2001 Challenger 2000 with 240 Merc EFI

[rsatina2002]

Thank God.... I was able to start my engine for 2001 Mercury M2 240 gen 1..... I have my ECU rebuild through Simon motorsports.... still won't start, and I've figure out the culprit, it's the electric fuel pump in the VST and bought a new one..... very interesting to install.... noted leakage in the polarity area, fix it and noted a leakage again in the return fuel hose and fix it with proper clamp..... and finally the engine starts, idling at 1000 rpm with running water attached to it... after 3 mins engine starts with noted decrease idling sound of the engine and restart and fires again and stop after 2 mins with idling noted decreases from 1000 rpm to 900-800 rpm before it stops... I know the boat has an old mixture of fuel about 6 years ago and I didn't change the oil about 6 years ago per previous owner... My question is anybody knows if I needed to purge all old oil and fuel and my father put my fuel with addition 25 gallons and it was already combined with old fuel and I believe the abnormal idling of the boat and turning it off itself was through the old fuel and oil.... my plan is to extract old oil and oil fuel and add 5:1 mixture in the tanks and add new quiksilver TW3 oil in both reservoir and oil tank.... Any suggestions what I would at this time to improve idling.... I have test my boat in the water... It was my first time owning a boat and plan to test it it in the lake and after i'm planning to use it in the ocean.... Please give my suggestions what to do to improve idling and engine stability.... Thank you for your help in this forum, I really appreciate it....

 

[hivoltage98]

Yes. Purge everything. Try non ethanol gas. If the boat was sitting you’ll most likely need a carb rebuild since all the crap in the fuel will enter the carb system. Once you get some fresh oil and fuel into it then reevaluate it.
I also use sea foam but many people hav3 mixed reviews.

 

[Dr Honda]

This should be in the Mercury section. This is for the Rotax engines , and they are totally different. I will move it.


Next... if the fuel is 6 years old... then it needs drained. Putting fresh fuel on top of bad fuel does nothing other than make more bad fuel. So.. drain all of it out of the tank, drain the VST, and replace the filters.

The oil should be ok. But if you want to drain it... then that's fine. At least you will know what's in the system.

 

[Natrillius]

Hi All, I have a similar question minus the parts about fuel and oil. I just picked up 2001 challenger 2000, it is in wonderful shape, starts up on the first turn of the key....until today. I backed it down the ramp turned the key and it just cranked. It seems to fail to start when in the water only....pulled the trailer out turned the key and it started the second time. I am relatively new to this type of boat and simply need time direction as to where to start investigating. Thank you all for the help!

 

[Dr Honda]

You need to start your own thread, and not try to hijack this one.

 

[Natrillius]

Sorry, brand new to this my bad.