Farm Equipment - Tensile strength #70277489 rod bolt(ARP)426

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Tensile strength #70277489 rod bolt(ARP)426

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Topic: Tensile strength #70277489 rod bolt(ARP)426

Posted By: SteveM C/IL
Subject: Tensile strength #70277489 rod bolt(ARP)426
Date Posted: 25 Jan 2010 at 8:27pm

Anyone know the tensile strenght on the ARP rod bolts for the 426 AC engine.ARP claims no bolt of these dimensions in their catalog to give specs(probably true since it was likely special order run).TIA

Replies:

Posted By: SteveM C/IL
Date Posted: 26 Jan 2010 at 8:38am

bump

Posted By: SteveM C/IL
Date Posted: 26 Jan 2010 at 10:30pm

lot of readers,no answers.LOL

Posted By: Lonn
Date Posted: 27 Jan 2010 at 5:48am

Guess we're all stumped.

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Wink
I am a Russian Bot

Posted By: JoeO(CMO)
Date Posted: 27 Jan 2010 at 6:05am

You might try calling ARP, ask them about your specific situation.

Also, will this help?

http://www.racetep.com/arprodbolts.html

Posted By: smuggler
Date Posted: 27 Jan 2010 at 6:14am

well not that particular part number but other arp 7/16 rod bolts are 220,000 psi. So I would say they gotta be close to that

Posted By: injpumpEd
Date Posted: 27 Jan 2010 at 10:29am

I will look at the tech bulletin tonite that came with the agco/arp bolts. I was going to post the torque sequence also.

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210 "too hot to farm" puller, part of the "insane pumpkin posse". Owner of Guenther Heritage Diesel, specializing in fuel injection systems on heritage era tractors. stock rebuilds to all out pullers!

Posted By: SteveM C/IL
Date Posted: 27 Jan 2010 at 1:05pm

ARP says their longest 7/16NF rod bolt is 2".These are 2 1/4.Nothing in computer sys(20yrs back) about these bolts...would have to search archives.Maybe these were built near the end of AC and got lost in the shuffle with Deutz and layed in a wharehouse somewhere till someone said "What are these?",then after some investigating they were determined to be just what they are.I first learned of them in 2004 when Tbran posted about them on the Gleaner page.I thought they were "new" then but who really knows?Maybe the were newly found?!In the end it probably doesn't matter that much about the specs as I suspect they are the "best you can buy". 70277489 gets you 2) 70277487 bolts and 1)70277488 instruction sheet. 2 bolts and instruction sheet for about $23.Not a bad deal in my book.

Posted By: smuggler
Date Posted: 27 Jan 2010 at 3:36pm

probaly Max Simpson would know more if this is the best bolt you can buy. We use custom rods with 1/2 bolts. Are old rods had 7/16 bolts in them but were totaly custom built rod.

Posted By: Hurst
Date Posted: 27 Jan 2010 at 4:09pm

I know for the 301, that size bolts (it's a 3/8 by I think 2-1/4) is made by ARP, but it's a size that they are under contract to sell directly to some rod manufacturer, and therefore don't sell them directly to the public. It took a couple of calls to ARP before I finally got forwarded to someone who knew the answer. They looked it up and told me they made them but couldn't sell them, which is why the normal call center people's computers say they don't make anything of that size and it took someone closer to the factory side of things to get an answer.

Hurst

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1979 Allis Chalmers 7000
5800 Hours

Posted By: DMiller
Date Posted: 27 Jan 2010 at 4:20pm

Connecting rod cap bolts are specialized equipment, they are not shelf stock bolts. Having worked Cummins engines for over twenty five years that is one lesson I can remember from rebuild classes. These are generally a high chromium content heat annealed bolt designed to stretch to a predetermined length gaining tensile strength in the process. They are closer to a spring steel than a hardness factor bolt.