Vapor Lock?
 

Ok Guys...Help!

2000 Sea Ray with 5.7TBI engine. Boat start and runs fine. It will run all day at 170 degrees. Power at all rpm ranges is ok. When i drop anchor and sit for 30 minutes, the boat will not start., It has ignition, spark at plugs etc. If the boat sits for 60 to 90 minutes it will start and run fine. I called Marinemax and they told me this has become a common problem since ethanol was introduced last July. The fis is a booster pump in fuel line. Any one else having this problem and is a secondary pump the right fix? thanks

Had same problem with elec fuel pump on my 500EFI.
discovered that armature was heat soaking in fuel pump and locking up. Replaced with new electric pump and issue is resolved.

Check out this Merc service bulletin. Some good info on vapor lock.

http://www.boatfix.com/merc/Bullet/99/99_07.pdf

Dave

Some more evidence that ethanol does not belong in marine fuel. You won't be finding it in AV Gas. This stuff is garbage. It is also leaning out engines due to the difference in it's stoichiometric air fuel ratio. BBB

Reid vapor pressure @ 100 F PSI is 8-10 Gas
Only 2.3 in Ethanol
Latent heat of vaporization in Gas 900 BTU/Gal 150BTU/LB
" " ETHANOL 2378, 396 respectively.

Could this help explain it ? BBB