[C1] leaking head update!!
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Joined: Nov 2000
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From: Beverly Hills (Pine Ridge) Florida
What heads are those (casting number & year Vette)?
Do you have a reason why they both cracked (freezing or overheating)?
If freezing, I would check block for cracks as well.............
If overheating, check block flatness.
But I have never seen heads crack like that!
plasticman
Do you have a reason why they both cracked (freezing or overheating)?
If freezing, I would check block for cracks as well.............
If overheating, check block flatness.
But I have never seen heads crack like that!
plasticman
Last edited by Plasticman; Jun 25, 2017 at 09:33 PM.
Le Mans Master
Joined: Nov 2015
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From: Really Central IL Illinois
Clarify PLS. This is one head with cracks or two head with cracks in the same place.
I have never seen this in 50 years with Chevy heads. Guessing it froze.
Sorry about your misfortune.
I have never seen this in 50 years with Chevy heads. Guessing it froze.
Sorry about your misfortune.
Le Mans Master
Joined: Feb 2012
Posts: 5,410
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From: Glen Allen VA
I have a friend that has done nothing but build Chevy engines since 45 years. First thing he does on a SB head is filp it upside down and throw some filings on the middle two cyls, then the magnet. 30 seconds he says qualifies or disqualifies 99% of the heads. But they don't break here. This looks like a freeze or poor torque procedure.
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Joined: Feb 2014
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What heads are those (casting number & year Vette)?
Do you have a reason why they both cracked (freezing or overheating)?
If freezing, I would check block for cracks as well.............
If overheating, check block flatness.
But I have never seen heads crack like that!
plasticman
Do you have a reason why they both cracked (freezing or overheating)?
If freezing, I would check block for cracks as well.............
If overheating, check block flatness.
But I have never seen heads crack like that!
plasticman
They are 461's dated, 1 28 65. Only the driver side head cracked. It cracked in two places. To the right and left side of the center exhaust ports.
I've always suspected a crack in this head. Never water dripping from it,but I could always see dried water run marks in these areas.
I've had the Vette since 1988, purchased it when I lived in New Hampshire. I started a full frame off resto in 2004. In 2006 me moved to Arizona. Vette moved in boxes. LoL!!! About 3 years ago I started working on it again. Finally a couple of months ago I was at the point if started it up. Had several issued that I worked thru but then the head had a very small water leak that just got worse.
I'm figuring that maybe some years ago, before I owned the Vette maybe it got frozen, and when I pulled the heads and re installed them during the resto it opened the crack up.
Mark
Last edited by havasumark; Jun 28, 2017 at 02:02 PM.
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Only Driver side cracked. But it cracked in two places. To the right and left side of the center exhaust ports..
Yes, my guess is that it froze as well. I have detailed the history on my Vette in one of the other questions in this original post if you would like to know the details.
Thanks,
Mark
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Joined: Feb 2014
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I have a friend that has done nothing but build Chevy engines since 45 years. First thing he does on a SB head is filp it upside down and throw some filings on the middle two cyls, then the magnet. 30 seconds he says qualifies or disqualifies 99% of the heads. But they don't break here. This looks like a freeze or poor torque procedure.
If you would like to read full detail on the heads, I have explained it in one of the other forum member questions in this post.
Thanks,
Mark
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New Replacements for leaking head
Yesterday I received my replacement heads. They are 461X heads dated B 13 3. Now Getting ready to install them and get motor back together, and try again to have a successfully running engine.
My fingers are crossed.
Mark
My fingers are crossed.
Mark
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The LevelAir suspension was an option in both 58 and 59, thus, those engines had holes for mounting the compressor.
Also, back then, there were some BIG trucks which had heads with holes on the ends for mounting the air compressor for the air brakes.
Also, back then, there were some BIG trucks which had heads with holes on the ends for mounting the air compressor for the air brakes.
Safety Car
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That's definitely a freeze crack. It is possible to do a permanent repair to that. It's called stitching. You would buy the plug kit. Then install overlapping cast iron plugs. You could do it in the car with an angle drill but it would be a PIA
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only other thing I have seen is guys using a pry bar in the exhaust port to loosen the head and forgot a head bolt .....cracked it....
Strange....
Strange....