Hello to all you Cat guys in this great club. I have a nice starting and nice running starting engine on my 1942 D4 but it leaks engine oil bad into the pinion housing and then out the main clutch compartment. I know that originally it depended only on groves in the crankshaft to keep the oil in being there is no seal there like on the flywheel end. Puzzling is the fact that there is no leak on the flywheel end which would be expected on a worn crankshaft and bearings, and that flywheel end bearing does not feel like it is worn bad.
It seems like there should be some solution other than a complete overhaul of such a good running engine. Does anyone have any ideas like perhaps Cat may have made a field changeover and added a seal on that end later? I though I had a solution by letting the pinion housing just fill up as it worked fine being overfilled but then all of a sudden it really started coming out the bottom of the main clutch. I have had other engines leak oil at the flywheel but still not have this bad leak at this end so it has me wondering. Very likely the previous owner run it low on oil causing destruction of this drive end first but still not show wear at the flywheel end yet.
I really do not think there is any solution other than a complete tear down and rebuild but just am looking for confirmation on my own thoughts.