03' Captiva 212 5.0 Merc - Wouldn't start for 40 min, then starts

[WeekendLaker]

Hello All,
New to the forum,  recently discovered it doing some searches on my Captiva.  Tons of info on here and friendly people so I thought I would sign up.
Recently we took our boat out for a Saturday on the lake , a nuclear powerplant cooling lake, which is the same lake we boat in 90% of the time. Instead of getting gas at a gas station we opted to fill up at the Marina in the morning. We took a loop around the lake and then anchored for awhile to have lunch and chill out. Around 3 we went from the cool side of the lake to the warmer side, close to the discharge, and decided to anchor in a cove. As we were anchored I noticed we started to drift in the cove so I pulled up anchor to reposition and re-anchor. THis was about 10 min after we arrived at the cove. As I went to start the engine it would turn over but then die. Then eventually it would not turn over. THen I would disengage the drive and put the throttle at 3/4 and it would run but as soon as i backed it back down it would die again. Then eventually it wouldn't turn over no matter what I did.  So we sat there for 40 min and I tried it again and it started up no problem.  We took it back to the ramp and loaded it.
The 5.0 Merc is fuel injected (MPI). I took it to the mechanic and he hooked it up for codes and there were none. He said he highly doubts vapor lock with a MPI engine such as this one, I even brought up the warmer water from the lake might not cool the engine as fast. The IAC valve was replaced last year and is still working fine. This was only the second time we had it out all season. The Mechanic put it in his tub and ran it all morning to try and recreat the scenario and the boat ran fine.



Anyone experinced anything similiar or have any thoughts?  Bad Gas? Not taking it out enough times in the season?

Thanks in advance!

[cettialpha6]

This was only the second time we had it out all season. The Mechanic put it in his tub and ran it all morning to try and recreat the scenario and the boat ran fine.

Anyone experinced anything similiar or have any thoughts?  Bad Gas? Not taking it out enough times in the season?

I would agree with your suspicion of bad gas. You say this was the 2nd time all season, Do you use fuel stabilizer in you gas tank for long idle times? Did the boat sit for more than 60 days? How much fuel was in it before you filled up at the dock? I  once had similar problems with my old boat, it was a 05 212, just by chance. I ran the tank down low at the end of the season and it ran like crap. fyi,-----   Art

[WeekendLaker]

Thanks Art,  we had it winterized last year by the same mechanic and then put into storage.  First time out ran like a charm.  The second time was probably 30-40 days after the first.

I will try the fuel stabilizer.  I beleive I am going to take it out and cruise the lake until it runs dry then go fill it up with fresh gas.  We had a little one this year and not much time for boating this season, but I can't wait until she get older,  I ams sure she will love it.

[alswagg]

Vapor locking,  plain and simple,  just because it is MPI does not mean it cannot vapor lock,  How warm was the water?  The fuel pump is cooled by incoming sea water.  The fuel does not return to the fuel tank.   Ethonal fuel will vapor lock much faster than traditional non ethonal fuel.  Allan