Slobbering oil outta muffler pipe? D4D

Hey guys I overcame a D4D 68 model with a direct drive hand clutch with a hyster 4 wintch on the rear, well first off when I got the lil dozier I had to learn how to drive one with a hand clutch an let me say it was a heck of an experience ,,, first off I had to load it on a lowboy first off an yuppp it happened ,, I had a brain fart an froze up an turn the boy 90 degress an off the side of the truck, needless to say after I got it home an it sat for 2 yrs I finally got the nerve up to play with it an paint it up an repair a few loose pads, an now after its been painted the motor has decided to slobber oil outta the pipe while running, I had ran into this few yrs ago on a cat 525 skidder after building the motor the guy let it run for hrs at a idle an the the rings glaved over an I cought heck making it stop, so when I first got the d4 I didn't notice the oil leak from muffler,,, ive got on ,it a pushed around with it a low or mid range rpms an it pushs a little oil from muffler,,, though it may of been the vent tube stopped up, removed it an didn't make a differ. so I removed the exhaust manifold an looked into head ports, all 4 of em are wet from oil,,, this is like my second encounter of this happening to a motor,,but this is the first time its been to a used motor an not a fresh rebuild,,,i though to myself for sure a 4 pistons are not slobbering oil. im trying to get outta doing a motor job to it,, cause im in the market to do few repairs an sell it . does anyone have any ideas ,,like I say I really don't wanta build it but I will if needed, also does anyone have any idea of that the tractors worth,,,, it has limb risers an has the rounded top not the average square, also it has the heavy expanded steel mesh around cab an a hyster 4 winch on rear an a great undercarriage,,, has been replaced before an I just painted it an new decals, other than oil leak from muffler over all its a pretty good running lil tractor an steers an drives an starts great, I was gonna ask bout 8500 bucks for it an see how it goes but I have seen some for 9000 to 16000 bucks

Slobbering oil outta muffler pipe? D4D