Is this Block fixable???

[CTX1836]

The 8N I picked up ended up having a cracked block. This was
repaired long ago with solder. And as you can see there are two
lateral cracks as well as a vertical. Since there is no pressure on this
block would JB weld be the best option? It was built out quite a bit
with the solder and has obviously worked this long. Just need to
know wether to scrap it or fix it. Id like to fix it if possible.

 

[CTX1836]

(quoted from post at 11:31:08 07/03/21) The 8N I picked up ended up having a cracked block. This was
repaired long ago with solder. And as you can see there are two
lateral cracks as well as a vertical. Since there is no pressure on this
block would JB weld be the best option? It was built out quite a bit
with the solder and has obviously worked this long. Just need to
know wether to scrap it or fix it. Id like to fix it if possible.

 

[old]

Might be able to fix it but the 8N is so common I'd look for a good used block. I parted an 8N out because of a cracked block

 

[Stephen Newell]

My first choice would be to replace the block. If that isn't an option there is a procedure known as lock and stitch which should work. https://www.youtube.com/watch?v=Pq0wfU4ZaKk

 

[grizz02]

I would replace it , your not sure if there is unseen damage say to a cylinder

 

[Welding man]

Believe me I know, it would cost more to lock and stitch that block than it would to but 3 N blocks. Lock and stitch is very expensive.

 

[CTX1836]

Im tempted to try and fix it and see if it holds water. If it does well its not under pressure and will probably work.

 

[old]

The 8N I parted out with the crack block had been fixed but I was not going to pass it on to someone else know it could start leaking at any time. I still have that block

 

[boler76]

what I have had good results with a cracked block like that is,, I removed rad, blocked one rad hose and connected shop vac to the other, now with vacuum inside sprayed brake cleaner in crack to clean it and then warmed block with heat gun and put JB weld on and watched it disappear into crack, after it has entered stop vac and let it sit to dry. voila fixed???

 

[Stephen Newell]

I've heard that before but I think it's the only way to save that block. It's one of the reasons replacing the block would be my first choice.

 

[gable]

(quoted from post at 13:22:52 07/03/21) Might be able to fix it but the 8N is so common I'd look for a good used block. I parted an 8N out because of a cracked block

My uncle learned the hard way fixing the block. Definitely better to just replace it.

 

[560Dennis]

Drill holes at end of all the cracks to stop the progression. Grind a Vee along cracks 1/4 to 3/8 wide . Braze it up with oxy/acetylene torch .
If you weld with nickel stick preheat to 400 f and cool slow
Good as new

 

[560Dennis]

You could use lock and sitch also but Im not familiar with it .

 

[Welding man]

Appearently you havent bought any nickle welding rod, brazing rod, acetelene or oxygen lately.The materials alone to preheat,postheat, weld, braze or even attempt to repair that block would be over $150.00, plus grinding wheels etc. and at least 3 hours labor. 8N blocks are too plentiful for that attempt.

 

[SVcummins]

 

[GDaly]

Maybe try cast-iron stick welding rod. It's made just for cast you just have to pre heat the cast. I've used it on exhaust manifolds with great success.