04-07-2023, 08:32 PM | #1 |
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8ba head bolts
Good evening,
I have a Walt Dupont built (sept 2011) 8ba with Offy 1069-400 heads and developed a weeping head bolt. These are the head bolts ("F" 1047), some are in rough condition. Can anyone tell me more about them? Where to find them or recommend a replacement that's not from my local hardware store. Thanks! Louie |
04-07-2023, 08:40 PM | #2 | |
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Re: 8ba head bolts
Quote:
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The only thing nice about being imperfect is the joy it brings to others.... "Silver rings, your butt! Them's washers!" "We shot our way out of that town for a dollar's worth of steel holes!" - from 'The Wild Bunch' - 1969 https://www.youtube.com/watch?v=7NReUd2_0u0 |
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04-07-2023, 08:52 PM | #3 |
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Re: 8ba head bolts
My suggestions are: Fred Wilner @ Southside Obsolete, Mac Van Pelt @ Van Pelt's Auto or Michael Driskell at Third Gen Automotive for starters.
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04-07-2023, 09:13 PM | #4 |
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Re: 8ba head bolts
I've got a bunch of them. How many are you looking for?
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04-07-2023, 09:24 PM | #5 |
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Re: 8ba head bolts
Make sure that if you use...........used bolts that you check for thread stretching. When finishing my 8BA several years ago, I was short several bolts so I contacted a engine rebuilder in the area looking for replacements.
He showed me the difference between good use-able head bolts and ones that had the treads stretched. Once you see the difference, it is pretty clear which ones to re-use and which ones to recycle to the metal bin. Sorry -- no pictures to show. |
04-07-2023, 09:42 PM | #6 |
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Re: 8ba head bolts
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"Superimposing just the first five or six threads (usually an unworn portion of any head bolt) will show you quickly what the pattern should look like. Superimposing ALL the threads will quickly reveal any stretched bolts. The bolts always stretch just above the last thread which enters the block bolt hole threads." |
04-08-2023, 04:00 AM | #7 |
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Re: 8ba head bolts
That's how I do it. Hold the bolts together so the threads interlock. If they don't fit together cleanly and you have to rock them to get a match from end to end one is stretched. Checking against a third one will show which ones are stretched. I showed it in a video.
Mart. |
04-08-2023, 07:33 AM | #8 | ||
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Re: 8ba head bolts
Quote:
So after pulling one, two, then all of them, I have decided to replace them all. Figured since I ended up going down the rabbit hole, I wanted to visually inspect the block, fresh gaskets, and now a full set of bolts for some peace of mind. Thank you kindly for your offer. Quote:
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04-08-2023, 08:17 AM | #9 |
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Re: 8ba head bolts
Considering the fact that the properly torqued bolts don't exceed 50 ft/lbs any grade #5/8 will work, I also want you to know that most bolts are made over seas, so the quality may be doubt full. You might want to dubble nut a bolt and see how much it takes to brake it, or when the strech comes in.
Gramps PS when filling a goverment contract, you must use everything made in America However yoou can be given a waver for some material. I work with a steel fabricating Co. that has trouble finding simple things as nuts & bolts as well as screws & nails tha must be replaced if not properly documented. G |
04-08-2023, 02:23 PM | #10 |
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Re: 8ba head bolts
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Just an example, BELOW! Coop |
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