Leak off line of alternator vacuum pump

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Location: Seattle
Isuzu vehicle(s): 1984 Diesel Isuzu PUP c223

Leak off line of alternator vacuum pump

Postby Fulcrumwoodwork » Tue Jun 11, 2019 12:29 am

‘84 2.2 Diesel engine:
Hey all, I found a good amount of oil residue on two hoses coming from the vacuum pump, but no dripping. The larger one goes from the pump to brake master cylinder, the small one goes from the pump to fuel pump (I think).

This is a pretty dumb question, but is oil even supposed to be in those hoses? Or air?

Second, also, is it true that the hose that goes to the brakes has a one way check valve inside it? I didn’t know this until just now when going through threads on the forum. I’m fairly sure I replaced that hose a while back with a hose that didn’t have a check valve. I presume that having that check valve in there is necessary.. correct?

Thanks, and sorry for the silly questions..