1964-1989 Mercruiser 120 Starter Removal

[photolimo]

Hey everyone, I have been lurking around the forum using some guides and reading up on a project boat I came into possession of. It is a 1968 Larson All American, the motor/outdrive is a 120 Mercruiser with a 1964-1989 Mercury 2.5L MC-1. The serial number plate was missing when I received it but all the parts indicate that it is in fact a 1967-1968. I have tried to decipher some of the numbers on the block without any luck so far.

I have been trying to see if the engine will crank. I placed some Marvel Mystery Oil in each cylinder and inspected each with a tiny video endoscope. They appear to be visually in decent shape. After letting the oil sit for a while I tried to crank the starter but it appears to be ceased. If I jump it directly (without the solenoid) it does not move at all. I am under the impression this should spin freely. It pulls a large amp draw doing this.

My next step is to remove the starter but I am unable to access the bolt under the starter closest to the engine block. I have tried every 9/16 wrench/socket I have. They do not allow enough clearance to get the bolt off. The bell housing is just too close to the bolt to get anything on. Maybe I am trying the wrong bolt or maybe the starter was installed wrong? Any advice would be appreciated. Thanks.

 

[Bt Doctur]

use a very thin wall socket drive on a socket with the extention when its removed flatten out the dust cover a bit

 

[kenny nunez]

Another thing that should help, just below the inboard starter bolt and you will see a smaller bolt that goes through the dust shield and the adapter housing, there is a nut on the other side and you will need a 1/2” socket and combination wrench to remove it. Then you will be able to get straight on the starter bolt. After you get the starter off try to turn the engine with a large screwdriver prying on the flywheel.

 

[kenny nunez]

After you get the starter off try to turn the engine with a pry bar against the flywheel teeth.

 

[photolimo]

Thanks for the tips, I was able to get off the bolt after grinding down the sides of an old socket. Unfortunately after the first turn it cracked. Now I will be troubleshooting the starter and tapping the broken bolt.