Evaluate these cracks!!

4tfred

Junior Member
Have a block marked C8BA, so I assume "C" indicates that it is a Canadian vintage. It has sleeves and hard seats. The only cracks are similar to those in the images--no others visible around the valve seats

or C8ba-2.jpg

C8ba-03.jpg

C8ba-04.jpg cylinders.

So, what about these three I have shown. Fix or no fix?

If fixable, is it a job for an average do-it-yourselfer or machine shop?

Thanks!!!!!
 
I am not sure you have to do anything-sealer on the treads of the stud is all you need. Hopefully Walt or Ol'Ron will chime in with the definitive answer.
 
If you look in a ford service manual those cracks have part numbers, and require no attention.

R
 
The first two cracks you can pretty much ignore, they are captured and won't cause any trouble. The third crack can grow down into the center exhaust port and then you do have a problem.
 
You may want to use studs in those areas with permatex sealer on the threads when you put it back together & then run sodium silicate(water glass) in the cooling system
 
You may want to use studs in those areas with permatex sealer on the threads when you put it back together & then run sodium silicate(water glass) in the cooling system

That top bolt hole with the crack goes right into the exh passage. I had one in that hole only the crack was on the top to the big water hole. You would think the head gasket would seal it, but the water seeped through the crack under the head bolt into the exh passage. The bolt only went half way down the hole. I ran a tap down the hole all the way in to the exh port, cleaned the hole good with brake clean, coated the threads in the block real good with some kind of sealer, use a longer head bolt that went all the way in to the exh port and coated those threads and torqued it down. It never leaked. Your crack is on the bottom of the hole witch has a dead bottom. I think if you use a good sealer on the bolt you'll be alright. Walt
 
Even if there are no other "visible cracks," you should magnetic test for cracks anyway. Many cracks are simply not visible to the naked eye, even after the deck has been thoroughly cleaned. Also, the block can crack in places other than the top deck, but this is much less common.
 
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