A buddy (Kevin) has a 1991 F150 with a 302, auto in it. He said that he has been getting excessive oil in the air filter box and doesn't know where it is coming from. When he took the box lid off, the filter was noticably covered in oil. It had started to turn the filter a brown colour. When he lifted the filter out, the small air filter that attaches to the hose going to the top of the valve cover was also covered in oil and there was oil sitting in the bottom of the box. He said that he just changed the filters three weeks ago and he has changed the PVC valve twice so far. The engine is stock and needs a turn up. Any ideas here, I was thinking PVC valve myself but if he has changed it already. He says the truck runs fine, no odd misses or anything like that either. Your help is greatly appreciated.

Have Fun & Keep on Truckin'
Dean

 

Could be a bad sign, maybe blowby from worn rings.

 

that little filter in the air box is the crank case vent. take off the oil fill cap with the engine running, see if there is any smoke or anything coming out.

 

Thanks for the replies so far. I was following him last night and I didn't see any blue smoke from the truck. I will have to check the oil filler cap off tip and see what happens.

Have Fun & Keep on Truckin'
Dean

 

this is how my problems started out . i ended up with oil blowing out the top of my motor and a cracked head and bad rings . low oil pressure from worn out rod bearings . i eneded up replacing the motor .