if your vacuum pump springs a leak

[swankmetal]

take a close look at where the oil's coming out. if it's at the red arrow, all your going to need is a new o-ring . found this out last night. i was losing 3-4 qts of oil in 2hrs drive time. got the seal/gasket/o-ring kit from cummins for 7 bucks and started taking things apart. when i separated the set-up at the red arrow (good place to start when everythings on the truck, only 2 bolts) i found that the o-ring was as brittle as hard candy. i took the vacuum pump completely off and investigated/cleaned it though. couldn't find where the seal would go on it, so i'm guessing it goes somewhere near the blue arrow. put the new o-ring on, bolted 'er back together and surprise! no more leak. soaked the underside with simple green for a while and then down to the car wash to get rid of the few GALLONS of oil under there. problem solved.

dave