Hole drilled in my cylinder wall?

smokin247

smokin247

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I just popped my rear freeze plug out with a punch to install a block off plate. Well I found there is a 1/8 wide by 1/16" deep hole in the back of the cylinder wall. Looks like someone drilled the freeze plug out and went into the outer cylinder. How thick are the cylinder walls from the inside to the water jacket? This is a brand new engine I'm about to install it tomorrow. Am I looking at a serious problem?
 
Ouch. What model engine? Are you sure it's drilled?
Wall thickness can be all over the place to be honest. It can be tested by most machine shops. How long have you been running that block?
 
Yeah it looks drilled. The block is new to me. I had it decked and bored .020 over. Just finished building it up and can finally put it in now. Until I found this. I'm working on getting a photo to upload.
 
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How did you get the 1/16" depth figure? I doubt you're close to accurate. From my experience with pipeline corrosion, a pit can look much worse than it will actually measure out. I would UT the wall and get an accurate depth to figure the remaining wall percentage.

If it's not that deep, say 50% wall loss or less, I would run it if it were just a street to mild build.
 
"UT the wall"? And I can't afford to take this engine back apart and reassemble it. I used a straight edge and a punch. I wasnt going for an exact measurement. I can measure it more accurately when I get home.
 
Ultrasonic Test. Shouldn't have to disassemble to check it. The sensor we use is about half the size of a thimble. Not sure about what engine shops use, but I imagine it's similar.

You'd be surprised how deep a small localized pit has to be before it affects the max operating pressure.
 
you had the block decked and bored...they didn't hot tank it? if they did what kinda halfassed shop left the freeze plugs in..if they didn't hot tank it wtf kinda halfassed shop did the machine work..thats f'd up dude.
man id be more than pissed...not sayin it couldn't have got missed but thefreeze plugs should've been replaced long before the rest of the mtr got built
 
dieselbeef said:
you had the block decked and bored...they didn't hot tank it? if they did what kinda halfassed shop left the freeze plugs in..if they didn't hot tank it wtf kinda halfassed shop did the machine work..thats f'd up dude.
man id be more than pissed...not sayin it couldn't have got missed but thefreeze plugs should've been replaced long before the rest of the mtr got built
Click to expand...

Exactly my thought, unless.... They are the ones that did the damage and put in new frost plugs to hide it. We're these the original or new plugs you just popped out after getting the engine back?
 
I'll have to call some local shops to see what they have. The UT test would be able to measure from the outside where the hole is, correct? Yesterday my mind immediately jumped to thinking a sensor would be needed on both sides of the cylinder wall.
 
Using the equipment I have, I would reach in the freeze plug area and measure wall thickness at 12,3,6,9 o'clock of the spot. Average the 4 readings to get wall thickness. Measure pit depth. Subtract pit depth from average wall thickness and then come up with the remaining wall thickness.

That's all probably above and beyond though. If it's not in the top part of the cylinder, it's probably of little consequence anyways.
 
dieselbeef said:
you had the block decked and bored...they didn't hot tank it? if they did what kinda halfassed shop left the freeze plugs in..if they didn't hot tank it wtf kinda halfassed shop did the machine work..thats f'd up dude.
man id be more than pissed...not sayin it couldn't have got missed but thefreeze plugs should've been replaced long before the rest of the mtr got built
Click to expand...
The machine shop is a whole story in itself. I went to a "well known" shop that specializes in high horsepower diesel builds 3 hours from me. I have plenty of shops local but I wanted it done right so I payed extra and drove farther. The first time I got the engine back the valves contacted the pistons when turning it by hand. And this is after I tried to have reliefs cut in my pistons but they talked me out of it saying it was a waste of time on this build. Then when I measured my valve depth it was anywhere from .032" to .041". (I paid for a "valve job"). So I brought the head back to them and had all the valves re cut to .060". Which they did do for free, while I waited.
I paid for it to be hot tanked but the freeze plug had corrosion built up on the back of it. I doubt they even changed them. I supplied all the parts, so they had new ones ready to go.
biggy238 said:
Am I the only one that would run it? You're in the same boat either way? Run it until it becomes a problem.

Sent from my Moto X using Tapatalk
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I'm running it for sure and if it blows out I'll be posting the pictures here. But I was just hoping for some opinions or good info either way.
 
yea..at least its a rd mark so it shouldn't make an risers or anything but that's still crap...that shop boned ya..post up..

who did it
 
TheBigNasty said:
Using the equipment I have, I would reach in the freeze plug area and measure wall thickness at 12,3,6,9 o'clock of the spot. Average the 4 readings to get wall thickness. Measure pit depth. Subtract pit depth from average wall thickness and then come up with the remaining wall thickness.

That's all probably above and beyond though. If it's not in the top part of the cylinder, it's probably of little consequence anyways.
Click to expand...

^^this^^
 
UCF Machine in Carlisle PA. They also lost parts, lost a ton of bolts, and charged me for parts that I supplied to them.
 
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