Honda BF150 cold start issues.

[johnf1951]

I have a pre2010 engine with 250 hours on it. No carbs, all electronic. I just bought the boat used. The engine is very hard to start when cold but runs fine and restarts easily once warmed up. I have changed all fuel filters, fuel line, anti siphon valve and drained and replaced all of the fuel. This engine has always been run on ethanol gas. Any other suggestions?

 

[jgmo]

Hi,
Just a guess but this sounds like an engine temperature sensor issue to me.

The problem is proving it.

Without knowing the electrical values of the sensor, simply checking it with a multimeter can't be done with any accuracy.

You may need to have a shop hook up the Dr.H diagnostics software to find out what the sensor is reporting to the ECM.

If it's reporting too high a temperature during cold start, the computer won't command a rich enough fuel mixture to fire the engine.

It's also a good practice (when using the diagnostic tool) to compare the engine temperature reading to the Inlet air temperature reading and see that they read close to each other when the engine is cold and compare those readings to actual ambient temperature.

Good luck.