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Block crack repair?


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This is a picture of the engine block that was in Ratsun, one of my Datsun trucks.  This is the left side of the engine, looking at number one and two cylinder walls through the core plug hole.

This engine was not leaking coolant.  



This was the original L-16 engine that came in Ratsun.  Other than that, is is just a L-16 engine.  It might have value as the OEM, or "matching serial number" engine.


Anyone know of a cracked block repair method?



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Good to hear from you, DM.

The machine shop I took the block to noticed it, after the block was cleaned.  The shop used a florescent penetrating dye to confirm the crack,  (Zyglo process)

I do not know if the block was frozen.  I took possession of the truck in April of 2013.  When I got it, there was no coolant in it, and some of the core plugs were rusted through.

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Yup, last year my boss JB welded two Detroit DD15 blocks that blew the air compressor and rod went out so violently that it made a crack in the engine block, and yes the coolant was leaking out the block, and yes those two engines are still running today with no leaks.


JB weld it.

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A machine shop can definitely stitch plug that. If you can find another block easy id just do that as the stitching is usually billed by the hour and thats a fairly long one.


You could weld it..............


You could also just get them to plug the crack ends to keep it from growing, then jb weld ithe rest of it.


You could get a 90 year old dude thats good at fixing model t blocks to braze it..


I would try to get another block before doing any of the above.

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I'm for getting a different block but if you want to try to fix it and take the stress off the crack drill holes at the ends of the crack and fill the bottom of the block with a block filler used for race engines. Just fill 1/2" up pasted the crack.

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Taking all things into account, since it is a numbers matching block to a vehicle to actually own (and want to keep?), I'd bag it and store it. Put another motor in the truck and if, someday, you want to use the original engine, have it professionally repaired.


Values of these Datsuns don't yet call for perfection, but they are climbing. If that's something that concerns you, don't have a normal machine shop repair it. Send it off to one of those antique restoration specialists on the east coast. A hasty repair now will be difficult to cover up later.

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Lock and stich it is a really slick way to do that exact repair. I used the process on a Lincoln sa 200 engine driven welder I own it worked perfect. I did the repair 3 years ago I run the machine a lot and it has not leaked any coolant. My crack was 5" long in the water jacket. I have had hit or miss luck brazing and welding sometimes it works sometimes does not you have to make sure you get all the way to the end of the crack or it just starts again with the heat and cool cycles. To find the end of the crack use aviation dye usually a 2 can kit spray that enables you to see the end of the crack. If you are going to weld drill a small hole at the end of the crack at both ends and v the crack all the way to get good penetration the holes you drill will stop the crack from continuing. I used lock and stitch because I use my welder for work I didn't want a problem it's how I make money. The processes took me about 1.5 hours all you need is a drill having 2 makes it much faster. If your interested call them they are very helpful. I have no affiliation to the company it is a great product they fix container ships engines with this same process look on line. Hope this helps. I would post pictures of my fix but I'm a computer idiot.

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