View single post by Dan (Florida)
 Posted: 01-12-2011 01:42 pm
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Dan (Florida)

 

Joined: 03-16-2005
Location: Ormond Beach, Florida USA
Posts: 97
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I recently pulledd the engine out of my 73 in order to replace the rear main oil seal (rope) . This requires removing the crankshaft in order to fit the new seal which has to be trimmed to length after pressing into place. Upon removing the main bearing cradle and connecting rod caps and lifting the crank out  I find the main and rod bearings were worn down to the copper backings. I miked the crank out and found it in very good shape and ordered a standard sized bearing set from the club store. The rod bearings went in fine and turned smoothly but the mains tightened up when the bolts were torqued down and would not turn. They plastigauged out to .003"  and the bearings installed without the crank and tightened down  were snap gauged and miked to the same. Still the crank would seize when tightened down.  It ended up being the main bearing shells were too long and stuck up out of their races slightly.  Trimming them down with a file solved the problem I hope, and  theorize that when the engine was being machined at the factory the crankshaft align boring process got off center and took too much out of the block and too little out of the cradle. That being said I hereby cross all fingers and hope this ends the Christmas engine pulling jamboree. Im waiting for warmer weather for the engine start.

ps   this is the second rear main seal I have installed since this project started. The first came from Delta wrapped in paper with no instructions, (Fail)  The second was an oem seal  from Delta with instructions trimming gauges and lube.  (better I hope).

PPS  During all this the water pump seal gave out . Not satisfied with the price of a replacement from Delta I found a pump seal from Pac-seal from a local plumbing supply that provided the ceramic ring that was needed for a vastly cheaper price.  (This job is not for the inexperienced)