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Lookin good Mike. I bet it runs great now.
 

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Discussion Starter · #585 ·
Well heck!!!!! I hurt the motor in the 38 at the races last weekend. Started getting blow-by through the valve cover breathers. Checked for any ticking from valves, couldn't hear anything. I ran it a couple more times and called it a day. So I had time today to pull the plugs and do a pressure check. I had 175 to 180 lbs in all of the cylinders but #6. It only had 50 lbs. So ended my racing season pretty darn quick. I will photo the tear down if any of you guys are interested, or just post when I am done. Fun, fun, fun.
 

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Well heck!!!!! I hurt the motor in the 38 at the races last weekend. Started getting blow-by through the valve cover breathers. Checked for any ticking from valves, couldn't hear anything. I ran it a couple more times and called it a day. So I had time today to pull the plugs and do a pressure check. I had 175 to 180 lbs in all of the cylinders but #6. It only had 50 lbs. So ended my racing season pretty darn quick. I will photo the tear down if any of you guys are interested, or just post when I am done. Fun, fun, fun.
boy that really is too bad. Sounds like broken rings or A broken piston. Hope it’s salvageable. Hope you get it straightened out Mike. And yes I would like to see what happened. Although not the favored pics to see from our hot rod buddies. Rather see the build up on creation. Wishing for the best.
 
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I was thinking the same as Mario, rings or more likely a problem with a piston especially with that much cylinder pressure loss. You didn't mention when you did the leak down test if you were able to hear the escaping air coming through the intake or breathers. Hopefully when you tear it down it'll be something relatively inexpensive to repair.
 

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Discussion Starter · #588 ·
I did a compression test initially to check the health on the pistons and cylinders. I borrowed a leak down tester today so will do that reading tomorrow. Keeping the crying towel handy.
 

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That's too bad Mike. I sure hope it's just a set of rings, and not anything worse.
Back in the late 60's I had a '57 Chevy with 283 and not long after completely rebuilding it the engine started running on 7 cylinders and blowing smoke out the tailpipe. Tore into it and found a tiny hole in one piston that was barely visible on top, but had a .5"-.75" crater on the back side. Looked like glass that gets hit by a rock the way it blew out.
 

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Discussion Starter · #592 ·
Spent most of the day in the shop yesterday. Got everything almost ready for the engine to come out. Pulled the intake and found the valley pan and expanded upwards (see photo). I am not totally sure how that happened, any ideas? Checked the #6 cylinder and it shows some scuffing, but nothing I can catch a nail on. Thinking I might get away with a hone job and new bearings. I will know more when it is out and I pull the piston.
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Had to be some substantial crankcase pressure but if the pistons look good and no broken rings found I’m not sure what did that. What compression do you run in that block Mike? I guess number 6 is the low compression cylinder? Were the rings broken?
 

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I'm guessing that since you didn't mention anything about hearing the air escaping through the carbs, possible intake valve problem, air escaping through the headers, possible exhaust valve problem or escaping through the valve cover breathers, possible rings or piston issue during the leak down test it wasn't that evident. How fast was the cylinder bleeding down? Looking at the photo of the piston and there not being any signs of detonation, valves hitting it or piston damage my guess would be a broken ring or rings.
 

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Discussion Starter · #596 ·
Hi, sorry I wasn't too specific on the leak down test. It was definitely coming from the valve covers. 100% leak down. Sounded like a faucet running. I should know for sure ( I hope) tomorrow.
 

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Thanks for the clarification on the leakdown results. If the cylinder was losing pressure that quick and it was really that noticeable from the valve covers, straight up from the crankcase it's almost got to be rings. I hope that's all it is and not something way more expensive to fix especially if I remember correctly and that's a fresh motor.
 

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Sounds like the extreme pressure escaping back into the crankcase likely pushed the valley cover up. A big backfire could also result in that happening too, but if you've never had that happen it's likely not the culprit.
Still hoping you've got a simple fix, and wont be too costly. Nothing broken is a good sign.
 

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Discussion Starter · #599 ·
Got the engine out and the oil pan off. Everything looks pretty uniform and oily clean. Took loose number six and slide it out, as soon as the ring lands hit air, parts started falling out of the cylinder. Piston lands are shot, all the rings broke. On the bright side, the bearings look good, connecting rods are good as well. No deep marks in the cylinder. So we will see. Now I have to find a machine shop. All the older guys are retiring or kicking off.
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Well Mike from a repair cost stand point that's got to be in good news column. From the "son of a bitch" stand point it's got to be in the "son of a bitch" column.
 
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