Just got my $25 1983 F150 running. Just needed a carb cleaning and fuel pump. When I first got it running it smoked for awhile but quit after about a 1/2 hour of running. As far as I know it has not ran since 2000 so I changed oil / filter after running it for about an hour. I'm concerened as to what is causing the lower end pressure to be blowing oil up and out of the dipstick tube. Just seems weird since it doesn't appear to be buring oil so I wouldn't think it's blow by. The odometer says 80,000 but would guess from the looks of the truck it's at least 180,000. Any other ideas other than blow by???

 

Check the pcv valve & make sure line is clean...If its been sitting scence 2000 replace it..

 

Do either or both a cyl. leak down test and compression test. If the numbers are good you have something else wrong but if they are low then you positively know you have blow-by and need to open up the engine.