Busting alternator bracket bolts HELP !!!!

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AlaskaTours
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Busting alternator bracket bolts HELP !!!!

Post by AlaskaTours » Mon Aug 11, 2008 12:43 am

I have the 8.1 Levitator I have 60 hrs on it and all of a sudden it started snapping the top main bolt that holds the alternator bracket to the block I called Levitaor and they sent me a new bracket beacuse they said the first one was milled wrong and told me to remove the secoundary bracket also as it was causing stress. So we did and put the new one on and 10 min later I was dead in the water and in ALASKA that's a big deal.... :shock: . Anybody got a clue ? We thought maybe metal to metal but nothing is touching anywhere ,New boat ,New motor ,New mounts. Costing me a a ton of money as this is my main tour boat and our season is short. Do the bolts going thru the bracket need to have a shoulder on them ? lock washer or flat ? It has broken 8 times ,Thank god I have a trap to catch stuff like that before it goes thru the prop. The prop is set perfect though maybe it was off causing vibration all the pulleys on the front spin fine.


HELP PLEASE !!!!!!!!


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MYDIXIEWRECKED
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Re: Busting alternator bracket bolts HELP !!!!

Post by MYDIXIEWRECKED » Mon Aug 11, 2008 7:24 am

What grade hardness are the bolts. We use bowmalloy bolts here at my work and they are grade 12 with grade 8 bendability. Really a good bolt. maybe you just need to upgrade your bolt hardness. just a thought from a mechanic...
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airduds
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Re: Busting alternator bracket bolts HELP !!!!

Post by airduds » Mon Aug 11, 2008 9:05 am

Dixie I've never heard of bowmalloy. Where do I find them? I have a little issue with a starter bolt.
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Re: Busting alternator bracket bolts HELP !!!!

Post by INSHORE ASSASSIN CHARTERS » Mon Aug 11, 2008 11:33 am

I just had this problem on my caddy put a new aluminum custom bracket I believe a potter. Nice stuff but It snapped my top alt bracket bolt maybe because its long anyway its grade 8 So I fabbed a brcket to reinforce it I called around looking for a grade 12 only place I could find was CATAPILLAR. Where can I order grade 12 online? 3/8" X 6"
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Re: Busting alternator bracket bolts HELP !!!!

Post by MYDIXIEWRECKED » Mon Aug 11, 2008 12:55 pm

Here is my bowman Reps. # Gary Trappy 772-263-3575 Tell him chester from Florida power and light told you to call him. He may be able to help you with the local dealer in your area or ship to you.
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Re: Busting alternator bracket bolts HELP !!!!

Post by JSlick » Mon Aug 11, 2008 1:44 pm

I have seen this, several of the boats we fish out of have had the same problem. I'm not sure what is causing it but call Amercian Airboats, they know what it is. I have seen this on the Air Rangers and some Silver Dollar boats as well, it doesn't matter what grade, these guys keep breaking them as well.

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Re: Busting alternator bracket bolts HELP !!!!

Post by crowhater » Mon Aug 11, 2008 1:53 pm

INSHORE ASSASSIN CHARTERS wrote:I just had this problem on my caddy put a new aluminum custom bracket I believe a potter. Nice stuff but It snapped my top alt bracket bolt maybe because its long anyway its grade 8 So I fabbed a brcket to reinforce it I called around looking for a grade 12 only place I could find was CATAPILLAR. Where can I order grade 12 online? 3/8" X 6"

I have broken my Potter bracket at the top twice and I broke the long bolt at the bottom twice. The last time I drilled out the alt and the head for a bigger bolt and used a grade 8. Guess what it broke again. I have never had the factory hardware break on any direct drive boat. Potter is making me a new alt bracket out of stainless.

I have watched my alt while I am going and it is smooth as glass no vibrations at all, so I am all ears as to the phanton cause of this problem.
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Re: Busting alternator bracket bolts HELP !!!!

Post by nomad41 » Mon Aug 11, 2008 2:31 pm

You can also check with : http://www.boltdepot.com They will sell you one or ever how many you need.Prices are reasonable.
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Re: Busting alternator bracket bolts HELP !!!!

Post by Whitebear » Mon Aug 11, 2008 2:59 pm

Saw some of my old Buick Boats do this. I finally found that if I did the following they didn't break.

1. A shoulder bolt is ok as long as the shoulder does not bottom against the threads. Thats almost a guaranteed break.

2. Make certain the bolt is NOT bottoming out in the threads, again thats almost graranteed to break.

3. We used a star lock or an automotive bolt with a head skirt with little teats under it.

Once we got all this figured we just used regular grade 6 bolts. Hope this helps. It may not be your problem but its cheep and easy to check it.

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