Mercruiser 3.0 cranking over issue

[abrx7]

I have a 1993 Bayliner Capri with a 3.0 Mercruiser. Progressively it has been getting harder and harder to start. When you turn the key you can hear the starter engage but it never cranks over. The battery is new so I know its not that. Originally I thought it was the starter so I put a new one on. That lasted a year until the nose cone blew off. Now a 3rd new starter is on. We were still having the issue so I went ahead and put a new solenoid on thinking it was that. We're still having the issue. I am 99.99% sure it is not an electrical issue. I really think it is binding up.

The boat will crank over some times but you have to play with it and keep trying. I really don?t want to do that because I know it?s putting a huge strain on the starter and eventually, it will break. A guy at the marina told me that when you replace the starter you need to replace the 2 bolts holding the starter on. He said that those bolts align the starter to the fly wheel. Is it really that simple? I was thinking the flywheel was all marred up from the starter blowing.

I was going to pull the starter off and remove the plugs and crank over the motor by hand to examine the flywheel. But I wanted to see if there was something else I should look at before doing that.

Side note: When it does turn over she fires right up and runs great. Its simply just a starting problem

 

[searay3]

Re: Mercruiser 3.0 cranking over issue

Take a look at the spark plugs. If any look brand new shiny white, you are getting water in the cylinders..Starters don't just break apart like that. If it is hydro-locking, you could also do internal engine damage like bending rods...

 

[abrx7]

Re: Mercruiser 3.0 cranking over issue

Plugs look like a normal used plug. Not white and shiny.

 

[searay3]

Re: Mercruiser 3.0 cranking over issue

If there is no water getting in, remove the spark arrestor and see if any fuel is leaking down the throat of the carb while it's sitting. Other than either fuel or water leaking in, timing could make it hard to turn over, but that alone couldn't bust a starter...New starter bolts and check timing....someone else will have more ideas I'm sure...

 

[Don S]

Re: Mercruiser 3.0 cranking over issue

but that alone couldn't bust a starter

Oh yes it could. Especially if the starter has the wrong bolts, or they are loose and the starter is moving around. Is it the original starter? A replacement? Old bolts on new style starter? Is the bracket on the front of the starter to the block in place?

 

[abrx7]

Re: Mercruiser 3.0 cranking over issue

Thank you for your reply's. Im alomst 100% sure water or fuel is not getting in where and when its not supposed to. Also the timing is dead on spec. But that is exactly what it sounds like when you try and turn it over.

The starter has been replaced and the origional bolts were used. Also all of the bolts are nice and secure. Im cheap and decided to just go to Advanced and get a starter off an 1987 S10. I know your going to scold me for doing that but it fit and worked (up until now). The starter is about 2 years old. The motor has seen maybe 24 hours with that starter. Is it possible that the sollenoid in that starter is bad? I find it hard to believe I have to put a starter in this thing every other year. And again I know youre going to get on me for it not being a "marine grade starter" but damn!

 

[Colliemcc]

Re: Mercruiser 3.0 cranking over issue

I've had problems the exact same as yours. I kept having problems with my starters and blew a few heads off them turned out manufactured ones where not making good enough contact wit the fly wheel as I got a oem one and its starts bang on since touch wood

 

[jimbo_jwc]

Re: Mercruiser 3.0 cranking over issue

Spray starter gear with Dykem blueing compond before installing or paint w/permanent marker , all my old Chevy ,Olds starters came with shims for under bolts , check gear engagement when you pull , use jumper cables around starter solonoid to verify , clamp on amper meter to see if starter has proper power ,a couple hundred amps if something wrong with motor /cant compress liquid solid without stalling starter hp. check blueing to make sure you'r not loading in bottom of starter gear .