Starter not turning over. 260 mercruiser

[kev301sam]

I bought a project boat and it has a 260 Mercruiser. When I turn the key the solenoid above the starter just clicks. The power wires coming from the solenoid to the starter has power but doesn't seem to be engaging the starter. Just clicks from the solenoid. Where should I start to get this fixed?

 

[Bt Doctur]

The engine is seized, the starter is seized, the starters solenoid is bad, the outdrive is seized or the battery cables are dirty

 

[kev301sam]

So where do I start to trouble shoot the problem? This is my first boat and I'm just learning

 

[Bt Doctur]

260 merc, guessing you have the 260hp GM v8 motor and a Alpha drive.If the drive is attached, check the oil level and condition by removing the top plug and see if the oil level is at the threads or just slightly below, you can check with a blade of grass.. loosen bottom plug slightly and see what runs out.
Check the oil level in the engine, if high suspect water in the crankcase.
Remove the starter and have it bench tested.
If you can locate a T bar or a old input shaft and have it welded to a T bar.Remove the drive and insert T bar and try to turn engine by hand.
If no movement at all, remove the spark plugs, check for rusted tips. Insert thin plastic hose in plug hole and suck gently looking for water in the cylinders

 

[kev301sam]

Ok, The motor has been rebuilt and not fired up yet. I'm just trying to get it all hooked up and figure it out which is turning out to be much more involved than I thought.

 

[Bt Doctur]

So the drive is not installed yet?

 

[kev301sam]

Drive is hooked up. Need a piece for carb to hook fuel line up and some work on trimmer pump which has been wired incorrectly. Which I need a wiring diagram for.

 

[Bt Doctur]

http://www.boatfix.com/merc/Servmanl/6/6C5R3.PDF power trim and tilt
http://www.boatfix.com/merc/Servmanl/16/16F4R2.PDF wiring

 

[G_Hipster]

So where do I start to trouble shoot the problem? This is my first boat and I'm just learning

Start with making sure the engine isn't seized and a known good battery. Charge it up and get it load tested.

 

[tpenfield]

If the fact that the engine is in a boat seems confusing, just pretend that it is in a car . . . that may help or may not.

Given what you described, I would do the following.

1) See if you can get that engine to turn using a good size socket wrench and a breaker bar on the crankshaft pulley.

2a) If the engine turns, then pull the spark plugs and see if the starter can turn the engine without having the plugs in.

2b) If the crankshaft pulley would not turn with a reasonable (but not excessive) amount of force, then remove the outdrive and try again.

3) If the engine will turn by hand but the starter will not turn it, even with the plugs out, it is tending to point to either the solenoid or the starter itself.

Try those things and see what you get and update the posts on this thread accordingly.

 

[stonyloam]

if it just clicks, I suspect that the starter solenoid is defective, most likely the contact that sends current to the starter motor is burnt. Grab your voltmeter and check the voltage on the battery wire connection on the starter, should be 12v. Then put the voltmeter lead on the heavy terminal that feeds voltage to the starter motor, should read 0v. Have someone hit the key, the voltage should jump up to 12v. If not, bad contact in the solenoid, if it does then your starter motor may be bad. That is the safe way to check it. If the engine is stuck, you should hear the starter clunk as the gear engages the flywheel ring gear, and the battery wire will start to heat up, as it draws heavy current.

 

[Scott Danforth]

first step, clean all the terminals. make sure they are shiny and clean enough that you can eat off them.

turn the motor over by hand if need be. unlike what Ted mentioned, dont turn the crank by the crank bolt. the bolt will break off. they make crank turning tools

you can turn it by pulling the plugs and grabbing the belts, or with the plugs out, turn the pulley (mounted to the hub of the balancer).

regarding your carb. I/O's dont get a primer bulb.

 

[kev301sam]

I bypassed the solenoid by using a jumper wire on the starter from Red to Yellow/Red stripe wire and got it to turn over. Bad solenoid I assume then?

 

[NHGuy]

Well now you are making progress. Try jumping the slave solenoid up on top of the engine. There's also a nice tutorial in the stickies on starter function.

 

[dubs283]

There's also a nice tutorial in the stickies on starter function.

Absolutley

Start there...Lots of good info in the Adults Only Section

 

[stonyloam]

If you went fron red (12v) to y/r (wire from slave) and it turned over, then it is not your starter solenoid, it is your slave solenoid that is giving you the problem. I think what you did was bypass the slave solenoid.