43L 190hp wont start HELP

When I turn the key the engine

When I turn the key the engine briefly starts for a second or so basicaly just at the point where I would stop turning the key and it stops smoothly. as if the kill switch was off but its not ive checkd sever times.
(its carburated)

new spark plugs
new cap and rotor (dry inside)
new fuel filter last year

Fuel pump isn't running. B

Fuel pump isn't running. Bypass the oil pressure switch and I bet it runs.

ok ill give it s shot today. &

ok ill give it s shot today. (not to motor smart i how do i do this?) if this is the case are they easy to replace

I had the same problem with my

I had the same problem with my mercruiser 165 It would only start when the key was turned for a breif second. I coulnt figure it out for the longest time then I looked at the wire on my ignition switch and a purple wire was undone so I hooked it up and she started right up and never had a problem again. Just look at your ignition wire first.

On my boat it is on the left s

On my boat it is on the left side of the block about midway down and in the middle from front to back. It has 2 wires attatched. Maybe a plug. If you just disconnect the wires and use a scrap piece of wire to jump the wires you will hear the pump run with the ignition switch turned on. It is easy to replace. If you have a manual it will guide you to the pressure switch.

"Seems to me that, if you have

"Seems to me that, if you have an electric fuel pump, check to see if you are getting 12 volts at the fuel pump first. Disconnect the harness at the fuel pump, connect a voltmeter, and then see if it goes to 12V when you crank. If not then the problem could be anywhere along the purple wire going from your ignition switch (key switch) to the back of the boat, where it ends up going through an oil pressure switch on the way to your fuel pump, among other things (like your ignition coil). The other thing that could be bad is your oil pressure switch, so if you aren't getting 12V at the fuel pump while cranking, jumper across your oil pressure switch as described above and retest.

If you are getting 12V, then reconnect the harness and feel your fuel pump while you have a helper crank your boat to see if it is buzzing (meaning that it's running) as you crank. If not, you have a bad fuel pump.

Of course, all of this assumes you have an electric fuel pump.

Lastly, are you *sure* you're getting spark? Get a spark tester at your local automotive store and test, just to make sure."

so its not the fuel pump. i ca

so its not the fuel pump. i can wire it right to the battery and here it running but still wont start. how much pressure is supposed to be on the fuel pump? ( i can plug it and stop it with my finger when i unscrew it out of the carb. i also tried a new ignition and didnt help. also all new plugs. when i took the air filter off i noticed it backfiring with flames coming out. could it just be my carb going bad on me? could it be a clogged fuel filter?

"running too lean, timing off,

"running too lean, timing off, burned exhaust valve, crossfiring plug wires or dost. cap arcing."

ok so i think it is my ignitio

ok so i think it is my ignition module. when i use a jumper wire from the positive on the battery to the purple wire (positive) on the ignition coil it will fire right up and run. does this sound like the ignition module or does the purple wire on the ignition coil run somewhere else?

There is a purple wire "I

There is a purple wire "I think" that runs from the coil to the tach. If the tach shorts out the engine won't run.Look to see if you get motion on the tach when you turn on the ignition.

"Ed: I think that wire is gray

"Ed: I think that wire is gray, but it's in the same circuit as the purple wire, as it's hooked up to the ignition coil along with the purple wire.

Nick: going off of what Ed said, try disconnecting the gray wire from your coil...the one that goes to your main barrel harness; not the one that goes to your ignition module."