7.4L Mercruiser Won't Turn Over

[detanner]

My Mercruiser won't turn over. It's been sitting high and dry for three months. I did start it just before it sat up. I thought it was the battery. Typical symptoms for a low battery, clicking starter, so I added the house battery, and finally my truck battery. The clicking stopped and it just killed all the guages. I'm thinking something is frozen so I pulled all the plugs out and tried, nothing, almost like a dead short. I put it in gear and used the prop to roll the engine a little. Put it back into neutral and with all three batteries it turned over just a couple turns and stopped. I took the batteries to the auto store and had them checked...they are good. I'm going to check the starter tomorrow.

Any ideas on what this might be? Are the bearings or pistons frozen?

Thanks for any help.

Dave

 

[Haut Medoc]

Re: 7.4L Mercruiser Won't Turn Over

Pull the plugs, put a wrench on the bolt on the crankshaft & see if the engine will spin.....
I'd check my electrical connections for corrosion first, though....​

 

[cbear34]

Re: 7.4L Mercruiser Won't Turn Over

Like Haut said, make sure all of your electrical connections are clean. After sitting for 3 months the connections could be crusty causing poor cranking. I would check that first before tearing in to the engine.

 

[Bondo]

Re: 7.4L Mercruiser Won't Turn Over

Ayuh,......

And don't forget the Ground path......

 

[larrybest]

Re: 7.4L Mercruiser Won't Turn Over

Did you ever reslove this? I have just made a similar post but mine will turn ever so slightly and stop. Battery is fine. Starter checked out great. Just won't crank over.

 

[cpubud]

Re: 7.4L Mercruiser Won't Turn Over

after 2 1/2 years I would hope so.

 

[ENSIGN]

Re: 7.4L Mercruiser Won't Turn Over

While you're having the starter checked squirt some oil in the cylinders and let it soak for awhile