Re: hairline crack in block....help!

Posted by custo eight On 2016/10/23 11:17:52

update....
block is at engine shop in Charlotte who is familiar with pinning and lacing engine blocks. They will sleeve the cylinder after pinning just to make sure. Fish'n Jim, the cylinders have been honed as evidenced by the markings on all cylinder walls. Not sure where the "shadow lines" are but they are there in most if not all cylinders. Could be removal of hone device making vertical striations. Have not tried wiping them clean. They certainly are not perfectly parallel cracks.
Interesting observation when removing the block from the back of my expedition. In the bright sunlight, it was obvious the adjacent valve had been pinned in exactly the same area of the valve seat. front to back. That pinning had to be done prior to 1957 when the car came into my family...I was 9 years old. My dad did all of the work on the car, replaced valves while I was still in HS 1965. Drove it in college in 67 and 68 then it was parked. The car was not touched again engine wise until 1987 when he started a rebuild. He was 68 at the time...my age now.
That pin may well have been put in at the factory to correct a casting flaw or shortly there after. It was a low mileage car in 1957 as it had been exclusively a funeral home limo. I believe it had under 30K miles when dad purchased it. Tons of room for speculation, however, after 100008 miles, I guess two cracks isn't too bad given the nature of the beast and the challenges of producing the 356 block.