Notices
928 Forum 1978-1995
Sponsored by:
Sponsored by: 928 Specialists

Anatomy of a hydro locked engine

Thread Tools
 
Search this Thread
 
Old 05-07-2018, 02:06 PM
  #16  
FredR
Rennlist Member
 
FredR's Avatar
 
Join Date: Jun 2005
Location: Oman
Posts: 9,708
Received 667 Likes on 544 Posts
Default

Originally Posted by GregBBRD
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.
Old 05-07-2018, 02:11 PM
  #17  
Rob Edwards
Archive Gatekeeper
Rennlist Member
 
Rob Edwards's Avatar
 
Join Date: Sep 2002
Location: Irvine, CA
Posts: 17,318
Received 2,557 Likes on 1,236 Posts
Default

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.
Old 05-07-2018, 07:00 PM
  #18  
GregBBRD
Rennlist
Basic Site Sponsor
 
GregBBRD's Avatar
 
Join Date: Feb 2005
Location: Anaheim
Posts: 15,221
Received 2,458 Likes on 1,460 Posts
Default

Originally Posted by Kevin in Atlanta
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?
​​​​​
Old 05-12-2018, 10:27 PM
  #19  
Kevin in Atlanta
Rennlist Member
Thread Starter
 
Kevin in Atlanta's Avatar
 
Join Date: May 2002
Location: Roswell, GA
Posts: 7,981
Received 741 Likes on 449 Posts
Default

Tops of the cylinders:

Old 05-13-2018, 12:24 AM
  #20  
Ducman82
 
Ducman82's Avatar
 
Join Date: Nov 2009
Location: Marysville WA
Posts: 6,981
Received 18 Likes on 11 Posts
Default

Originally Posted by Kevin in Atlanta
Tops of the cylinders:

Old 05-13-2018, 10:07 AM
  #21  
kiwiokie
Racer
 
kiwiokie's Avatar
 
Join Date: Mar 2005
Location: Tulsa, Oklahoma
Posts: 320
Received 5 Likes on 5 Posts
Default

Originally Posted by GregBBRD
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?
​​​​​
Is there really enough material in the cylinder walls to take a 4mm over bore or was that tongue in cheek?
Old 05-13-2018, 04:00 PM
  #22  
Kevin in Atlanta
Rennlist Member
Thread Starter
 
Kevin in Atlanta's Avatar
 
Join Date: May 2002
Location: Roswell, GA
Posts: 7,981
Received 741 Likes on 449 Posts
Default

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.
Old 05-13-2018, 05:00 PM
  #23  
Rob Edwards
Archive Gatekeeper
Rennlist Member
 
Rob Edwards's Avatar
 
Join Date: Sep 2002
Location: Irvine, CA
Posts: 17,318
Received 2,557 Likes on 1,236 Posts
Default

Start at 100, take 2 mm off the left side, then 2 mm off the right side. = 104mm. 4 mm bore.
Old 05-16-2018, 09:05 AM
  #24  
kiwiokie
Racer
 
kiwiokie's Avatar
 
Join Date: Mar 2005
Location: Tulsa, Oklahoma
Posts: 320
Received 5 Likes on 5 Posts
Default

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?
Old 05-16-2018, 02:17 PM
  #25  
Rob Edwards
Archive Gatekeeper
Rennlist Member
 
Rob Edwards's Avatar
 
Join Date: Sep 2002
Location: Irvine, CA
Posts: 17,318
Received 2,557 Likes on 1,236 Posts
Default

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.

Old 05-16-2018, 10:14 PM
  #26  
kiwiokie
Racer
 
kiwiokie's Avatar
 
Join Date: Mar 2005
Location: Tulsa, Oklahoma
Posts: 320
Received 5 Likes on 5 Posts
Default

That is impressive. Thanks Rob.



Quick Reply: Anatomy of a hydro locked engine



All times are GMT -3. The time now is 07:55 PM.