jlaird
Great Pumpkin
Offline
Installing the rear main cap cover correctly:
When overhauling an engine, it is not absolutely necessary to disturb the positioning of the rear main cap cover. I chose to remove mine due to concerns about destroying the cover-to-block gasket material during hot-tanking of the block. I left this cover off while checking bearing clearances with plastiguage. I then removed the crank and installed the rear cover/cover-to-block gasket in the following manner. After coating the gasket on both sides with Permatex Aviation Form-a-Gasket #3H I positioned the cover and tightened the three bolts firmly to squeeze out excess sealer before loosening them up a little so the cover could be moved around as much as the bolt holes would allow. I placed the crankshaft on the lubricated bearings and pushed the rear cover tightly against the crankshaft sealing surface before tightening the rear cover bolts to approximately 1/2 final torque. This exactly centers the rear cover, but leaves the rear cover too deep against the crank. (When the main cap is installed, the rear cover will be pushed away from the crankshaft sealing surface the proper distance). I then installed the rear main cap (with lubricated bearing) and torqued it to specifications before tightening the rear cover bolts to final torque. The crankshaft should spin freely without any rubbing on the rear cover. If not, the adjustment sequence will have to be repeated. After removing the rear main cap again and cleaning the cap mating surfaces with carburetor cleaner on a rag, <span style="color: #FF0000">I coated part of the rear main surface on the block from the "oil sealing surface" on the crank out to the edge of where the rear main cap would fit with Form-a-Gasket #3H, being careful not to use too much.</span> All main caps were then installed and torqued to specifications.
I bet I have read this 50 times. What is he saying where I have highlighted?
When overhauling an engine, it is not absolutely necessary to disturb the positioning of the rear main cap cover. I chose to remove mine due to concerns about destroying the cover-to-block gasket material during hot-tanking of the block. I left this cover off while checking bearing clearances with plastiguage. I then removed the crank and installed the rear cover/cover-to-block gasket in the following manner. After coating the gasket on both sides with Permatex Aviation Form-a-Gasket #3H I positioned the cover and tightened the three bolts firmly to squeeze out excess sealer before loosening them up a little so the cover could be moved around as much as the bolt holes would allow. I placed the crankshaft on the lubricated bearings and pushed the rear cover tightly against the crankshaft sealing surface before tightening the rear cover bolts to approximately 1/2 final torque. This exactly centers the rear cover, but leaves the rear cover too deep against the crank. (When the main cap is installed, the rear cover will be pushed away from the crankshaft sealing surface the proper distance). I then installed the rear main cap (with lubricated bearing) and torqued it to specifications before tightening the rear cover bolts to final torque. The crankshaft should spin freely without any rubbing on the rear cover. If not, the adjustment sequence will have to be repeated. After removing the rear main cap again and cleaning the cap mating surfaces with carburetor cleaner on a rag, <span style="color: #FF0000">I coated part of the rear main surface on the block from the "oil sealing surface" on the crank out to the edge of where the rear main cap would fit with Form-a-Gasket #3H, being careful not to use too much.</span> All main caps were then installed and torqued to specifications.
I bet I have read this 50 times. What is he saying where I have highlighted?