn't sit partially full. I usually use the boat at least every 2 weeks, this time it had sat for maybe 6 weeks. Oh well, guess I'll stick with ethanol free gas from now on.

 

[Don S]

Re: 2007 MerCruiser 4.3 Won't Start

If you had LOTS and LOTS of water, it's not from the type gas you are using, more likely water is getting into the tank, maybe the place you bought gas had water in their tank, or your fill cap leaks, or the vent allows water in, or _______________ ?

 

[Xelaw]

Re: 2007 MerCruiser 4.3 Won't Start

It was probably a half gallon to a gallon.

 

[Don S]

Re: 2007 MerCruiser 4.3 Won't Start

It was probably a half gallon to a gallon.

That's not ethanol. Look for the other problems.

 

[Bondo]

Re: 2007 MerCruiser 4.3 Won't Start

It was probably a half gallon to a gallon.

Ayuh,... That's Not condensation, that's intrusion...