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Hi All,

1941 super 8 with a fresh rebuild. Compression test seems to be good.


cyl-(PSI)
1---100
2---95
3---98
4---92
5---95
6---95
7---100
8---100


I just changed all the spark plugs because they were all coated in oil and the car was misfiring. The car only has about 10 hours of run time, ~90% at idle.

I do remember seeing some oil in the intake after a hot shutdown/restart with some oil smoke out the tailpipe, but in general the engine seems to run good with no obvious signs/smells of blow-by.

I do have a PCV hooked up from where the draft tube used to connect, but there doesn't seem to be any obvious signs of excessive oil re-circulation via the PCV vent, and the event mentioned above was before the PCV was hooked up (I think). It could be possible this is in fact the cause, but I keep thinking of the amount of oil I remember seeing in the intake.

Just wondering if there are any known causes unique to a super 8 that could cause oil getting into the intake manifold (i.e. a part left out during the rebuild, etc.) and cause plug fouling.

A breached diaphragm in the vacuum pump can let that happen.

What is your reason for idling so much? That is bad for any engine, but especially so for a fresh rebuild as the rings need lots of oil thrown up.

Thanks for the Reply Ross.

I actually doubt I have *that* much idle time on the car. Probably more like 5 hours. Idle time is mostly just because I still have body panels off of the car and other projects going on, so yet to really get it on the road.

I think you might be on to something with the vacuum pump. It looked to be a fresh rebuild, but has been in a hot and dry environment for ~ 4 years, and on a shelf for who knows how long before that. I quickly took the tube from the fuel/vacuum pump to intake off and noticed some oil on the on the fuel/vacuum end of the tube. Nothing excessive, but I am assuming there should be *no* oil.

I would guess a diagnostic test would be to pull a vacuum from the inlet and plug the outlet and make sure it holds (I am sure that there is a diagnostic test in some packard literature one of the gurus could post)?

So I pulled a vacuum on the vacuum pump side of the fuel/vacuum pump and it did not hold a vacuum, but, it wasn't a huge leak.

20-15 in-hg ~ 5 sec
15-10 in-hg ~ 15 sec
10-5 in-hg ~45 seconds
5-0 in-hg ~ 2 minutes

I think i'm going to loop the vacuum pump for now and "collect more data". I did suck out some oily fuel from the bottom of the manifold, but it seemed to be more gas than oil.

I guess I should also make sure the gas side of the pump isn't leaking oil into the fuel.