Mercruiser starter.

[raglover]

I had the same issue on a replacement starter on my 58 35johnson. Different starter but same issue. It was in fact the drive gear dragging every now and then on the flywheel ring gear. In my case I had to shim it "down" so the drive gear sat lower under the flywheel when at the resting position.

Bet you will need to do the same on yours. I finally found the issue when I was watching the motor with the cover off and saw a few sparks from the clash.

A friend who works on vintage cars told me about shimming and that it was not that uncommon of a need on older motors with new staters. You can get shim sheet stock from McMaster and cut it with tin snips to make a shim between the top bracket of the Sartre and the motor body to push it away from the flywheel

Hope this helps good luck

[rickinfarmington]

Well, for anyone following my thread. Talked to an old time Merc mechanic/instructor. He said there is only one part number for the starter for the in line six. He also said my problem is common when the new gear driven starter is installed. There is a Mercury service bulletin that addresses the noise problem. He will be bringing me a copy of the service bulletin to our boat meet today. I will publish the solution after reading the bulletin.

[rickinfarmington]

The service bulletin has not been found and today I pulled the starter again and am trying to determine just what is going on. In discussing this problem with all the Mercruiser parts houses, they all confirm that there is only one starter part number for this engine. Have not yet found a way to search Merc service bulletins. I will be taking the two starters to a certified Mercruiser tech for him to look at.
I can’t believe I am the first to have run into this issue.
Bottom line is, there is if you call any Merc parts house and ask for a starter for the in line 6, they will send you the same starter I have. This is getting really frustrating.

[Mumbles]

There’s lots of videos on YouTube explaining how to shim a GM starter. Here’s one:

https://www.youtube.com/watch?v=3cYqrKmVECY

[wiscoboater]

Go over to Iboats.com and in the forums they have one for Mercruiser IO’s and stern drives. Many of the guys on there are current or former Mercruiser techs. They will get you dialed in. Some of the best Mercruiser talent in the country over there.

[rickinfarmington]

Posted a request for help on Iboats.com and waiting for replies. Thanks.

[rickinfarmington]

After studying the two starters side by side, I finally measured the pinion drive gear. The new starters gear is 3/16s of in inch larger than the old starter. This tells me that the pinion gear is being driven into the flywheel and placing a side load on the starter shaft, causing all the noise I am hearing. I will try shimming the new starter. Seems as though this should be covered in a Mercury service letter.

[billw]

3/16" is a lot. Is yours an OEM starter, ARCO or some Chinese thing? I have had okay luck with OEM and ARCO. Sierra is hit or miss.

Long live American manufacturing!

[rickinfarmington]

This is a high dollar Mercury part that Mercury still claims should work. I will let you know how the shims work out when I install them in the morning. Given the fact that the new starts does engage the flywheel and starts the engine, indicates to me, that the shimming will solve the problem.

[rickinfarmington]

OK folks, If anyone ever has to replace the starter on a 1977 Mercruiser in line 6 cylinder engine, and they buy the genuine Mercury replacement starter #50-806965A4, you simply must shim the new starter using two 1/16" shims. Or one 1/8th inch shim.

Now why couldn’t Mercury just have added that to their instructions that come with the starter?? FYI, replacing this starter as installed in a 1977 Wellcraft is pure misery. Only a small person can physically get in there to reach the bolts.

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