Quote:
Originally Posted by TedEaton
Not to be an alarmist but that antifreeze on that rear main bolt would make me suspect a crack in the rear main bolt hole. The front four main caps have longer bolts than those two bolts in the rear cap (under the rear main seal retainer) and it's possible during a previous engine disassembly that one or two of the longer bolts was used in the rear main holes rather than the required shorter bolts. If this was the case, then the longer bolts bottomed out when being torqued in place and potentially cracked the block. Ted Eaton.
|
Ted is of course 100% correct.
The same info is shown at this link from John Mummert's website...
http://ford-y-block.com/assemblyerrors.htm
When Ford designed the 312 they made the main caps taller than the 292 cap, anticipating added load. The cap for the 312 rear main was left the 292 height, to clear the rear main seal holder and the oil pan rail. This makes it possible to install any of the longer main cap bolts from the front 4 main caps in the rear cap, where they could bottom out during tightening. Some blocks are drilled deep enough to accept the longer bolts in the rear cap. There have been a few instances where the rear main area of a 312 cracked during assembly. This was probably caused by installing the incorrect bolts in the rear cap.