Hi guys
Most if you will have heard me banging on countless times about why the merc mpi won’t start, but turns over seemingly fine.
So just to prove a point this week (not saying it’s the case for all, but worth considering), on a lovely spring day and on a whim without the boat being touched all through winter...I connected up the hoses and fittings again...and backed the boat down the slipway...just on the off chance she would start and give me a nice day out on the water.
The battery (which is definitely too wee at 85ah and 550cca) hadn’t been charged since late November. But it seemed to show a quick crank at the turn of the key before launch....
anyway, I backed her in the water...turned the key and she turned over fairly vigorously and keenly...but didn’t instantaneously fire....until...I let go of the key, she kicked.
Now...as I’ve said a few times now...these things are so dependant on Amps and juice to fire the MPI system, that the very action of cracking the starter can and will cause a failure or refusal to fire them.....not until the instant you let the key go...then what happens is, the load taken by the starter, instantaneously drops and at the same time, the ecu all of a sudden thinks there now is enough power after all...and fires the engine. Symptoms of which are;
quick and normal cranking speed, but a bit of a cough or even a fire of the engine, on release of the key. A charged or new battery will sort this out !!
Anyway....enough of a rant from me...just saying...despite perhaps it not obviously being the battery and seemingly normal cranking, it might just be after all. Just make sure, before you start to empty the wallet in a spring time rush !!
happy boating all and enjoy this wee first sail hole shot from Sunday there !
https://youtu.be/037Q510UbJc
Most if you will have heard me banging on countless times about why the merc mpi won’t start, but turns over seemingly fine.
So just to prove a point this week (not saying it’s the case for all, but worth considering), on a lovely spring day and on a whim without the boat being touched all through winter...I connected up the hoses and fittings again...and backed the boat down the slipway...just on the off chance she would start and give me a nice day out on the water.
The battery (which is definitely too wee at 85ah and 550cca) hadn’t been charged since late November. But it seemed to show a quick crank at the turn of the key before launch....
anyway, I backed her in the water...turned the key and she turned over fairly vigorously and keenly...but didn’t instantaneously fire....until...I let go of the key, she kicked.
Now...as I’ve said a few times now...these things are so dependant on Amps and juice to fire the MPI system, that the very action of cracking the starter can and will cause a failure or refusal to fire them.....not until the instant you let the key go...then what happens is, the load taken by the starter, instantaneously drops and at the same time, the ecu all of a sudden thinks there now is enough power after all...and fires the engine. Symptoms of which are;
quick and normal cranking speed, but a bit of a cough or even a fire of the engine, on release of the key. A charged or new battery will sort this out !!
Anyway....enough of a rant from me...just saying...despite perhaps it not obviously being the battery and seemingly normal cranking, it might just be after all. Just make sure, before you start to empty the wallet in a spring time rush !!
happy boating all and enjoy this wee first sail hole shot from Sunday there !
https://youtu.be/037Q510UbJc
