Seals were all intact and look good. However are the plastic ones better or preferable to the rubber ones? I did notice that they were all stuck up in the air rather than being seated on the bottom of the stem but presumably this is normal? Next time they could all be at the bottom.
I have no idea whether rubber or plastic ones are best, but what I do know, is that many being sold today apparently are not oil resistant. It seems this wasn't the issue in your case though. They move with the valve stems indeed.
With a V engine, I think that this sort of oil seal, one that goes up and down with the valve, is a rather odd choice. It might even tend to pump a bit of oil down into the guides if there is any splashing around that area. Vacuum will also assist it. The Volvo B18 engine has a domed rubber cap on top of the spring retainer cap and this is supposed to stop oil that would otherwise settle in the recess where the valve retainer collets are. The B18 is a vertical engine so that's reasonable. With a V engine, the angle of the retainer should mean the oil tends to run off so relies less on a seal that stops oil running down the valve stem. Repro rubber caps for the B18 can also be poor quality and split or break in half after very few miles so Melle's comment also applies with them. The later Volvo B20 does have proper seals that are retained on the head, some with a spring ring like similar Ford types. Guide length in the B20 is much shorter than the B18 which has its plus and minus points. None of that solves your problem but the V4 seals are still #1 on my list. Could be that the PCV system on your engine is a bit tired and causes the rocker area to be under more vacuum than normal. The oil could just be getting into the combustion chambers on one side. There were posts about having an adequate flow in a pipe that goes to the bottom of a filter on a Weber conversion causing problems. Who was that?
quote:Originally posted by Derek ... The new seals seemed to go up and down with the valve rather than staying fixed against the guide...
That is how it is supposed to be. They are clamped on the valve stem and do not really touch the guide. Oil runs off on the outside of the seal, drips on the top of the head and eventually into the sump.