How Bad Is It?
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Pro
Joined: Oct 2003
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From: Houston, Texas
How Bad Is It?
About a month back, I decided to make a quick pass and get around a truck to enter the freeway, I heard a snap and then some knocking, so assumed that I had finally destroyed the engine because the car was turbocharged about a year and half ago, but never got around to having a stand alone system installed, even though I had an AEM box at home and was using a chip.
However, had the car towed and finally got the engine out with the help of the great articles here. I was expecting a broken rod or something, but instead found a cracked #1 cylinder and a piece of the head broken off on the left side, would this be the result of a cooling problem? I certainly will have to replace that cylinder and assuming that the broken part of the head can be removed also, and have the others looked at. As I noted, the pistons are all in place, so no broken rods, however, on the left side, the cylinders easily came off, is that normal? I do not want to rebore the engine, but would it make sense to check for spun bearings and change those, more importantly, does opening the case require machine work if no obvious damage or are there concerns about future performance? Plan to take the heads to a machine shop and get updatd. What can be done about the pistons and cylinders, assuing, if no other damage, they can be cleaned and reused.
Would appreciate some feedback on possible causes, could it relate to my turbocharging of the car? I do not think that Iwas driving fast and actually have been babying the car knowing that the tuning was questionable. If I can do the required work, will certainly go for some of those while you are in there fixes.
Here are some pics of the damage and condition of the pistons.
biggles
However, had the car towed and finally got the engine out with the help of the great articles here. I was expecting a broken rod or something, but instead found a cracked #1 cylinder and a piece of the head broken off on the left side, would this be the result of a cooling problem? I certainly will have to replace that cylinder and assuming that the broken part of the head can be removed also, and have the others looked at. As I noted, the pistons are all in place, so no broken rods, however, on the left side, the cylinders easily came off, is that normal? I do not want to rebore the engine, but would it make sense to check for spun bearings and change those, more importantly, does opening the case require machine work if no obvious damage or are there concerns about future performance? Plan to take the heads to a machine shop and get updatd. What can be done about the pistons and cylinders, assuing, if no other damage, they can be cleaned and reused.
Would appreciate some feedback on possible causes, could it relate to my turbocharging of the car? I do not think that Iwas driving fast and actually have been babying the car knowing that the tuning was questionable. If I can do the required work, will certainly go for some of those while you are in there fixes.
Here are some pics of the damage and condition of the pistons.
biggles
Thread Starter
Pro
Joined: Oct 2003
Posts: 516
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From: Houston, Texas
Running low boost, 6lbs, so did not mess with the compression and yes to intercooler. No knock devices installed, assuming that the AEM would have eventually provided the answer.
biggles
biggles
Three Wheelin'
Joined: Feb 2003
Posts: 1,782
Likes: 109
From: Cambridge/Boston, MA
That is the sign of *major* detonation! I, personally, wouldn't put it back together without all new p/c and reconditioning the rods and checking the crank journals if I saw a cracked cylinder. At the very least. If you cracked a cylinder then I'm sure that all of the pistons and the rod bearings have taken a beating. Not what you want to hear I'm sure!
I didn't hear any mention of injection/fueling changes for the turbo?
Edit- Thinking about this. A cylinder crack might more likely be heat related if the piston was still intact. Either way, this was not a happy motor.
I didn't hear any mention of injection/fueling changes for the turbo?
Edit- Thinking about this. A cylinder crack might more likely be heat related if the piston was still intact. Either way, this was not a happy motor.
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Joined: Jun 2001
Posts: 3,695
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From: Arizona
Don't know what I'm seeing there. Is there a worn groove along the crack? Or is that dye or marker? Almost looks like something was in a ring groove or pin bore that cut a groove that ultimately weakened the cyl.
Generally detonation would burn a piston crown and have burning at the top piston ring land, and overheating causes scored cyl walls and scuffed pistons. Can't tell from the pics.
I'd get a set of p&c you might hit up blackbyrd he had a few engines torn down that may only need a re-ring. No idea as to condition. As long as it has no internal cracks the head should be fine. I'd check the rods and re do the big end bearings no matter what.
Generally detonation would burn a piston crown and have burning at the top piston ring land, and overheating causes scored cyl walls and scuffed pistons. Can't tell from the pics.
I'd get a set of p&c you might hit up blackbyrd he had a few engines torn down that may only need a re-ring. No idea as to condition. As long as it has no internal cracks the head should be fine. I'd check the rods and re do the big end bearings no matter what.
Thread Starter
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Joined: Oct 2003
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From: Houston, Texas
Thanks guys, I intend to move slow and put it back right, so agree that checking out everything really makes sense. The pistons do not appeared to be damage but will get everything checked out professionally, repair what I can and replace what I cannot. Just wanted to see what I was up against. Guess, if the block is not damaged and its limited to the head, then I should be happy, however, I did not expect a cracked cylinder.
biggles
biggles
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Three Wheelin'
Joined: Nov 2005
Posts: 1,250
Likes: 44
From: Bahrain = somewhere in the Middle East
Any sound from the back I always hope it's just a belt snapping... Sorry to hear it's not that simple.
You're definitely in for some work there.
If you're interested, I have a used set of P&Cs for sale (I'll throw in some new rings). They are structurally sound but would be good with reconditioning. These are the later style cylinders, like you have. PM me for more details (I'll be in the US in mid May and would bring them along - so no need for international shipping).
Good luck with the rebuild.
You're definitely in for some work there.
If you're interested, I have a used set of P&Cs for sale (I'll throw in some new rings). They are structurally sound but would be good with reconditioning. These are the later style cylinders, like you have. PM me for more details (I'll be in the US in mid May and would bring them along - so no need for international shipping).
Good luck with the rebuild.
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Thread Starter
Pro
Joined: Oct 2003
Posts: 516
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From: Houston, Texas
Thanks. I did hear a sound, but no belts, that would have been better. However, as it is, guess it could have been worse, broken rod, damage block etc. Will let you know on the P/C once I have mine inspected, although I certainly need to replace #1.
biggles
biggles