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Machine shop cracked my block

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Old Mar 4, 2024 | 02:57 AM
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Default Machine shop cracked my block

As I’ve chronicled on here, Last year I bought a project 1969 L89 coupe that needs everything done to it.
One of the first things I did was to source a casting date correct 512 427 block.
I eventually found a block from a guy in Wisconsin who deals in vintage blocks and engine building.
It was a very nice block, standard bore.
This fellow fluxed it, baked it and cleaned it. He then decked it.
He did NOT remove the galley oil plugs.
He shipped it out to me in California, and after a few months, My engine builder recommended a “master machinist” about an hour away from me to do the work on the block.
Well, 5 months go by, and still no word on the block machine work.

2 weeks ago I decided to just drop by unannounced to check on things.
The owner saw me pull into the shop and walked out to greet me (I don’t think he remembered me) and I asked him how things were going.
I explained who I was and his eyes got big and he immediately said that there was an issue with the block and takes me in to look at it.
They cracked the block in 3 places trying to remove 2 plugs in the rear of the block by the cam hole.



He said he thought his welder could fix it.
I said don’t do anything till I process this whole mess.
The crazy thing is no heat or penetrate oil appeared to be used. Just brute force.
When the brute force didn’t work, the guy just drilled out the plug and used an easy out with even more force.

I got many different opinions on how to repair it ranging from JB Weld, grinding the boss down to eliminate the crack, welding with nickel rod, brazing, etc

A buddy of mine who is friends with several vintage restorers all said the place to go was Lock and Stitch.
I looked this place up, made a call and emailed pics and spoke to a fellow that said it should be no problem.
The owner of LNS has over 20 patents on cast iron repair utilizing a unique heatless technique.
In addition to the heatless technique, they have the ability to braze it or weld it with a proprietary iron rod.
http://www.locknstitch.com/index.html
check out some of the repairs these guys have done. Pretty amazing stuff.
I received a tour of the place and when I tried to take pictures of the repair facility they asked me not to as some of what they do is proprietary.

After receiving the bad news, the following week I drove the hour to pick up my block and then drove another 4 hours to Turlock CA


After dropping off the block I turned around and drove another 5 hours home.
This repair will cost me between $1500-$2000.
The “Master Machinist” whose shop cracked it, blamed the guy in Wisconsin even though when he told me he had to remove the plugs, I asked if they could just stay in. He was adament about taking them out but said “not to worry they do it all the time” .Needless to say, I’m finding a new machinist.

Stay tuned, I should be getting the block back in 2-3 weeks and I’ll post up pics of the repair.

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Old Mar 4, 2024 | 04:54 AM
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Sounds extremely disappointing.
drill a hole at the end of the crack. Thus stop drilling the crack. Tap the hole with a pipe thread. Take brass rod. Thread the end with same pipe thread. Screw rod into tapped hole untill extremely tight. Drill a hole overlapping the threaded rod you just put in. Tap hole. Screw in brass rod. Continue to end of the crack. Repair the threaded hole in the oil gallery.
excellent repair. Cost you a couple feet of brass rod and your time.
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Old Mar 4, 2024 | 05:09 AM
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From an old restoration book I have.

It's an old British book. Thus the odd thread sizes. But you can get the idea. You can do this with simple hand tools and will not cost thousands.
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Old Mar 4, 2024 | 06:39 AM
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Love it when someone suggests a fix using JB Weld. Bubba is alive and well out there folks.
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Old Mar 4, 2024 | 06:58 AM
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Sounds to me that the "machinist" owes you for all or at least half of the repair
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Old Mar 4, 2024 | 07:08 AM
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I take it you paid big money for this block........because if not, I would hope you would just abandon it......
My piece of mind is another 512 block......is the date code that important without the original stamp?

Jebby
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Old Mar 4, 2024 | 08:11 AM
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$1500-$2000 for the stitch weld? On principle alone would I not pursue that. Sounds like they think they’ve got you over a barrel.

Although I don’t like welding cast iron, it’s a fairly common occurrence with blocks and where your damage is, shouldn’t be an issue.
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Old Mar 4, 2024 | 08:45 AM
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A British oil leak repair? Really? The Brits are famous for oil leaks. Good luck with your repair job.
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Old Mar 4, 2024 | 09:10 AM
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The shop that cracked it should pay to have it repaired at your place of choosing.If not I would've sued.
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Old Mar 4, 2024 | 10:31 AM
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Originally Posted by Jebbysan
I take it you paid big money for this block........because if not, I would hope you would just abandon it......
My piece of mind is another 512 block......is the date code that important without the original stamp?

Jebby
big enough money for me. I thought about just sourcing a new block, but decided to give the repair a go.
As far as the date code, at this point, not really.
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Old Mar 4, 2024 | 10:37 AM
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Originally Posted by 69L88
$1500-$2000 for the stitch weld? On principle alone would I not pursue that. Sounds like they think they’ve got you over a barrel.

Although I don’t like welding cast iron, it’s a fairly common occurrence with blocks and where your damage is, shouldn’t be an issue.
I had a local welder that is a car guy talk to me about repairing it by nickel rod welding.
I figured he might be $500 and I had no idea if that was the proper way to repair it.
Plus, I know you have to heat the block up to like 900 degrees to braze it.
The Lock and Stitch place definitely gave me the estimate based on what the engine is and the fact I drove 5 hours to deliver it.
I thought a repair like what I needed would cost around a $1000 and that is a lot in my opinion.
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Old Mar 4, 2024 | 10:53 AM
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that looks like a very stupid mistake by the "master"

i have used lock n stitch, yes its a very good process. however looking at those i would have probably opted for a cheaper weld repair. that is hidden in the bellhousing so not visible, could have not even dressed the weld left as much material as you wanted for strength.

honestly looking at those, you probably could thread some plugs in with some sealant and it would never leak.
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Old Mar 4, 2024 | 03:27 PM
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I can completely relate to your story. I had my original numbers matching block in my 82 done by a local shop and they completely destroyed my block beyond repair (spider web cracked the entire rear of block) by dropping it off one of the work tables going into a hot tank. To say the least I was pissed off would be an understatement. I demanded a new SBC block or a new Dart block since they were a Dart dealer as well. I go another 4bolter. They did some other sketchy stuff and NEVER went back. That was three motor builds ago. LOL Hope you can get things fixed or worked out.
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Old Mar 4, 2024 | 03:39 PM
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Used that lock and stitch method alot years ago on cracked heads.
Believe you can get a kit from Goodson that includes tap, reamer and cast iron plugs.
Drill, ream, tap. Insert plug, cut off, Peen. Repeat overlapping plugs.
For 1500-2000 for that repair SOMEONE is making good $$$$$.
Might save a few bucks doing it yourself.
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Old Mar 4, 2024 | 04:40 PM
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I don't know if you watch Graveyard Cars but they had a numbers matching block cast iron repaired.
Start at around the 10:00 minute mark. This block was toast, much worse that what you are dealing with but they fixed it.

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Old Mar 4, 2024 | 06:29 PM
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Damn, you could have drove to Norcal and pick up my 1969 512 for that.
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Old Mar 4, 2024 | 06:57 PM
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been told they arent freeze plugs, they are plugs for the sand casting process. And water doesnt expand while its freezing to push out plugs and then run out of the plugs. Water contracts as it freezes and the result is an expanding center .....freeze a plastic water bottle and you can watch it happen...freeze plugs are an old wives tale...misnamed

watched some casting videos...pretty impressive

Last edited by Rescue Rogers; Mar 4, 2024 at 07:10 PM.
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Old Mar 4, 2024 | 07:15 PM
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I know you wanted to throw up seeing that. Looks like they put the new guy on it, those should have been heated before even attempting. I had a similiar issue one time but was able to stop it before that happened. I was there when the machinist started to remove a cast iron plug out our a 67 435 intake. Couldnt budge it so he wanted to use a bigger breaker bar, I was nope and nope. Took it to a Machine shop and had them cut the plug out of it.
You are going to have oil pressure right there so this fix has to be good or you could lose the whole engine. I would go after the machine shop but you probably will get nothing from it. I'm still waiting for one to make a situation better from 15 years ago when they machines the numbers off a 63 block during rebuild.
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Old Mar 4, 2024 | 08:04 PM
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Originally Posted by ddawson
Damn, you could have drove to Norcal and pick up my 1969 512 for that.
Well, I may still need it!
PM me with what you have and the date just out of curiosity.
Thanks
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Old Mar 4, 2024 | 08:06 PM
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Originally Posted by J.Abbott
I know you wanted to throw up seeing that. Looks like they put the new guy on it, those should have been heated before even attempting. .
That's exactly what happened. New guy who's only job was to remove these plugs.
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