Problem with starter grinding
 

My Dad just had a motor freshened up, because; It had a blown head gasket and I guess water was getting in the cylinders and the motor would not start. He had his started checked out before reinstalling the motor and it was good.
When he went to start the motor in the boat he got it to start a few times initially but then the starter began to grind and eventually got stuck on the flywheel. He installed a new high torque starter and it pretty much did the same thing. So he got a new marine mini starter. The motor started a few more times and he got everything set up. So he went out the next day and it was gringding again and not turning the motor over.
This is all info I am receiving from my Dad, I have not been involved physically. I am going to give him a hand Sunday and wanted to see if anyone had any experience with this problem.

My first thought was maybe the block has a hairline crack near the starter mount, from trying to start it last year with water in the cylinder. But it was starting initially
He says there are no worn teeth on flywheel?
Someone suggested his bolts may be bent?

Any thoughts or help is appreciated, Thanks.

You're going in the right direction... however cracking the starter bosses on the block would take something freak. It's always worth a look. My question lies more in whether or not the flywheel is true, and perhaps if it's even tight. Who put the bellhousing/flywheel on?

Loose flywheel or Maybe loose starter.
 

Since he's reporting three diff starters I doubt this will help, but, I had the same issue after a starter change...worked fine for 4 or 5 starts then ground. Initially my thought was flywheel but, I found both starter bolts loose. Tightened them down appropriately and no promblem since.

Are you sure there is no water getting in now?

I checked out the flywheel some teeth are a little chewed, maybe 16th or 32nd, but it doesnt seem like enough to cause this problem.

We spun the motor over by hand/crank bolt to check out all the teeth, the plugs were out and no water came out of plug holes. We found a good clean spot on the flywheel and I put the starter in. we tried to start it, it grinded and sheered the front bolt off clean, in the block. This is crazy. it was an old bolt but still...

now we go back and try the inline bolt high torque starter.

Any advice...

my,
You have been through too many starters, I dont think another one is going to fix the problem. Unless it is a very high compression engine, it should not need anything more than a stock starter. I think you have another problem. Is the ignition timing correct ? It almost sounds like it might be kicking back. Also, it does not take much wear on the ring gear teeth to keep the starter from working properly.

The only other thing is to check all of the starter wiring and especially the grounds going to the engine block. Take them loose and clean the connections with a wire brush. It does not take much corrosion on a starter cable to keep the starter from making its full power.

Bill Koustenis
Advanced Automotive Machine
Waldorf Md

Also check your starter bolts. I found some to be 1/4" longer then the factory and the starter would snug up but not tighten. Then it would twist after a few tries. Did you reuse exisitng bolts?

Nordic95

You can get new starter bolts at the chevy dealer. Check them and make sure they aren't bent and definitely torque them down correctly.

Kind of gee whiz but also make sure the plug wires are on the correct cylinders? We all make mistakes...

In your first post you said "So he got a new marine mini starter" If this is a mercruiser starter, it comes with its own l bolts and you must use them.

I read wear you changed out the head gasket, I had this same problem a few years ago on a 454 mag. Hydro locked the motor, broke starter bolt off 'in block' and knocked teeth off of ring gear. It turned out that UNDER the riser / manifold gasket was rusted out and let water into one cylinder. I would pull risers and check under gaskets....

Really surprised no one suggested shimming the starter to get better contact. Shim kits are cheap, and it works.

Misplacing an exsiting shim that was there is easy to do when tearing down an engine, I have seen it happen and it has happened to me.

Shim kits usually come with three thicknesses, I used the middle one and got lucky, hard to measure the gear lash with twins. Too mush shim and the engine will turn over slower and may hang the gear after the start, so take your time. I also suggest new GM bolts.

Bingo.
I dont know why the bolt broke on me the first time(old fatigue or whatever) with the regular starter. But one of the bolts he gave me for the high torque starter was tool long so the threads got tight to the block and didnt tighten the starter to the block on the inside. he had so many different starter bolts and starters from last year he was all confused and trying to rush things,

We got it fired up, now he needs to get it to idle right:angry-smiley-038: Those twin setups are a b!tch to work on. Its a 35 Fastech w/ Bulldogs btw.

No shim
No water
Timing and idle will be worked out tomorrow, hopfully.

Thanks to everyone for chiming in.

Oh yeah, the inside bolt has to be "modified" to fit between the Mercury T style oil pan and the block. Is there a company that makes a bolt for this reason?