Gitty Up Loss

[Bobo87]

Okay for some reason my boat has decided to cop an attitude. I have a 2007 212 with a VP 5.0 GXI with DP. It used to run about 48mph at 5,000 rpms with wot it would go 5,500 rpms although I kept it under 5,000 as recommended by VP. Well this weekend she tapped out at 42 mph and 4,400 rpms but the main thing was the loss of hole shot. From a dead start it was as if only half the cyclenders were working. When wot to go it was also pulseating some once it got to full speed. Any ideas what could be wrong? Perhaps low pressure fuel pump? Just desperate and don’t want to not have it running right for the 4th.

[cmattj]

How does it idle.? They will drop cylinders when they can't hold pressure.And when you key on ( not running) are you getting a long wheezing whine from the engine prior to start. Those are some indicators that fuel system Is weak.

But without a a scann and fuel pressure check you may be guessing. You could try a fuel filter and see . Not knowing your maintenance history

No worries pal you have time to sort it out

[Big Block Power]

What Matt said. Does the boat stay in the water or is it trailered. Just saying to make sure nothing is wrapped around the props.
Change fuel filter first.

[Bobo87]

Thank you both Matt and BB. The boat stays on the water and had a through maintenace in March. Changed everything since I just bought it in January. I didn’t notice anything whining before startup but wasn’t really listening either. I’ll pay closer attention on the 4th. Just the usual beep beep beep (5-10 sec) for the fuel to follow be fire starting. When it is idling it sounds a bit loopy to me. You know when something is a miss but the wife doesn’t hear it. Although I have not had this boat long I do notice many performance differences between it and my past Cobalt 23LS with 8.1 GXi VP DP now that boat ran great! Thanks Harvey! I just keep telling myself this is the smaller motor but now I am able to see a real performance issue. I always run Non-Ethanol gas and figured I might try some fuel injector cleaner. Thoughts or preferences?
Is the fuel filter hard to change?
Anyone have a tutorial to share?
I am a visual learner.

[Bobo87]

Also, just checked the bill from last service and they did put in a new water/fuel separator.

[Silverbullet555]

Did you fill up recently? Bad gas?

[Ytmsn]

Yeah, I'd change the filter right off. A bad tank will ruin a brand new filter. Then go from there.

[Bobo87]

I have not filled up but am due. I always get gas from the same place (Non-Ethanol) but even that can be bad. I will try fresh gas and injector cleaner on Wednesday but still feel like it is something more. I hope that is it though.

[Bobo87]

How hard is to change the fuel filter? If it is under an hour job I would like to do it myself. That way I can still use it over the 4th holiday.

[Ytmsn]

It shouldn't take more than 5 minutes. Just screw the old one off. Pour a little fuel in the new one and spin it on hand-tight.

You may need a filter wrench to get the old one off. Then I always use it to give a little snug after hand-tightening.

It will be located on your fuel pump and look like a small oil filter. It should be fairly easy to get to and easy to change.

[Bobo87]

After looking at the VP manual it looks like there isn’t much to changing the fuel filter. Looks like an oil filter so guessing a oil filter wrench is what you are talking about Ytsman. What do you mean by “pour some fuel I tot he filter” before installing?

[Bobo87]

Okay after further investigation the fuel filter is the same as the “water/fuel separator” which was replaced in February. So what is the likelihood it has already gone bad?

[slideruleracer]

What did the pulseating feel / sound like? That could have been the engine implementing a rev limiter, which it will do in certain circumstances. Best thing to check fuel pressure is to get a fuel pressure gauge, they're not that expensive, and thread it onto the fuel rail fitting. Start the engine and see what it is reading. You could also have somebody watch while you accelerate to see if it drops as the engine revs up.

Was the engine cold when you lost power and had the pulsing or is it happening at any engine temp?

[Big Block Power]

Okay after further investigation the fuel filter is the same as the “water/fuel separator” which was replaced in February. So what is the likelihood it has already gone bad?

If you get bad gas real easy. It's 10 bucks . Quick and easy. Remove it. Fill it up with some good ole gas and lubricate the oring and screw it back on and go for a drive. Just like changing a oil filter back in the day.

[Bobo87]

BB - Thanks. It been a few years (decades) since I did my own oil change but I understand completely. Seeing as the filter was newly installed in February I think it should still be good. Right?