cracked flathead

Cleaned the grease and dirt off my 8BA block and found this. The oil was clean and no sign of internal cracks. Is there a way to repair this with out wielding? Maybe JB or something like that? Hate to waste an other wise good flat motor. Any ideas would be greatly appreciated. Thanks Brad

 

JB is strong enough to fix a cracked block, but it starts to gets soft at 250-300*... Soft as in cured latex caulk. It will still hold strong, but if the crack extends into a pressurized water jacket, there's a chance it could fail.
As temps continue to climb up to it's max rated temp of 500*, it gets softer and softer untill it's like peanut ****er. At that point it begins to smoke.
I believe they sell a high-temp version of JB. I'd go with that instead.

 

The tapered threaded pin method would be the right way.

 

X2. That's the preferred way at our shop. A lot more permanent than JB.

 

I can't tell from the picture. Is that a crack or casting flaw? Did you say you can't see the the crack on the inside surface? I'd say verify that it is a crack. I've seen all sorts of dimples, ridges, and furrows in castings. I'm not saying it isn't a crack, but I just can't tell from the picture.

 

why not just solder it up with solder a small propane torch should be hot enough the block is strong enough as is just have to fill the crack

 

2x...

 

Can't tell if it's a casting flaw from the pic but mine had a casting flaw in the same place that looks pretty much the same. I thought it was a crack at first too.

 

Here is a closer shot of the spot ,hope this is better?

 

Don't look like a crack, but who can tell from such a ****py picture?
(get rid of the phone camera an use a real one)

 

Hit it with a flap disk and see if it is indeed a crack or just is a casting flaw.

Or use some crack check dye and a black light if you are **** about keeping the rough casting look.

 

Yup can`t lose anything by smoothing it down and haveing a closer look. Thanks guys for the input.

 

I use jb weld to repair metal and then bake it to cover with powdercoating, I know for a fact it stays happy and hard at 375 degrees. regular red and white tube JB, not the quick dry yellow tubes.

 

looks more like a casting flaw , id get it magnafluxed and verify its a crack , if it is drill a 1/8th hole at each end of it to stop its progress groove it out and braze it or weldit with 55 rod

 

Start by spraying the inside of that area with WD-40 or something and see if anything comes through. Not 100% definitive but a start.

 

hey us welders need to eat too ya know.

 

Just an update on the block. After cleaning it down to a smooth surface it appears to have been just a flaw in the casting. The whole block is quite roughly cast . So another flat head will live to see the streets again. Thanks for all the input and helpful advice from you guys.This is a 53 Merc. 1/2 ton PU and I am building it for my Grand daughter who will get it on her high school grade in 2012. I really want it flathead powered . Will go with T-5 trans Toyota 4x4 power steering and disc brakes.A dropped front Axel 4" . My 46 ford PU has mustang II and air and so on &so on but I am going old school on the M-100.

 

Good luck with your engine!