suzki df40 (2003)

[kodom213]

My 2003 Suzuki df40 was running great until about a week ago when I was running at about 5800 rpms and the out of no where they dropped I proceeded to give it more throttle and that did nothing. The rpms came down to about 800-1000rpms while still at full throttle and it was running very rough like it was not firing on a cylinder. It then died and I couldn't get it to crank up. I gave it throttle and tried cranking and I successfully fired off but still ran very rough and then died. it will turn over and I can tell it tries to fire but wont crank. the high pressure fuel pump was replaced 3 years ago. the spark plugs are a year old. all the maintenance and repair were done at a certified Suzuki dealer. Not sure what is wrong but from what I have read it could be a cracked piston or an injector issue.

[redlowrey]

It would have to drop two cyls to bring the rpm down that low, pull the plugs out and look at the condition of them, wet dry or otherwise, one coil may have failed, that will drop two cyls. If you can raise the warm up leever all the way and try and start it, if it starts pull the leads off each cyl and find which ones are missing. Check and make sure you have no water in the primary filters.

[briscoe]

Water separator filter

I had an off brand water separator filter I skipped changing one season. I idled my motor occasionally through our mild texas winter. Never ran it till spring. Owwie, my water separator was all rusted on the inside where the gasoline passes through filter. Valuable lesson, change that sucker every year.

[kodom213]

It would have to drop two cyls to bring the rpm down that low, pull the plugs out and look at the condition of them, wet dry or otherwise, one coil may have failed, that will drop two cyls. If you can raise the warm up leever all the way and try and start it, if it starts pull the leads off each cyl and find which ones are missing. Check and make sure you have no water in the primary filters.

When it first happened it fired off but didn't run. I pulled the warm up lever all the way and it started and ran but very rough and i couldn't limp back to the ramp cause it would die very quick. I checked the error code today (3-2) which is the map sensor and contacted my local Suzuki mechanic that has all the history with the motor and they said it it may possibly be something to do with the valve setting in the engine, but I will pull the coils off and check the plugs even though they were replaced just over a year ago. Thanks for the feed back!!

[kodom213]

I had an off brand water separator filter I skipped changing one season. I idled my motor occasionally through our mild texas winter. Never ran it till spring. Owwie, my water separator was all rusted on the inside where the gasoline passes through filter. Valuable lesson, change that sucker every year.

That could very well be part of the problem since mine is rusted on. About two months ago I was doing simple service on it like corrosion prevention and checking filters and I figured before spring came I would change the fuel water separator and come to find out its rusted on pretty good. I tugged on that stupid thing to the point I thought I was gonna rip the mout off the boat.