I have a 2007 280 with 4.3 mercruisers....

[frdbrown00]

I have a 2007 280 with 4.3 mercruisers. It starts well and runs like a champ, but if I anchor or go to a dock and let it sit for awhile, it will not restart. It cranks and tries to run but sputters at abpout 400 rpms then slowly stalls. If it sits for longer than three or four hours, it starts and rune rough but able to get back to slip. First three trips we had to be towed back to marina. We changed distributor caps, and plugs, runs better but hot starting problem still remains. any suggestions? Downtown

[Hideout]

I have the mercruiser 6.4 and my aic valves needed replacing. Changed both out AND the croutons. My croutons were so fouled that hardly any air was getting to the intake. Solved my problem and she starts right up now with no low end cutout. Its a very easy fix and you can do both inside 30 minutes..let us know what you do!!

[Island_time2]

Sounds like your experiencing vapour lock in the fuel lines. It seems to be a common issue with these boats. There’s a Mercruiser service bulletin that addresses it. I started with the check valves in the cooling lines but I’m still getting the no start. I may try the auxiliary fuel pumps next

[Island_time2]

https://lookaside.fbsbx.com/file/99_07%20vapor%20lock.pdf?token=AWzS3zcu61a_VTi7kCKyjRzCGJxI7WGYdx3l9Dt6Gc6AjgqZ41iMOpMd7PnDRzHAJrIgRLFpD9jwyjBPgcN4jy_zTEOi0NY2wLAsBm28JUeEdeXObvaNul4aK_GaEIzZ63bot5mI2gU5lJ-59Q9XGx39CZ4j6f8pPNlWjQpnprE3Igd8zCZTsxGzb2W5BOEOEOPKjo9WumE2_2XT9kcsOrS3