Mercruiser 3.0L will not Turn Over

[Racer57]

2007 3.0L Mercruiser ran well all last summer. Last used it in September 2015. Tried to turn it over in early December and when I turned the key, just heard the starter clicking. All accessories worked OK, including power trim and tilt so I just assumed the battery was weak. Charged it with two separate chargers, same result so I figured the battery was just dead. I bought it new in 2011, so that could be true.

Purchased a new battery today. Same result. Starter solenoid just clicks, but engine will not turn over. All accessories work, so there is juice available.

Any ideas?

 

[bajaunderground]

If the solenoid is clicking...

Go through all your electrical connections (even the new battery). Often times loose connections build up enough corrosion to hinder the amount of juice needed to kick-over the starter. After all that's checked, make sure you're getting the juice you think you're getting, load check your battery (Autozone, O'Reillys' will do it for free)...if those all check out, pull the starter and have it checked (same traffic, Autozone, O'Reilly's)...they can check it out of the boat, maybe even in the boat?

Good Luck!

~Brett

 

[Scott Danforth]

You have a bad connection somewhere. Start at the battery and clean each and every connection to shiney metal (so clean you can eat off them).

Your old battery was most likely good

 

[Mercruiser420]

Can you turn the engine over by hand?

 

[tpenfield]

Remove the spark plugs and see if the engine will turn over . . .

 

[Bt Doctur]

where do you live and did you winterize it or atleast drain everything?
was the starter ever underwater?
are all the cable connections clean and tight and NOT green?
is the oil in the drive ?

 

[fishrdan]

Are you hearing a solid "thunk" as the started engages the flywheel, but the engine does not turn over. OR, just a click when you turn the key?

There are 2 solenoids in the start circuit, the slave solenoid and then the traditional starter solenoid. If your slave solenoid is clicking and not energizing the starter solenoid, the slave solenoid could be bad (wouldn't be the first). Jump the 2 big terminals of the slave solenoid momentarily to see if the starter (and starter's solenoid) works. I have started my engine with a pliers shorting out the 2 big terminals of the slave solenoid, to get home when the slave solenoid died...