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Old 11-04-2003, 10:02 PM   #1
shuttermutt
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<gulp> I hadn't thought of that possibility!

Those of you that followed this thread are aware that my 68 is currently down waiting on parts. Anyway, I was talking to my old man this evening and we ran through the symptoms again. He reminded me of a rather nasty possibility... a hole in a piston!

I'm keeping my fingers crossed, but only a compression test will tell for sure. In the mean time, I'm hunting down an HEI unit and a swap-on carb to eliminate those possibilities. Oh, man... that'd be just my luck!

But, that wouldn't explain A) the fact that it threw a very similar fit about a month ago then cleared itself out and B) the off-idle hesitation, would it? That's more like what a pissy carb would do, yeah? Jeez... I hope so!
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Old 11-04-2003, 10:06 PM   #2
lukecp
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Didn't you say you have a cold knock?
It could be the problem....fairl unlikley. SBC's (especially 327's) are usually very tough motors...the piston shouldn't break unless the engine was revved overly high......

I think your problems will proably be solved by an HEI, good carb, and a tuneup
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Old 11-04-2003, 10:22 PM   #3
shuttermutt
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Cold knock (2-3 seconds on start-up), low power, poor gas mileage, low oil pressure at idle... it's all consistent, but (as far as I know) the engine hasn't been stressed that hard. I think I'm worrying too much. My wife laughs at me. While the truck is down, I'm "forced" to drive my BMW.
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Old 11-04-2003, 11:05 PM   #4
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I think you'd notice a lot of blow-by with a hole in the piston. You'd probably have smoke and oil coming out of the motor everywhere.
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Old 11-04-2003, 11:14 PM   #5
jamesi20
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Cold Knock,Lo Oil press.

I am concerned more than others about your problem!!! Low oil pressure and cold knock could very possibly be a Main Bearing problem.
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Old 11-04-2003, 11:38 PM   #6
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The knocking, and low oil pressure are either a main, or rod bearing, OR, maybe a cam bearing...the ticking and missing and backfiring thru carb, are flat cam lobe symptoms. I suggest pulling the valve covers, and looking for a very loose rocker arm.
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Old 11-04-2003, 11:42 PM   #7
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i AM INCLINED TO AGREE WITH cLASS OF 69..IT SOUNDS LIKE MORE THAN A CARB OR TUNE-UP PROBLEM.
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Old 11-04-2003, 11:48 PM   #8
shuttermutt
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Okay, maybe you guys don't understand the concept of making me feel better about this little problem!

What I want to hear is, "Oh, you forgot to change the <insert cheap part here>!" or "Ha! Just turn the <stupid little bolt> one-quarter of a turn!"

Oh, who am I kidding? I can see the writing on the wall and it spells R-E-B-U-I-L-D!
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Old 11-04-2003, 11:53 PM   #9
cableguy0
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actually you do not have to run a motor hard to put a hole in a piston running it lean will do the same thing. will burn a hole in a piston before you knew what happened
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Old 11-08-2003, 03:22 PM   #10
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Quote:
Originally posted by shuttermutt
Okay, maybe you guys don't understand the concept of making me feel better about this little problem!
We'll be here to help you feel better when it comes time to pick a new cam!! Can you spell LOPE ??
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