8070 670I engine crankshaft

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   Pulled the 670i engine from my 8070 tractor. Took the crankshaft to a machine shop and they said all the journals were at minimum spec and the crankshaft should be reground. The shop manual says that after grinding the crankshaft needs to be shot peened in the journal radius areas and then polished. Does this shot peening need to be done? I cannot find anyone that still does it. The crankshaft is the one from West Germany.

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electroman Members Profile Send Private Message Find Members Posts Add to Buddy List Bronze Level Joined: 08 Feb 2018 Location: nova, oh Points: 44	Post Options Post Reply Quote electroman Report Post Thanks(0) Quote Reply Topic: 8070 670I engine crankshaft Posted: 19 May 2018 at 9:56am
	Pulled the 670i engine from my 8070 tractor. Took the crankshaft to a machine shop and they said all the journals were at minimum spec and the crankshaft should be reground. The shop manual says that after grinding the crankshaft needs to be shot peened in the journal radius areas and then polished. Does this shot peening need to be done? I cannot find anyone that still does it. The crankshaft is the one from West Germany.

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DMiller Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Access Joined: 14 Sep 2009 Location: Hermann, Mo Points: 33196	Post Options Post Reply Quote DMiller Report Post Thanks(0) Quote Reply Posted: 19 May 2018 at 12:11pm
	Shot peening relieves stresses, most likely done to remove previous work load stress from the journals to counterweights after so long running. Has to be something to it, so would shop around and find those that still will, ship the crank and have it done.

DrAllis Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Access Joined: 12 Sep 2009 Points: 21410	Post Options Post Reply Quote DrAllis Report Post Thanks(0) Quote Reply Posted: 19 May 2018 at 12:20pm
	Just because the Shop Manual says it is shot-peened, doesn't actually mean it is. They made crankshafts both ways.....shot-peened and not shot-peened. If it truly is shot-peened, each radius will look funny, like it has been sand blasted in an area 1/8"+ wide. If there's no sign of any change in the surface shine from the journal thru the radius, it isn't shot-peened. The shot peen effect makes the steel look cloudy or dull in a narrow band all around the radius. I don't like reground cranks in a 7080 or 8070, if they are expected to be used heavy all the time. I hope these guys know how to grind a heavy-duty diesel crankshaft and not screw up the radius profile. If all they normally do are automotive cranks, they probably don't know diesels. If the do Cummins, Cat and IH crankshafts, they might be capable.

electroman Members Profile Send Private Message Find Members Posts Add to Buddy List Bronze Level Joined: 08 Feb 2018 Location: nova, oh Points: 44	Post Options Post Reply Quote electroman Report Post Thanks(0) Quote Reply Posted: 19 May 2018 at 1:30pm
	It is shotpeened

DrAllis Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Access Joined: 12 Sep 2009 Points: 21410	Post Options Post Reply Quote DrAllis Report Post Thanks(1) Quote Reply Posted: 19 May 2018 at 3:19pm
	If you regrind it and not have it shot-peened, it will not be as strong as it would have been had it been shot-peened. I'd use it like that in a 7040/7045 but not an 8070. That's just me. You do what you want. There used to be a place 20 yrs ago around Chicago that did that process.

bigal121892 Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Joined: 05 Jan 2010 Location: Nebraska Points: 808	Post Options Post Reply Quote bigal121892 Report Post Thanks(0) Quote Reply Posted: 19 May 2018 at 3:44pm
	I would not grind the crank for a 7080, 8070, 7580, 4W220, etc. If it needs to be ground, replace it. It will never be cheaper to replace it then now.

electroman Members Profile Send Private Message Find Members Posts Add to Buddy List Bronze Level Joined: 08 Feb 2018 Location: nova, oh Points: 44	Post Options Post Reply Quote electroman Report Post Thanks(0) Quote Reply Posted: 19 May 2018 at 6:43pm
	Thanks for all the replies. Took the crank from the macine shop and had another one remeasure the journal od's. None were out of spec so that is the end of that machine shop for me. By the way i found the place that is referenced in the shop manual; it was bouvht by Curtis Wright and they have a shop in Twinsburg ohio. Will call monday to see if they still do crankshafts and the approx cost

Meanolallis Members Profile Send Private Message Find Members Posts Add to Buddy List Bronze Level Joined: 04 Sep 2013 Points: 132	Post Options Post Reply Quote Meanolallis Report Post Thanks(0) Quote Reply Posted: 07 Dec 2021 at 10:11pm
	Did you ever find a good shop that would shot peen the crank properly?

bigal121892 Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Joined: 05 Jan 2010 Location: Nebraska Points: 808	Post Options Post Reply Quote bigal121892 Report Post Thanks(0) Quote Reply Posted: 08 Dec 2021 at 3:37pm
	Question for Dr Allis, I think I read or heard it was possible with some machining on the block, to put a crank from an IH DT466 in to the Allis block, thereby getting more cubic inches out of the Allis. Or am I wrong on that thought?

DrAllis Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Access Joined: 12 Sep 2009 Points: 21410	Post Options Post Reply Quote DrAllis Report Post Thanks(0) Quote Reply Posted: 08 Dec 2021 at 5:33pm
	I know of one, in a pulling tractor, done by Mark Gettinger. He said he'd never do another one. By the time he got the main bearing bores opened up to accept the larger diameter IH crankshaft, the main cap bolts were exposed. But, the overall length and the 5.35" stroke did fit inside the AC 426 block. Thrust bearing is on the rear, which required more machine work too.

bigal121892 Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Joined: 05 Jan 2010 Location: Nebraska Points: 808	Post Options Post Reply Quote bigal121892 Report Post Thanks(0) Quote Reply Posted: 08 Dec 2021 at 6:18pm
	So, probably not a very practical solution for making the Allis engine more reliable.

DrAllis Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Access Joined: 12 Sep 2009 Points: 21410	Post Options Post Reply Quote DrAllis Report Post Thanks(1) Quote Reply Posted: 08 Dec 2021 at 6:36pm
	No. He had steel main caps with a girdle, so everything stayed put. A 426 engine that isn't overpowered from what it was originally rated at and faithful maintenance will last a pretty long life. Any FWA or 4WD engine never lasts as long as a 2WD, because the engine always works harder due to greater traction and overall weight. Those who take a 7080/8070/7580 to over 200 HP on the PTO are just asking for two things: shorter service life and shorter service life.