[ursus]

Any sealer or epoxy repair will be severely tested in an exhaust port or exhaust valve pocket location. The area is subject to the highest temperatures of any part of the Model A block as well as to internal pressure exerted by exhaust within the port.

Cracks in this area are rare in a Model A but may be less rare in a Model B because the "B" casting walls are thinner, especially in the #2 and #3 exhaust ports. Cracks will result in coolant leakage into the exhaust manifold and, if the crack is large enough - or there are pinholes, the result will be exhaust leakage into the coolant as the engine is running.

I have a "B" block that is crack-free except for a 1/16 inch pinhole that is open to the mid-block coolant chamber. The pinhole is about an inch below the deck in the upper valve pocket. I have pondered some solutions, such as pinning the pinhole or hogging out the port and pressing in a sleeve. Any suggestions?