My son and I just finished building a box blade from scrap (I'll post pics and a description later) and I was pulling my 126 in the garage. I heard a tapping noise
under the hood. I pushed the clutch, idled it down and turned off the key.
The engine continued to spin with no compression.
I eased out the clutch with it in gear to stop the engine. I've heard engines "sling a rod" before. This was much quieter, maybe because of the heavy block. After removing and disassembling the engine, this is what I found.
According to the PO, I am the third owner and the engine has never "been into". If so, this is a very good track record for a 1971 tractor.
I've checked the cylinder bore, crank pin diameter, cam and crank shaft end play and cylinder head for flatness. All are within specs. Crank pin has some visible lines, but none can be felt. It looks like either the rod suffered from metal fatigue or one of the rod bolts loosened. 1 rod bolt was laying loose in the oil pan.
It may take a few weeks to get the money to order parts. That's one of the major problem with being disabled and on a fixed income.