Challenger 2000 240EFI M2 Fuel Theory
I recently joined the forum since I purchased a 2001 Challenger 240EFI M2 boat a few weeks ago. First, I can't say enough about the wealth of information on the forum. It has helped me to get the boat ready for the season with all of the detailed information...
After reading every thread on the 240EFi motor, I have some input and a theory on some of the damaged engine situations with melted pistons (few examples are listed in this forum). This could relate to any engine as well... I believe the main cause is the fuel people are using. There are many ways to end up with insufficient fuel in the boat that could be contributing to these engine failures. I have many friends with 700+ horsepower I/O engines that have recently had the same problems.
First, the marinas that sell fuel are never consistant in my opinion. I have seen bad fuel from some of the most reputable marinas around. The issue is the turn around of the fuel and how long it sits in the tanks. By the time it is purchased you could already be in a problem situation... Fuel can lose as much as 1 point of octane each month when stores in plastic containers...Which I know is the method for the Challenger tank... Imagine leaving 87 octane fuel over the winter then running in the spring. Even with additives, the full could lose substantial quality by springtime..
So, how does that impact the engines? Detonation or pre ignition.. That is the leading cause of piston failure. It really comes down to fuel, oil mixture and lean condition. The most simple reason is that the fuel burning in the motor is poor quality. Compound this with fuel that was purchased from a marina that sat in the tanks for months and you have a blown $5k to $12K engine.
This article was very good at describing the situation with detonation and the use of poor fuel www.marinesurveyor.com/boatpokers/data/piston.pdf
I know that I plan to start the season running 93 octane fuel from a normal busy gas station. I plan to run 93 for the first two tanks at the begining and end of the seasons. At least storing 93 octane over the winter would give you a little head start in the spring when you are out for the first run...
I would be interested to read any thoughts or comments on this theory... It is nearly impossible to hear detonation in a boat due to all of the noise and wind so I think this would be the main concern for me...
Dave
I recently joined the forum since I purchased a 2001 Challenger 240EFI M2 boat a few weeks ago. First, I can't say enough about the wealth of information on the forum. It has helped me to get the boat ready for the season with all of the detailed information...
After reading every thread on the 240EFi motor, I have some input and a theory on some of the damaged engine situations with melted pistons (few examples are listed in this forum). This could relate to any engine as well... I believe the main cause is the fuel people are using. There are many ways to end up with insufficient fuel in the boat that could be contributing to these engine failures. I have many friends with 700+ horsepower I/O engines that have recently had the same problems.
First, the marinas that sell fuel are never consistant in my opinion. I have seen bad fuel from some of the most reputable marinas around. The issue is the turn around of the fuel and how long it sits in the tanks. By the time it is purchased you could already be in a problem situation... Fuel can lose as much as 1 point of octane each month when stores in plastic containers...Which I know is the method for the Challenger tank... Imagine leaving 87 octane fuel over the winter then running in the spring. Even with additives, the full could lose substantial quality by springtime..
So, how does that impact the engines? Detonation or pre ignition.. That is the leading cause of piston failure. It really comes down to fuel, oil mixture and lean condition. The most simple reason is that the fuel burning in the motor is poor quality. Compound this with fuel that was purchased from a marina that sat in the tanks for months and you have a blown $5k to $12K engine.
This article was very good at describing the situation with detonation and the use of poor fuel www.marinesurveyor.com/boatpokers/data/piston.pdf
I know that I plan to start the season running 93 octane fuel from a normal busy gas station. I plan to run 93 for the first two tanks at the begining and end of the seasons. At least storing 93 octane over the winter would give you a little head start in the spring when you are out for the first run...
I would be interested to read any thoughts or comments on this theory... It is nearly impossible to hear detonation in a boat due to all of the noise and wind so I think this would be the main concern for me...
Dave
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