Engine won't start

JohnP

I have a Rinker 270 2002 with a 350 mercruiser engine, the boat has been fully serviced during the course of the winter and have checked the engine and it won't start, I called in the agents and they could not find a fault, however they indicated the crank shaft sensor was not giving the correct reading and they replaced it.(The day they fitted the crank shart sensor for some reason the boat started but we went ahead with the replacement) The boat worked for about 3 weeks and again won't start

Black_Diamond

Make sure your shifter is in neutral. 
Top of your engine, right behind the throttle body is a red button/circuit breaker. Reset it by pressing it down. 

212rowboat

there's often a laynard 'dead man switch' on the controls, too, depending on how that rig is set up.  Make sure it's in running position. 

MarkB

I recall someone posting a few years ago that their deadman switch was corroded, so it wasn't making good contact.

John, does your starter turn, or is everything dead?

Weber

Is the engine turning over, or just not firing?

seadogs

Check the ignition cap and rotor. The rotor will burn through and will go to ground on humid days. I chased the same thing for weeks

JohnP

We have discovered that there was a problem with the air intake valve which was not registering on the computer