how did you fix your vapor lock problem?

[volfo]

Any suggestions on what you did to fix your vapor lock problem would be appreciated. Considering: regular course of stabil and initial dose of heet water remover (even though I don't use ethanol gas I do get it from marina and could be poor quality); running blower constantly; possibly replacing fuel line between pump and filter with larger diameter, straighter run and insulating it.

Leaving hatch open on direct drive every time we stop to swim or eat lunch in boat is just not a workable thing - no room at all in the boat plus kids could fall into hot engine compartment.

Please reply if you've had vapor lock issues and you've been able to tame them.

[KG's Supra24]

I use gas without ethanol and do not have any problems. It is bought on land at a high turnover location.

I have used gas with ethanol less than 3 times and had vapor lock one of those times.

I believe some add another fuel pump? but above is about all the help i can be.

[volfo]

thx. I called indmar and they confirmed I already had 2 fuel pumps and can't add a 3rd on this configuration (320 hp throttle body injected Assault). Keep the boat on a lift at marina and am kind of stuck to buy the marina gas. They swear there is no ethanol in it and so I'm thinking there may be a bit of water in it. Thinking the cure is stabil / heet for that.

Plus, I'm definitely going to run blower and work with a mechanic to re-run the fuel line in a larger diameter and insulate it.

[sandm]

vapor lock here a couple of times. I just make sure and run the blower during every run. goes like this:
-start the blower
-start the boat
-enjoy
-turn boat off
-turn blower off after a minute or so.

has cured almost every time, but the one time it did happen after that, I just took a cup of water, dumped it on the fuel pump located next to the motor and it fired right up..

I don't take the time/energy to locate non-ethanol fuel, as I think it's going to get harder as time goes on, and buying seafoam/stabil is somewhat expensive..

[rdlangston13]

So you are supposed to run the blower all the time? I thought it was for sucking out possible fuel vapors right before you start the engine?

[sandm]

it pulls some of the heat out of the engine compartment. heat is the enemy when you think of vaporlock. fuel that has ethanol has a much lower boiling point than non-ethanol fuel.
you have a small block engine in an enclosed environment generating lots of heat and that heat has nowhere to go. the fuel lines/pump absorb that heat, you turn the boat off, the gas stops flowing and now it starts converting to vapor. when you start the boat up, the pump can't pull the gas.

running the blower has helped me. only happened once since then. no guarantees, but it's a cheap part and really can't be heard much over the engine.

[volfo]

I have always just run the blower to make sure no gaseous fumes in the engine compartment at ignition, but they are telling me to run it continuously. My vapor lock doesn't happen when I just shut the engine off for a few minutes - it happens when the engine is off for an extended period of time - like anchoring to swim, going to a marina to eat lunch - when the boat is off for 45 minutes to a couple hours and sitting in the hot TN sun. Happened twice recently - both days where it was around 95 outside.

They are saying run that blower the whole time the boat is off. Gonna try it. Also going to be using some fuel additives regularly to make sure no water / ethanol in gas.

Any other suggestions? Thinking of paying to have a larger diameter fuel line run with a straighter line, and insulated too.

[cab13367]

Since you have a DD but don't want to fully open the clamshell when you anchor to swim, perhaps you can devise a way to partially prop it up to let the hot air escape. Definitely run the blower all the time that the engine is running if it's a hot day.

[wolfeman131]

volfo - couple of things that I have tried/used that have seemed effective and an idea I plan to look into this summer:

1) marine stabil
2) run blower (as already stated)
3) open engine compartment and plug in one of those 12v automotive fans to push fresh air in
4) cooler with cold water. pour cool water on fuel filter.
5) cooler with cold beer. drink beer if 1-4 fail.


planning to install in-line blower fans on the forward fresh air intakes on the blower switch so that I'm pushing fresh air in as well as engine compartment air out.

[murraymoomba]

I mounted a blower pushing air directly onto the fuel pump, seems to help. I leave it on all the time and also leave the factory blower on too. One pulling cold air in and one pushing hot air out.
I also put 4 clothes pins on the fuel lines (old trick from back in the day)around the fuel pump.