Weird noise
12-15-2012, 11:16 PM
#41
Race Director
Thread Starter
After spending some time with the bore gauge, it is one cylinder that is the problem, and I'm not even sure how they managed to hone one like they did. I guess the operator went to lunch and left the hone in the hole. The #8 cylinder is .008" over size in the lower part. When I check bore size I only go in a couple inches normally so I missed this completely. All the other holes are fine. The problem now is what to do. In any case the machine shop will be eating parts and whatever labor it takes to make this right. The block is already 4.155" so I think I'll want a new block. It's good that this is a winter project, because it's gonna be all winter before it gets done!
The shop has done work for me before and I've never had an issue, but when this is resolved, I'll go have someone else cut my parts. I can't believe it even happened. Monday will not be a pleasant day for someone.
The shop has done work for me before and I've never had an issue, but when this is resolved, I'll go have someone else cut my parts. I can't believe it even happened. Monday will not be a pleasant day for someone.
12-16-2012, 10:08 AM
#44
Team Owner
Member Since: Oct 2004
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St. Jude Donor '05
That would certainly cause some piston slap but not the sound you describe. How close to the deck were they? Must have been rocking in the bore. Any contact with anyhting?
Still think that noise may have been something else although it would be nice if this solved it. . Oil pump housing Ok no cracks?
Still think that noise may have been something else although it would be nice if this solved it. . Oil pump housing Ok no cracks?
12-16-2012, 10:35 AM
#45
Race Director
Thread Starter
12-16-2012, 10:40 AM
#46
Race Director
Thread Starter
That would certainly cause some piston slap but not the sound you describe. How close to the deck were they? Must have been rocking in the bore. Any contact with anyhting?
Still think that noise may have been something else although it would be nice if this solved it. . Oil pump housing Ok no cracks?
Still think that noise may have been something else although it would be nice if this solved it. . Oil pump housing Ok no cracks?
Maybe my description of the sound differs from yours. My bad!
12-17-2012, 03:50 PM
#48
Race Director
Thread Starter
Nor did I. It didn't sound like piston slap, but a more tinney type noise. I probably could have run it, but who knows how long the piston/rings would have gone? It's soo much easier with the engine on a test stand than it would have been with it installed in the car. I'm too old to fight that fight anymore.
The shop has already agreed that if the cylinder is what I have said it is, they will buy a new block.
12-17-2012, 11:05 PM
#49
Le Mans Master
You probably would have cracked the piston skirt long before the rings wore out if it was slapping that hard. They only flex so many times before they break.
One piston slapping would be hard to diagnose. Normally when we hear piston slap it is all 8 slapping.
One piston slapping would be hard to diagnose. Normally when we hear piston slap it is all 8 slapping.
12-18-2012, 12:40 PM
#50
Race Director
Thread Starter
I heard they fired the guy who did the honing job, apparently it wasn't his first screw up. I had good success with this shop previously, but I'm pretty gun shy after this. New block is on the way to me now, and probably won't go back to this shop.