BOTH heads cracked!!
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<img border="0" title="" alt="[Mad]" src="gr_images/icons/mad.gif" /> <img border="0" title="" alt="[Sad]" src="gr_sad.gif" /> DAMN!
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Allen,I may be able to help out a bit <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
I'll give you details in a PM on KYFbodies
<small>[ August 23, 2002, 11:38 AM: Message edited by: sweetTA ]</small>
I'll give you details in a PM on KYFbodies
<small>[ August 23, 2002, 11:38 AM: Message edited by: sweetTA ]</small>
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</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by JPR:
<strong>Thats a casting flaw, either sand or air caused a pocket beween those cylnders and de-shrouding them exposed the problem. I saw that problem here while porting a set of heads and caught it before they were installed.
Joe.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">While I'm not an LS1 Head expert, I run a testing lab for Aerospace and Automotive castings. Those are not cracks. They are either miss-fill, or weld voids.
You can tell if the casting has been welded by looking closely at the machined surface. The aluminum will be a slightly different color with a sharp transition, often with very small pockets (0.1mm) in the welded area. Take some 600 grit paper to it and look under a loupe.
A welded casting is inferior to a correct casting. It is weaker, and more prone to cracking due to thermal stresses imparted during the welding process. Many castings fail penetrant inspection or X-ray. Some non-critical application allow for welding. Some casting are rejected for "core-shift" where the inside and outside of the casting are misaligned. In critical applications, they scrap them. Usually they saw the casting in 1/2 or do something to keep it from accidently being used prior to melting it down.
If it is a casting that failed due to core-shift, penetrant or X-ray testing, DO NOT USE IT. Unless you know why the casting was rejected. The wall thicknesses could be too thin, there could be internal cracks, etc.
If I was going to buy a suspicous head, wheel, crankshaft, block, or any casting or forging, I'd shell out the money to have it MagnaFluxed, X'ray'd, or Penetrant inspected. Because a failure under load can be expensive and dangerous.
<strong>Thats a casting flaw, either sand or air caused a pocket beween those cylnders and de-shrouding them exposed the problem. I saw that problem here while porting a set of heads and caught it before they were installed.
Joe.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">While I'm not an LS1 Head expert, I run a testing lab for Aerospace and Automotive castings. Those are not cracks. They are either miss-fill, or weld voids.
You can tell if the casting has been welded by looking closely at the machined surface. The aluminum will be a slightly different color with a sharp transition, often with very small pockets (0.1mm) in the welded area. Take some 600 grit paper to it and look under a loupe.
A welded casting is inferior to a correct casting. It is weaker, and more prone to cracking due to thermal stresses imparted during the welding process. Many castings fail penetrant inspection or X-ray. Some non-critical application allow for welding. Some casting are rejected for "core-shift" where the inside and outside of the casting are misaligned. In critical applications, they scrap them. Usually they saw the casting in 1/2 or do something to keep it from accidently being used prior to melting it down.
If it is a casting that failed due to core-shift, penetrant or X-ray testing, DO NOT USE IT. Unless you know why the casting was rejected. The wall thicknesses could be too thin, there could be internal cracks, etc.
If I was going to buy a suspicous head, wheel, crankshaft, block, or any casting or forging, I'd shell out the money to have it MagnaFluxed, X'ray'd, or Penetrant inspected. Because a failure under load can be expensive and dangerous.
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I am replying too this post with out reading every thing, Chances are someone already pointed this out. but that's Not an a mistake done by any porter... that is a casting problem in the 6.0 head. It's like that from the factory. It's not in every head but in quite a few.. I have done about 12 sets of these heads. That area has the crack in it from the factory. it's not a welded!!! Usraly if the head is not deck alot you would never see it.. it's about .040 down into the casting wired but true.
Brent
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<small>[ August 23, 2002, 11:24 PM: Message edited by: One Monkey ]</small>
Brent
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Engines and Cylinder heads.
<small>[ August 23, 2002, 11:24 PM: Message edited by: One Monkey ]</small>
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Look at the bubbles in picture #3.
Are you going to tell me that ISN'T welded?
<small>[ August 23, 2002, 11:32 PM: Message edited by: McRat ]</small>
Are you going to tell me that ISN'T welded?
<small>[ August 23, 2002, 11:32 PM: Message edited by: McRat ]</small>
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6.0 heads dose not have a colant passage in between that area.. in fact that hole dose not go all the way too the other side it ends at nothing.. it's Identical in every head that has it. It's also very easy too fix!! usraly you know way before hand if it's going too be a problem. Chances are there are heads that get out with out anyone knowing it's a problem at that spot. I had a head done for one of My custumers car.. and I need too deck the head .080. at about .050 I was in too the pitt completely. I had it welded, then remachine. the car makes 502RWHP and 550RWTQ with 11.8:1 compression and have being running for over 10,000 miles with out any problems. While at SAM I came accross more casting like that.
So if you ask me just weld it it will be fine.
It was not welded It was like that from the factory I am sure of that.
the shop that did your heads should of seen the pitt when there deck your heads... If it was our shop I would of have it fixed before I sent the head out.. so you might want too just have them take care of it for you.
Brent
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So if you ask me just weld it it will be fine.
It was not welded It was like that from the factory I am sure of that.
the shop that did your heads should of seen the pitt when there deck your heads... If it was our shop I would of have it fixed before I sent the head out.. so you might want too just have them take care of it for you.
Brent
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</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by McRat:
<strong>Look at the bubbles in picture #3.
Are you going to tell me that ISN'T welded?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Nope not welds!!!
the first time I saw it thats what I figuer it was alos... but after seeing it in as many heads as I have it's a casting defect. trust me.
Brent
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Engines & cylinder heads
<strong>Look at the bubbles in picture #3.
Are you going to tell me that ISN'T welded?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Nope not welds!!!
the first time I saw it thats what I figuer it was alos... but after seeing it in as many heads as I have it's a casting defect. trust me.
Brent
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Those heads look like they have been welded to me also.
If I were you I might would pull my short-block down and put new bearings, etc. in. I have had some bad experiences with blown head gaskets(ruined the bearings and spun a couple of rods..... on a couple occasions)
Josh S.
If I were you I might would pull my short-block down and put new bearings, etc. in. I have had some bad experiences with blown head gaskets(ruined the bearings and spun a couple of rods..... on a couple occasions)
Josh S.
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OPPPSSS!!! My bad! I didn't wait for ALL the pictures to load!
Those heads were welded. No doubt at all. The last picture has the characteristic bubbles and you can see the line on the deck where the weld starts and ends.
<small>[ August 23, 2002, 12:21 PM: Message edited by: McRat ]</small>
Those heads were welded. No doubt at all. The last picture has the characteristic bubbles and you can see the line on the deck where the weld starts and ends.
<small>[ August 23, 2002, 12:21 PM: Message edited by: McRat ]</small>
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BTW, that is one of the WORSE places to weld a head at. That is an area that is highly stressed to begin with due to thermal differences and the pressed in valve seats.
Me personally, I'd be really pissed if the seller knew they were welded there and sold them anyways.
Me personally, I'd be really pissed if the seller knew they were welded there and sold them anyways.
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We'll see what happens next week. I'm dissappointed because I spent money on getting my heads worked and now I have to start off with a new set of heads all over. I really doubt if I'll be able to get my money back for the work done on them.
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The little pock marks are not uncommon to see after smoothing out the factory sand casting in the chambers.
Some of my 98 ls1 heads look like that after I smoothed the chambers.
You don't see it with raw casting surfaces.
So the pock marks do not automatically mean they were welded IMO.
Steve
Some of my 98 ls1 heads look like that after I smoothed the chambers.
You don't see it with raw casting surfaces.
So the pock marks do not automatically mean they were welded IMO.
Steve
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OK, if you don't think those are weld bubbles, take a look at pic #2. Look about .375" down from the deck void, and see the "witness mark" from the weld. It is a thin dark line.
I've seen 100's of welded cylinder heads. Probably thousands. I used to rebuild cylinder heads at SIR, a Volkswagen shop. Granted different heads, but still welded/cast aluminum.
And I've also inspected thousands of other castings. Welded, not welded, voids, cracks, core-shift, etc.
While I can't say for 100% sure without looking at the head under high magnification, those pictures depict what a welded head looks like. Even if there was no voids, I'd still say they are welded.
I'm not saying welded heads are all bad. But many are. I've seen many heads crack during the welding process. If you do weld aluminum heads, always store them in a hot oven before welding, and weld them while still hot to reduce the chance of cracking, then check them throughly after welding for cracks.
I've seen 100's of welded cylinder heads. Probably thousands. I used to rebuild cylinder heads at SIR, a Volkswagen shop. Granted different heads, but still welded/cast aluminum.
And I've also inspected thousands of other castings. Welded, not welded, voids, cracks, core-shift, etc.
While I can't say for 100% sure without looking at the head under high magnification, those pictures depict what a welded head looks like. Even if there was no voids, I'd still say they are welded.
I'm not saying welded heads are all bad. But many are. I've seen many heads crack during the welding process. If you do weld aluminum heads, always store them in a hot oven before welding, and weld them while still hot to reduce the chance of cracking, then check them throughly after welding for cracks.
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I am not saying there are not welded... if for some reason the factory welds the heads in the exact spot, on a bunch of casting... then hey there are welds... But I tell you that everyone is Identical. I have seen this for about a year, now. and still don't have a answer as for the reason and the cause. I am just pointing out that's a preported defect.
I could go take pictures of some casting sitting on the floors of probaly everyshop that has the exact makings..
Now if there are damage from the factory, (it will have too be a machine because of the similarities in the damage) and say Suan (Valve god) had them welded. by the same person who can't weld for ****. then maybe... however the heads that I have seen them on have being heads that have being run on production trucks. So there could not be outcast from the factory.
Later
Brent
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<small>[ August 24, 2002, 02:32 PM: Message edited by: One Monkey ]</small>
I could go take pictures of some casting sitting on the floors of probaly everyshop that has the exact makings..
Now if there are damage from the factory, (it will have too be a machine because of the similarities in the damage) and say Suan (Valve god) had them welded. by the same person who can't weld for ****. then maybe... however the heads that I have seen them on have being heads that have being run on production trucks. So there could not be outcast from the factory.
Later
Brent
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Engines & Cylinder heads
<small>[ August 24, 2002, 02:32 PM: Message edited by: One Monkey ]</small>