Boosted502

If it's vapor lock is there anyway to avoid it? Run the blower all the time maybe. So annoying that the boat runs great then out of no where it wants to act up, then runs fine again.

mike tkach

iTrader: (3)

do a search on vst problem,s.you will find ton,s of information about it and how to cure the problem.

BUP

iTrader: (9)

Also some of the biggest common problems with GEN II cool fuel vapor locking is weak fuel pumps and NO ONE ever completely cleans off and reapplies the heat transfer compound on the heat shield against the fuel pump.

If ALL Merc EFI / MPI engines vapor lock from brand new to many other engines with 2 and 3 year warranties MERC would have been broke from vapor lock claims alone. Certain engines did get the boost pump kit added for GEN II cool fuel apps. This help as well for the engines that vapor locked from the start.

Also poor venting of the engine compartment increases vapor lock issues. Also many people pack their engine compartments with a lot stuff in which makes venting and incoming fresh air worse

The VST did vapor lock especially as it aged and or had its own problems. It was only around for 3.5 / 4 years as Merc had to come out with a better system.

Gen II and GEN III cool fuel systems are still on Merc products currently - and they are install on catalyst system engines, so talk about heat producers and in my area its all E 10 gas and 100 to 110 degree temps and very very warm water temps. These engines run all day, all weekend without vapor lock period..

I worked on 236 boats for 2016 and NOT one boat customer of mine experience any form of vapor lock. Not one. Maintaining systems with the boat and engines is another key. Also all these boaters use land gas in which is all E 10.