Bad Crack Between Cylinders?
Thread Starter
6th Gear
Joined: Sep 2012
Posts: 6
Likes: 0
Bad Crack Between Cylinders?
Hello all! Pretty sure I had a blown head gasket and what do ya know...
While getting everything ready for the replacement, I noticed a small crack between 4 and 6. More pics available here.
It doesn't really go down into the cylinder, but it definitely worries me. Is this anything to be concerned about?
While getting everything ready for the replacement, I noticed a small crack between 4 and 6. More pics available here.
It doesn't really go down into the cylinder, but it definitely worries me. Is this anything to be concerned about?
Le Mans Master
Joined: Dec 2007
Posts: 6,422
Likes: 591
From: McHenry Illinois
I don't know whether it's cracked into the water jacket but it's not going to hold a gasket there. One of the pics shows it cracked down into the cylinder. Put a straight edge across it and see how much it's eroded away or if the surface is still flat. I would start looking for a block.
Last edited by '75; Sep 30, 2012 at 05:43 PM.
Race Director
Joined: Jan 2000
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From: Corsicana, Tx
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Cheapest and easiest would be to buy a new shortblock from somewhere. Next choice is to find a std bore block and use all your old pieces after some machinework.
It can be repaired..but you'll need to completely tear it apart to do it. Unless it's a matching numbers deal you're trying to save...it's time to move on. look at it as a SOI...a Significant Opportunity for Improvement!
JIM
It can be repaired..but you'll need to completely tear it apart to do it. Unless it's a matching numbers deal you're trying to save...it's time to move on. look at it as a SOI...a Significant Opportunity for Improvement!
JIM
Thread Starter
6th Gear
Joined: Sep 2012
Posts: 6
Likes: 0
It runs at about 185F.
Not sure on what timing is at, will have to check.
No engine mods.
Cruise is about 3200RPM.
Drifting
Joined: Jul 2007
Posts: 1,889
Likes: 23
From: Kansas
Yes Sir; I just bought a 1977 with antifreeze in the oil, I'm pulling it an installing a Vortex 1997 which I bored out 30 new steel crank, roller cam & lifters, & hoping I can find someone to haul off the old engine the day I pull it. I don't know if the block is bad or not., but I'm not going to tear it down to find out either. Where are you at. Have a great one. Gene.
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Thread Starter
6th Gear
Joined: Sep 2012
Posts: 6
Likes: 0
Yes Sir; I just bought a 1977 with antifreeze in the oil, I'm pulling it an installing a Vortex 1997 which I bored out 30 new steel crank, roller cam & lifters, & hoping I can find someone to haul off the old engine the day I pull it. I don't know if the block is bad or not., but I'm not going to tear it down to find out either. Where are you at. Have a great one. Gene.
In Maryland
Drifting
Joined: Jun 2010
Posts: 1,781
Likes: 15
From: Oxford Ohio
By the time you have it welded, and sleeve the cylinders, you'll have way to much money in it for what you'll have.
I'd pick up a bare block someplace and build it. If you go that route, you'll get a couple doz. suggestions for your rebuild in short order.
If you want a reliable driver when you're done, and money is the issue, clean, bore and hone your replacement block, pick up some pistons and put it together. You'll be in one of those situations where "while I'm this far" so you may as well recon the rods, ballance the bottom end. recon the heads, upgrade the cam. The list just keeps on coming.
I'd pick up a bare block someplace and build it. If you go that route, you'll get a couple doz. suggestions for your rebuild in short order.
If you want a reliable driver when you're done, and money is the issue, clean, bore and hone your replacement block, pick up some pistons and put it together. You'll be in one of those situations where "while I'm this far" so you may as well recon the rods, ballance the bottom end. recon the heads, upgrade the cam. The list just keeps on coming.
Burning Brakes
Joined: Jan 2007
Posts: 1,057
Likes: 4
From: Concord Calif
Unless you have some rare highly desirable car here and need the correct numbers dump that block and build what you want, but do remember that your heads are going to have a problem in their deck surface also. So if you find an engine to use as is you need to repair the heads also.
Safety Car
Joined: Mar 2007
Posts: 3,652
Likes: 49
From: Bridgewater nj
I killed my 427 the same way
you can sleeve it with the thick heavy sleeves but it's expensive and it is no where's near the strength it was so its really not worth it unless it was a numbers matching block that's really worth something....IMHO
you can sleeve it with the thick heavy sleeves but it's expensive and it is no where's near the strength it was so its really not worth it unless it was a numbers matching block that's really worth something....IMHO
