Gas vapor lock ...help

[Wish]

My good friend has a Malibu Echlan with symptoms of gas vapor lock. If I remember, this was somewhat common issue I think. Any DYI resolutions that can be done to remedy the problem?

[PurdueSkier]

What engine? If it has a vapor separating tank (vsp) I can help. I had this issue gir a couple years and finally fixed it

[Wish]

@PurdueSkier

I'm almost 100% sure it's this one.

 

[DW]

@Wish : That engine probably has a mechanical fuel pump, so vapor lock is not really that common with that setup. Probable causes as it sounds like a newish problem would be the fuel pump is getting a bit weaker due to age. To help, you can take a cold rag and toss on pump when it acts up, insulating the fuel lines helps and running the blower when you shut a hot engine off will keep the underhood cooler.

Ethanol fuel is not friendly for vapor lock on an older engine, in fact old fuel lines and rubber parts from the mid 90's are not compatible with ethanol fuel so those may need to be replaced and are contributing to the issue.

[vtmecheng]

Happens to my dad's boat every 5 to 10 years. His engine has a mechanical pump. Every time it's due to a weak pump. Swap it out and everything is great. Also agree with @DW, insulating the fuel lines around the engine helps.

[slvrbulit]

@wish try running your blower the whole time the engine is running and also let the boat idle for awhile before shutting it off after running it hard. It worked for me this summer when my boat was vapor locking.

[DkLkSkr]

Vapor Lock Pump Kit

Adding this fuel pump kit fixed my vapor lock completely on my '05. No issues since installing. I believe it is just a low pressure pump that pushes the fuel up the line instead of a fuel pump mounted near the engine that pulls the fuel. I'm sure others can chime in on the exact mechanics of it.

[PurdueSkier]

@wish what @dklkskr said. I did 2 things to fix my issue. I installed an auxiliary electric fuel pump right at the tank. This pressurized the fuel line from the tank to the engine where the mechanical fuel pump is. The second issue was related to the vapor separating tank that my engine has. If you have one, look at replacing the gasket and diaphragm inside the vst. The diaphragm acts as a 1 way valve allowing built up vapor to escape and bleed back to the front of the system. In my case the vapor lock was happening inside this tank. The diaphragm was installed backwards and wasn't working properly. Depending on the model of vst, determines which way it is installed. Once I bought a new kit and installed correctly I have had no issues for several years.