Fuel Pump Vapor Lock Issue?

This happened twice over the weekend. After sitting for an hour or so in the nice 105 degree weather, I would fire up the boat and get on plane or even less than plane and the boat would bog down as if I pulled off the throttle. I would then pull back to idle and try again and it would run fine. Also, this happened after we re-fueled at the marina. I am thinking vapor lock, but I thought that is when the boat can't start after sitting for awhile in the heat. This is on a '06 Supra 21V when they were known for having vapor lock issues.

back in the day, vapor lock would render us dead on the water. boat would not start.
we found that to prevent, we ran the blower nonstop while on the water. never had an issue after doing that. figured blowers were cheaper than the secondary fuel pump kits that were being peddled at the time.

not sure what would be driving your issue but if hot enough, maybe the fuel is vaporizing along the way and causing issues.

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Originally Posted by sandm

back in the day, vapor lock would render us dead on the water. boat would not start.
we found that to prevent, we ran the blower nonstop while on the water. never had an issue after doing that. figured blowers were cheaper than the secondary fuel pump kits that were being peddled at the time.

not sure what would be driving your issue but if hot enough, maybe the fuel is vaporizing along the way and causing issues.

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That’s solid advise. We also would put a wet rag over the fuel pump to cool it quicker if it locked out. I later also wrapped my fuel lines in that heat shield stuff too. Blower plus that wrap and I’ve never had a problem.

This stuff;

Design Engineering 010403 Heat Sheath 3/4" I.D. x 3ft Aluminized Sleeving for Ultimate Heat Protection https://www.amazon.com/dp/B000E267M4..._OIodFb6Q2W4VH

We get vapor lock with our 07 lsv from time to time. We were in Lake Powell last week and it was 110. I think i got it at-least 3 times. If the engine has been running hard and then sits for more than 30 min or so the heat in the engine compartment is crazy hot. If i am going to float for a while i either have to run the blower or open the engine lid to let the heat out. When i do get vapor locked i take a bottle of cold water and dump it on the fuel pump and it fires right up. It's an easy fix if you get stuck.

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Originally Posted by 996scott

We get vapor lock with our 07 lsv from time to time. We were in Lake Powell last week and it was 110. I think i got it at-least 3 times. If the engine has been running hard and then sits for more than 30 min or so the heat in the engine compartment is crazy hot. If i am going to float for a while i either have to run the blower or open the engine lid to let the heat out. When i do get vapor locked i take a bottle of cold water and dump it on the fuel pump and it fires right up. It's an easy fix if you get stuck.

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^^ exactly what I do with my 07 LSV.

Can a bad fuel pump cause vapor lock:confused::)?

How to Avoid It. The most common failure of high flow fuel systems is cavitation, or “vapor-lock”.

Oh man blast from the past. We took the 2008 OBV for a return trip to Norris (First time back in 6 years) this past week and sure enough after running her hard in 95 degree weather she wanted to sputter just about the time a storm was blowing in. I reached down into my Moomba forum memory bank and poured some cold water over the fuel pump and she ran like a champ! It was good to let this old fun boat stretch her legs again.

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Originally Posted by skiyaker

Oh man blast from the past. We took the 2008 OBV for a return trip to Norris (First time back in 6 years) this past week and sure enough after running her hard in 95 degree weather she wanted to sputter just about the time a storm was blowing in. I reached down into my Moomba forum memory bank and poured some cold water over the fuel pump and she ran like a champ! It was good to let this old fun boat stretch her legs again.

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See! This forum saved one person's a--.