Starter bolts snapping need help

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AlaskaTours
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Starter bolts snapping need help

Post by AlaskaTours » Tue Sep 08, 2009 7:19 pm

Well my season is over up here in Alaska and what a season it was. We just now think we found the problem with the starter bolt problems ,But need to see if anyone can help. I have the 8.1 levitator and I have have snapping starter bolts once a week .To busy to shut down for the summer so I got good with an easy out and cordless drill this summer :D 30 min changing out starter bolts and taping out broke bolts :shock: Any way after a closer look and hair pulling and stress levels going up. We gathered up all 10 broke grade 8 bolts and they are all broke at the same spot.( the bolts break one at a time about every 5 hours of running time)

This is what we found I might be wrong "LET ME KNOW PLEASE" The block at the starter has about a .25 inch shoulder non threaded before the threads start. and there is a 16th of an inch gap around the bolts there and we are thinking that just enough that the torque of start up is bending them and breaking them after a bunch of start ups. :?:

Do they make a starter bolt bushing to tap into the block to snug up the bolt :?: The bolt going through the starter is snug no giggle . If they do I can not find it anywhere

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Re: Starter bolts snapping need help

Post by Norris » Tue Sep 08, 2009 7:37 pm

The right starter bolts will have a Knurled portion to fit tight in the recessed hole, however alot of us run the wrong bolts
with no kurl and they work ok. so your problem is something else... have you checked the way the starter gear meshes with the flywheel, many
times you have to shim the starter to get it right, GM was kind of loosy goosy on this... I would suspect your starter is toooo tight to the flywheel. Most GM dealerships should know about and have the shims..

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Re: Starter bolts snapping need help

Post by Rich Andrews » Tue Sep 08, 2009 7:48 pm

a pic would be helpful
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Re: Starter bolts snapping need help

Post by AlaskaTours » Tue Sep 08, 2009 8:01 pm

The starter is fine the bolts that are snapping are from levitator and NAPA.

Rich what kind of photos do you want ? Broken bolts ?
Thanks

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Re: Starter bolts snapping need help

Post by Rich Andrews » Tue Sep 08, 2009 8:07 pm

sure broken bolts,your starter...i know first hand if you bottom out a bolt to the block, it has no way for the shock or vibration to escape. Also, you may feel like your getting it tight when in fact your just bottoming out the bolt. Maybe measure the depth compared to your bolt?
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Re: Starter bolts snapping need help

Post by Rich Andrews » Tue Sep 08, 2009 8:10 pm

maybe your bolt is freezing it's nuts off?? Your in Alaska right?
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Re: Starter bolts snapping need help

Post by MYDIXIEWRECKED » Tue Sep 08, 2009 8:19 pm

Is your timing to far advanced???? I know it will break the nose off of an aircraft starter.
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Re: Starter bolts snapping need help

Post by Wild Bill » Tue Sep 08, 2009 8:40 pm

Lightweight reduction starter or old style? I put a rear starter suport bracket on my old style. Had to build one because that's the bracket everybody throws away when they replace the starter. :lol:

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Re: Starter bolts snapping need help

Post by Big Mac » Tue Sep 08, 2009 10:35 pm

Lots of good advice on the knurl of the bolt.
NEVER use a standard bolt, even if grade 8
Very important that the knurl also locates the starter to the block

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Re: Starter bolts snapping need help

Post by rbjscott » Tue Sep 08, 2009 11:25 pm

Were the bolts knurled? Chevy says you should replace the bolts every time you remove them. they are alignment dowells as well as bolts. Use a torque wrench.
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Re: Starter bolts snapping need help

Post by airduds » Tue Sep 08, 2009 11:58 pm

I went through this on a crate motor 383. Tried the knurled, non-knurled, shorter, grade 8, etc. Switched to the mini-starter and haven't broken one since.

No idea why.
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Re: Starter bolts snapping need help

Post by AlaskaTours » Wed Sep 09, 2009 2:02 am

OK you guys got me there what does a knurled bolt look like ? Is that the stamped diamond band at the bottom of the threads :? I went back out tonight and the knurled part (If thats what it is ) does not even come out of the top of the starter only threads. And the bolts are not bottoming out still have a good 1 1/2 inches and no they are not freezing their nuts off .........YET!!!! :D

Wild Bill It had diamond backs feather lite starter ,I took it off and put a heavy duty Chevy starter. And before you ask They were breaking off on the feather lite starter also.And it did not come with back bracket from factory on the Levitator

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Re: Starter bolts snapping need help

Post by rbjscott » Wed Sep 09, 2009 7:14 am

They make several bolt lengths and and also metric sizes. Some are only 1/4 inch different in lenght. Yes the diamond pattern is the knurl. I keep the orginal bolts to match the lenght. Once again I try to buy OEM starter bolts and it takes a good parts person to help you.
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Re: Starter bolts snapping need help

Post by somedumbredneck » Wed Sep 09, 2009 9:03 am

I had a caddy boat one time and had the same problem,, finnaly i got some real good grade 8 studs and done away with the bolts,, just loctite the studs and used nyloc nuts and never had this happen agine. if you have room to get the starter on with suds try it, i may work for you as well.. i would cring every time i hit the starter befor i fixed it.
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Re: Starter bolts snapping need help

Post by MYDIXIEWRECKED » Wed Sep 09, 2009 12:45 pm

ARP makes starter bolts...I'd try them if all else fails. They are the known, bada$$ bolt manufacturer. :D
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Re: Starter bolts snapping need help

Post by Wild Bill » Wed Sep 09, 2009 9:33 pm

The starter on my 489 BBC is the long old style, My block is also a MkIV so I don't know if they put the bolt boss on your engine or not but I have a little over 40 hours on mine so far. Just grade 8 bolts with flat and lock washers and I probably put a dab of blue loctite on. I think the bracket was built out of 1/8" or 3/16 X 1" angle and nothing broke yet. That's a lot of weight hanging off those bolts with the added propeller and other vibration.

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Re: Starter bolts snapping need help

Post by AlaskaTours » Thu Sep 10, 2009 1:25 am

Thanks Wild Bill will have to get on of those and give it a try.

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Re: Starter bolts snapping need help

Post by CactusJack » Thu Sep 10, 2009 6:21 am

I just spent nearly an hour looking for a knurled bolt to photograph to show you... :lol: I saw one just the other day while packing up to move.... no idea where it is now :lol: As usual, i was looking for a plain bolt and all I could find was the knurled one :lol: :roll:
I would reccommend you take airduds advice and get a little geared starter (less weight as well as smaller) It would suck having to repair the boat all the time during the season :twisted: I feel your pain :wink: WB's advice is also spot on, the big starters really need that front bracket to support thier weight (y'know, the bracket we all leave off) :lol:

If I spot the bolt again I will take a pic & post it.
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Re: Starter bolts snapping need help

Post by AlaskaTours » Thu Sep 10, 2009 10:50 am

Where can I get me one of them there stater brackets :D All I could find was some for a small block chevy. Trying to button it all up and test drive before the ice starts moving down river

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Re: Starter bolts snapping need help

Post by rbjscott » Thu Sep 10, 2009 11:28 am

The brace or bracket is a Chevy part, they were often on older BB chevys. If you can post a pictue of broken bolts showing the fracture surface or e-mail them to me. Another thing to look for if flex-plate run out.
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Re: Starter bolts snapping need help

Post by CactusJack » Thu Sep 10, 2009 1:47 pm

Alaska, if you have auto wreckers or auto electricians near by, check them, they prolly have mountains of old starters you can rat brackets off. You can prolly buy a dead starter (or just the field casing) with a bracket on it for a few bucks :mrgreen: They arent hard to make either, if you can weld :lol:

Although, you have to be quick to beat the scrap merchants these days... here anyway :wink:
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Re: Starter bolts snapping need help

Post by wildcard » Thu Sep 10, 2009 1:54 pm

you can build one with 1inch angle quicker than trying to find one,just measure and cut&drill

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Re: Starter bolts snapping need help

Post by grant » Thu Sep 10, 2009 2:01 pm

wildcard wrote:you can build one with 1inch angle quicker than trying to find one,just measure and cut&drill
I was beginning to think no one was going to say the obvious :shock: :shock: :shock:
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Re: Starter bolts snapping need help

Post by walleye52753 » Thu Sep 10, 2009 11:43 pm

I tried running standard bolts on a mini starter years back in the pits at the track! It ground away at my ring gear, bound up my starter, and left me stranded in a demo derby feature! I would definitely try an auto electric shop...(alternators,starters,etc.) They tend to know and carry options for these issues. atleast i have had good experiences with our local shops. Autozone and oreilleys carry a bolt kit for chevys but i am not sure that it is the same kit as your levitator package. good luck.

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Re: Starter bolts snapping need help

Post by rbjscott » Fri Sep 11, 2009 6:01 pm

Start bolt P/N 12338064. Torque is 35 foot-lbs. This is Chevy information.
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