I can't believe they let it go out the door.
Cylinder wall pitting question
Thread Starter
Pro
Joined: Oct 2000
Posts: 522
Likes: 0
From: Northeast MA
Cylinder wall pitting question
Hello,
I recently purchase a short block 383 engine and while degreeing the cam I noticed the #5 cylinder wall has a few pits and two fairly large craters that didn't clean up when it was machined .030 over. I attached two pictures of the area.In the largest crater I was able to pick out rust particles with a small probe. I am concerned the crater depth is too close to the water jacket? I don't know how thick is the wall is in that area? Before I continue with assembly I would like to know if it is OK for me to continue. I am concerned it might have a coolant leak or that the rings will not seal in the piston. I am waiting a reply from the machine shop but I would like to be informed before hand.
Thanks in advance.
I recently purchase a short block 383 engine and while degreeing the cam I noticed the #5 cylinder wall has a few pits and two fairly large craters that didn't clean up when it was machined .030 over. I attached two pictures of the area.In the largest crater I was able to pick out rust particles with a small probe. I am concerned the crater depth is too close to the water jacket? I don't know how thick is the wall is in that area? Before I continue with assembly I would like to know if it is OK for me to continue. I am concerned it might have a coolant leak or that the rings will not seal in the piston. I am waiting a reply from the machine shop but I would like to be informed before hand.
Thanks in advance.
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
That block left a machine shop like that?
Take it back before you go any further. I think that block can be bored more, maybe enough to get those pits cleaned out, but either way it'll require new pistons, and if it can't be bored...a different block.
You can't have pits like that.
Take it back before you go any further. I think that block can be bored more, maybe enough to get those pits cleaned out, but either way it'll require new pistons, and if it can't be bored...a different block.
You can't have pits like that.
Le Mans Master
Joined: Jun 2004
Posts: 6,231
Likes: 65
From: Seattle WA
St. Jude Donor '14
I think we're all in consensus.
I don't think that's not going to clean up with a cut.
Since you bought it as an assembled shortblock, just hand it right back and get your $$$...don't let them "fix" it.
I don't think that's not going to clean up with a cut.
Since you bought it as an assembled shortblock, just hand it right back and get your $$$...don't let them "fix" it.
Terrorizing Orange Cones
Joined: Oct 2007
Posts: 2,572
Likes: 17
From: Northern CO
Thanks for the good close-up shots, the affected area is detailed well.
If I'm not mistaken, the freeze-plug side of the block is where most of the thrust load is imparted on the cylinder wall during the power stroke; might get away with it for a low rpm, bargain application but not if you paid real money for a hi-perf application.
I think any reputable machinist would back you up in identifying those pits are a 'no-go' for a high torque motor. How much time have you got left to correct this problem? I hope the individual who bored that block refunds your investment or otherwise, makes the situation right for the loss of $ and time. You'd think they would have caught the problem long before actually stuffing a slug in that hole.
Many of us would fail that machinists work and wonder what else (if anything) did he/they not perform correctly, in this instance? A shop and/or technicians reputation is on the line, if they believe that kind of work is acceptable.
Good luck and keep us posted.
If I'm not mistaken, the freeze-plug side of the block is where most of the thrust load is imparted on the cylinder wall during the power stroke; might get away with it for a low rpm, bargain application but not if you paid real money for a hi-perf application.
I think any reputable machinist would back you up in identifying those pits are a 'no-go' for a high torque motor. How much time have you got left to correct this problem? I hope the individual who bored that block refunds your investment or otherwise, makes the situation right for the loss of $ and time. You'd think they would have caught the problem long before actually stuffing a slug in that hole.
Many of us would fail that machinists work and wonder what else (if anything) did he/they not perform correctly, in this instance? A shop and/or technicians reputation is on the line, if they believe that kind of work is acceptable.
Good luck and keep us posted.
Drifting
Joined: Dec 2005
Posts: 1,360
Likes: 3
From: NORTHEAST
That mignt be OK for a bone stock engine but when you paying for a performance build it shouldn't come through like that.
If this was built by a performace shop they should have sonic tested the block before any work was done and there should be enough material if it was sonic tested???????
I have seen work done like this as there are a lot of jobber shops that don't build performance engines and don't line hone, don't torque plate hone, square and deck or even do balancing and call that a performance engine.
But in the end they didn't pay much for the job so they actually got what they paid for so its really hard to complain.
Keep us posted on the results
If this was built by a performace shop they should have sonic tested the block before any work was done and there should be enough material if it was sonic tested???????
I have seen work done like this as there are a lot of jobber shops that don't build performance engines and don't line hone, don't torque plate hone, square and deck or even do balancing and call that a performance engine.
But in the end they didn't pay much for the job so they actually got what they paid for so its really hard to complain.
Keep us posted on the results
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