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Anatomy of a hydro locked engine

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Old 05-07-2018, 02:06 PM
  #16  
FredR
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Originally Posted by GregBBRD View Post
You must have gotten a different set of pictures than I did....
I suspect it is my rose tinted glasses that help me see the glass is half full and thus hopefully avoid heart attacks, strokes, aneurysms etc etc -

My point of view is that if I was offered a motor that was described as having experienced hydro-lock and having sat in its own witch pee for 10 years I would have expected little to nothing to be of use but those pics suggest there is reason to be optimistic that might not be the case. As to how well it cleans up remains to be seen - had the rods been bent I rather suspect Kevin would have spotted that and if the bores turn out to be corroded they can be bored out subject to the depth of corrosion - thus maybe a potential platform for a stroker or whatever even if that is not the intent.
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Old 05-07-2018, 02:11 PM
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If none of the cylinder towers are cracked and the top of the bores are not pitted, any block is worth saving for future strokering, definitely. They're not making any more blocks, at least not until Adam gets around to it. I'm just envisioning the grating noises those pistons will make as the crank is turned in order to get them out.
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Old 05-07-2018, 07:00 PM
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Originally Posted by Kevin in Atlanta View Post
Greg's advice on cleaning is to ultrasonically clean the pistons to remove any oil residue/carbon on the sides and then soda blast the tops.

As mentioned above the whole point of the 89 engine is harvest the heads for a stroker that Greg will build once the dust settles at his shop. So if the block is no good no big loss.

Kevin
Although you haven't showed the tops of the cylinders to see if they got eaten up by the coolant, certainly almost any internal cylinder damage will clean up with a 4mm overbore.

That's a country mile in "engine speak", right?
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Old 05-12-2018, 10:27 PM
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Tops of the cylinders:

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Old 05-13-2018, 12:24 AM
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Originally Posted by Kevin in Atlanta View Post
Tops of the cylinders:

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Old 05-13-2018, 10:07 AM
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Originally Posted by GregBBRD View Post
Although you haven't showed the tops of the cylinders to see if they got eaten up by the coolant, certainly almost any internal cylinder damage will clean up with a 4mm overbore.

That's a country mile in "engine speak", right?
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Is there really enough material in the cylinder walls to take a 4mm over bore or was that tongue in cheek?
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Old 05-13-2018, 04:00 PM
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Well the original plan was to use an 86 as the base with 89 heads. Greg confused me above with his response, too. I'll wait for him to chime in. I'll follow whatever advice he gives.
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Old 05-13-2018, 05:00 PM
  #23  
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Start at 100, take 2 mm off the left side, then 2 mm off the right side. = 104mm. 4 mm bore.
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Old 05-16-2018, 09:05 AM
  #24  
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It is a long time since my geometry class but I thought a circle only had one side so what you are suggesting would be a 108mm bore?

Clearly my question was not asking how to do it rather will the remaining material result in a reliable engine?
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Old 05-16-2018, 02:17 PM
  #25  
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Sorry, too few smilie faces in my snarky post.

Greg Brown has built many 104 mm bore motors. Mine only has 12,000 miles in 8 years, but that's because I'm usually in the garage working on something, not out risking my license with questionable judgment. I was at his shop a couple of weeks ago when a customer dropped off his 6.5L stroker for a 70,000 mile service. And I'll go out on a limb and guess that Jim Corenman has multiple 10s of thousands of miles on his 5.9 (104 mm bore, 85.9 stroke) in the past 2.5 years or so. So yes, they're reliable.

Here's the remaining cylinder tower material with a 104mm bore. This was a '91 block, the legend is that the '85-86 cylinder towers were even thicker and thus are even better candidates.

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Old 05-16-2018, 10:14 PM
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That is impressive. Thanks Rob.
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