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Re: Small crack in my 426 block, Should I worry?? [Re: 3ddart] #1157779 01/16/12 02:19 PM 01/16/12 02:19 PM
Joined: Dec 2003 Posts: 22,696 Bitopia J jcc If you can't dazzle em with diamonds..
jcc If you can't dazzle em with diamonds.. J Joined: Dec 2003 Posts: 22,696 Bitopia	How about just skipping the welding, shorten the boss to reach solid good metal, and use a spacer for same length of stud, Weld/repair at next rebuild? I know its shadetree, and this moparts Reality check, that half the population is smarter then 50% of the people and it's a constantly contested fact.

Re: Small crack in my 426 block, Should I worry?? [Re: jcc] #1157780 01/16/12 03:02 PM 01/16/12 03:02 PM
Joined: Mar 2006 Posts: 579 Wattsburg, Pa D Dr V OP mopar
Dr V OP mopar D Joined: Mar 2006 Posts: 579 Wattsburg, Pa	Quote: How about just skipping the welding, shorten the boss to reach solid good metal, and use a spacer for same length of stud, Weld/repair at next rebuild? I know its shadetree, and this moparts Thank you all for the input, I decided to do it the right way and weld it properly. Head is off, I will prepare everything tonight and the welder is coming to the house weds night. I will update with pics. Eric 69 1/2 A12 BEE 4 spd 1968 Charger 383 1970 Roadrunner 440+6 Survivor 2019 Redeye 2005 FORD GT Red/White 2017 Viper ACR Extreme Red/White 1979 Branco Red/Red 2018 Porsche GT3 Miami 1971 440+6 Cuda 4 speed V2 2020 Sebring Orange Vette 1979 Chevy Boogie Hippie Van

Re: Small crack in my 426 block, Should I worry?? [Re: Dr V] #1157781 01/16/12 05:03 PM 01/16/12 05:03 PM
Joined: Jan 2003 Posts: 42,714 Spokane Washington ScottSmith_Harms Mr Wizzard
ScottSmith_Harms Mr Wizzard Joined: Jan 2003 Posts: 42,714 Spokane Washington	Before you weld it with heat you might want to look into stitch welding that. It may be a tough area to stitch weld but anytime you can repair cast iron wiothout adding heat you will be ahead of the game. BTW, stitch welding works VERY VERY well! Stitch Welding

Re: Small crack in my 426 block, Should I worry?? [Re: ScottSmith_Harms] #1157782 01/16/12 05:21 PM 01/16/12 05:21 PM
Joined: Apr 2006 Posts: 3,675 Akron, Ohio U.S.A. roadhazard master
roadhazard master Joined: Apr 2006 Posts: 3,675 Akron, Ohio U.S.A.	I agree with jcc and others about it being repaired before It looks real thin on the area where it cracked and if you have it welded I'd build up this area a little bit more so you have some wall thickness. Also I'd check into that stud being crooked. Find out why it is or what's causing it to be crooked. Could possibly be a crooked spot face where your washer sits underneath and should be remachined to it's square and pulls on the stud straight. May help eleviate some future problems with it cracking again.

Re: Small crack in my 426 block, Should I worry?? [Re: roadhazard] #1157783 01/16/12 05:41 PM 01/16/12 05:41 PM
Joined: Mar 2006 Posts: 579 Wattsburg, Pa D Dr V OP mopar
Dr V OP mopar D Joined: Mar 2006 Posts: 579 Wattsburg, Pa	Quote: I agree with jcc and others about it being repaired before It looks real thin on the area where it cracked and if you have it welded I'd build up this area a little bit more so you have some wall thickness. Also I'd check into that stud being crooked. Find out why it is or what's causing it to be crooked. Could possibly be a crooked spot face where your washer sits underneath and should be remachined to it's square and pulls on the stud straight. May help eleviate some future problems with it cracking again. The stud is crooked, I noticed it last night after the head came out. Im sure it would have cracked for anyone, it just happened to be my turn. OH GREAT!! I will straighten it out, get the boss thickened up and will be brand new. 69 1/2 A12 BEE 4 spd 1968 Charger 383 1970 Roadrunner 440+6 Survivor 2019 Redeye 2005 FORD GT Red/White 2017 Viper ACR Extreme Red/White 1979 Branco Red/Red 2018 Porsche GT3 Miami 1971 440+6 Cuda 4 speed V2 2020 Sebring Orange Vette 1979 Chevy Boogie Hippie Van

Re: Small crack in my 426 block, Should I worry?? [Re: Dr V] #1157784 01/16/12 06:02 PM 01/16/12 06:02 PM
Joined: Jul 2010 Posts: 2,091 Delray beach, Florida P Performance Only top fuel
Performance Only top fuel P Joined: Jul 2010 Posts: 2,091 Delray beach, Florida	If your planning on welding this in the car, i'm of the opinion your making a terrible mistake. welding cast iron that is under stress/ load can cause many other problems if not done properly by preheating and proper cooling techniques afterward. even then there's no guarantee the repair will last. it may appear fine after its welded, but the forming of martinsite around the weld area will weakin it. machine shop owner and engine builder

Re: Small crack in my 426 block, Should I worry?? [Re: Performance Only] #1157785 01/16/12 11:38 PM 01/16/12 11:38 PM
Joined: Dec 2003 Posts: 22,696 Bitopia J jcc If you can't dazzle em with diamonds..
jcc If you can't dazzle em with diamonds.. J Joined: Dec 2003 Posts: 22,696 Bitopia	Quote: If your planning on welding this in the car, i'm of the opinion your making a terrible mistake. welding cast iron that is under stress/ load can cause many other problems if not done properly by preheating and proper cooling techniques afterward. even then there's no guarantee the repair will last. it may appear fine after its welded, but the forming of martinsite around the weld area will weakin it. He's right, and I would be leery of any "good" welder that would attempt it. Reality check, that half the population is smarter then 50% of the people and it's a constantly contested fact.

Re: Small crack in my 426 block, Should I worry?? [Re: jcc] #1157786 01/17/12 12:44 AM 01/17/12 12:44 AM
Joined: Dec 2008 Posts: 176 Rome, GA G GTXX member
GTXX member G Joined: Dec 2008 Posts: 176 Rome, GA	You are about to destroy a repairable engine. Take it out and take it to someone that knows how to do it right. Yeah, you probably don't want to spend the money now to do it right, but do it the way you are about to and you will eventually have nothing to work with.

Re: Small crack in my 426 block, Should I worry?? [Re: jcc] #1157787 01/17/12 01:04 PM 01/17/12 01:04 PM
Joined: Jan 2003 Posts: 17,846 S.E. Michigan ZIPPY I Live Here
ZIPPY I Live Here Joined: Jan 2003 Posts: 17,846 S.E. Michigan	Quote: Quote: If your planning on welding this in the car, i'm of the opinion your making a terrible mistake. welding cast iron that is under stress/ load can cause many other problems if not done properly by preheating and proper cooling techniques afterward. even then there's no guarantee the repair will last. it may appear fine after its welded, but the forming of martinsite around the weld area will weakin it. He's right, and I would be leery of any "good" welder that would attempt it. Though I've done at-home repairs with special wire and so on, and that's OK for small minor repairs in areas that aren't under much stress (I'm sure you could find a post I made here about it)....I wouldn't attempt it on that area. There are folks out there who can repair it and make it last...here is one: http://mpdweldinginc.com/ Rich H. Esse Quam Videri

Re: Small crack in my 426 block, Should I worry?? [Re: ZIPPY] #1157788 01/17/12 04:24 PM 01/17/12 04:24 PM
Joined: Jan 2003 Posts: 16,376 D dogdays I Live Here
dogdays I Live Here D Joined: Jan 2003 Posts: 16,376	Zippy is a factory guy, Perf Only is a pro engine builder, and I am a mechanical engineer. I agree with them. Welding cast iron is a real art and success is not guaranteed. NO WAY can it be done with the block in the car, with any reasonable expectation of success. cast iron is really special stuff and heating/cooling have to be rigorously controlled to avoid either the weld or the heat affected zone developing cracks. Plus, if the hole is drilled and tapped wrong, how is welding going to fix that? Also, welding will almost certainly tweak the block so that parts aren't square, cylindrical, etc. How about stop-drilling the crack, drill and tap deeper for a long Helicoil, and use a longer bolt/stud? then torque to minimum. R.

Re: Small crack in my 426 block, Should I worry?? [Re: dogdays] #1157789 01/17/12 04:36 PM 01/17/12 04:36 PM
Joined: Mar 2006 Posts: 579 Wattsburg, Pa D Dr V OP mopar
Dr V OP mopar D Joined: Mar 2006 Posts: 579 Wattsburg, Pa	Quote: Zippy is a factory guy, Perf Only is a pro engine builder, and I am a mechanical engineer. I agree with them. Welding cast iron is a real art and success is not guaranteed. NO WAY can it be done with the block in the car, with any reasonable expectation of success. cast iron is really special stuff and heating/cooling have to be rigorously controlled to avoid either the weld or the heat affected zone developing cracks. Plus, if the hole is drilled and tapped wrong, how is welding going to fix that? Also, welding will almost certainly tweak the block so that parts aren't square, cylindrical, etc. How about stop-drilling the crack, drill and tap deeper for a long Helicoil, and use a longer bolt/stud? then torque to minimum. R. Dog, we are going to look at everything tmrw. Im in no rush to fix it improperly. Im not sure how I would place a helicoil. The area that the crack is in insnt a threaded area. It is only a sleeve that the stud slides down into then a nut goes on the end. It is just a hollow cylinder that the head bolt sits into, or did I misunderstand what you meant?

Re: Small crack in my 426 block, Should I worry?? [Re: Dr V] #1157790 01/17/12 05:25 PM 01/17/12 05:25 PM
Joined: Jan 2003 Posts: 16,376 D dogdays I Live Here
dogdays I Live Here D Joined: Jan 2003 Posts: 16,376	No, I'm embarrassed. I had pictured the hole as being threaded and if I knew everything I'd have known that it is not. Now that I've visualized it properly I don't know how I missed it before! That changes my thinking quite a bit. If it is not threaded the first thing to do is to drill a crack stopper hole at the end of the crack. Welding doesn't look like such a bad plan now. Actually the part does look like it was repaired before and too much ground off the near side. You could probably just face (cut) off the cracked part if you were sure the crack didn't extend further up under the surface, but.... Because of this I believe welding will work and the thin side could be built up, then remachined to make it really OK. R. Last edited by dogdays; 01/17/12 05:37 PM.

Re: Small crack in my 426 block, Should I worry?? [Re: dogdays] #1157791 01/17/12 05:52 PM 01/17/12 05:52 PM
Joined: Mar 2006 Posts: 579 Wattsburg, Pa D Dr V OP mopar
Dr V OP mopar D Joined: Mar 2006 Posts: 579 Wattsburg, Pa	Quote: No, I'm embarrassed. I had pictured the hole as being threaded and if I knew everything I'd have known that it is not. Now that I've visualized it properly I don't know how I missed it before! That changes my thinking quite a bit. If it is not threaded the first thing to do is to drill a crack stopper hole at the end of the crack. Welding doesn't look like such a bad plan now. Actually the part does look like it was repaired before and too much ground off the near side. You could probably just face (cut) off the cracked part if you were sure the crack didn't extend further up under the surface, but.... Because of this I believe welding will work and the thin side could be built up, then remachined to make it really OK. R. Great, I know exactly what you mean. Thanks to all the participants on this thread!! 69 1/2 A12 BEE 4 spd 1968 Charger 383 1970 Roadrunner 440+6 Survivor 2019 Redeye 2005 FORD GT Red/White 2017 Viper ACR Extreme Red/White 1979 Branco Red/Red 2018 Porsche GT3 Miami 1971 440+6 Cuda 4 speed V2 2020 Sebring Orange Vette 1979 Chevy Boogie Hippie Van

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