water jacket cracks

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Dec 3, 2019 | 09:56 PM

Nelson 2

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water jacket cracks

I'll try and avoid restarting this thread from previous years.

I have a pre 1977 351m/400 engine that I was going to use on a project car. Not so sure now because of the water jacket crack issues. The question is how far do I have to go "into" this currently running engine that has 150,000 miles on it in order to see the cracks, or can I check it in a different way such as a pressure test before I start turning any wrenches. Thanks to all

Dec 3, 2019 | 10:44 PM

85e150

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Seems like early blocks from Michigan are a potential problem. Since the leaks look to be in the valley, a pressure test would find them but you'd have to pull the manifold to see. (afaik based on the pictures)

https://www.tmeyerinc.com/tech/351m-400-identification/

https://www.projectbronco.com/Techni...the_rumors.htm

Short answer, full tear down and magnaflux to be safe.

Dec 4, 2019 | 09:23 AM

Nelson 2

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Thanks, I was expecting that.

Dec 28, 2019 | 09:45 PM

Nelson 2

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Engine date code

I want to check the date code before I remove this project engine, 351M-400. I know the code is on the rear of the engine next to the sending unit. Because I have to remove 30 years of grease and use a mirror to see can someone point out if the code is on the passenger side or the driver side of the block. Thanks

Dec 29, 2019 | 12:36 PM

alloro

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Quote:

Originally Posted by Nelson 2

The question is how far do I have to go "into" this currently running engine that has 150,000 miles on it in order to see the cracks, or can I check it in a different way such as a pressure test before I start turning any wrenches.

The only true way to test it is to strip it down to the block and magnaflux it.