Please help!!!!!!!!! Engine won't start

[newowner1]

I have a mercruiser 5.7 v8, 300 hp. After this winter, i had to change both batterries. Today i installed the new ones, turned the key and the engine started immediately. It ran nice and sounded good for about ten seconds then quit. I tried for several minutes, (about 20 min.) to start it again. It never will. It will turn over but does not sound like it wants to fire again. Does anyone have any suggestions, please. Thanks

 

[the man]

Re: Please help!!!!!!!!! Engine won't start

too many options to list. but the first that i would try would be water in the gas and /or bad gas (after sitting all winter), fuel delivery, and /or corrosion in the ignition system.

 

[Bondo]

Re: Please help!!!!!!!!! Engine won't start

Ayuh,... It takes Fuel, Fire, 'n Compression, All at the right Time...

Yer missing 1 of the 4, 'n Only you can See which 1...

 

[Don S]

Re: Please help!!!!!!!!! Engine won't start

I have a mercruiser 5.7 v8, 300 hp.

That's not really enough information to help you.
Year, model number, SERIAL NUMBER is best, is the information we need to help you.