Hey all...

Just noticed that it looks like some oil is burning when coasting down in gear, most especially when going downhill in a lower gear. It doesn't smoke otherwise while running idle, accellerating, nor driving along...it only does it when slowing down or coasting downhill in, say, third gear. Is this good, bad, or ugly? What, if anything, would this indicate as far as the engine's condition?

Just as a little background: The engine on this '68 just turned 116K miles. The first owner who bought this car brand new had it for its first 36 years of its life and drove it very little, and the stack of the receipts for every cotton picking piece of work he had done on the thing support that it's really 116K and not 216K+. The driving habits appear to be mostly short drives in the city, especially since he lived only 4 or 5 miles from work. I'd say that perhaps some components have become tired or worn from the city driving and from sheer age, so I would not be surprised if a valve job or something of that nature would be required. I guess I'm just looking for some troubleshooting advice to see what I may be getting involved in at this stage in its life.

Thanks!

- Dan

Well we used to just think that it was the valve stem seals (B18). Engine braking sucking oil around valve guides due to worn wafer seals on top of the valves. I don't know if yours is a B18 or B20 ('68 was a transition year) and although B20 seals are improved, they're a bigger deal to replace. More likely compression will show you it's worn (or broken) rings and it's sucking oil past the rings. Leakdown test?
Pop your hood and see if any oil is dripping out of the bottom of the front air filter. Blowby.
How is your oil consumption anyway?

Mine has a B18 converted to a single weber. I guess a compression test would be a good thing on this one...I'll check that out. I've driven it about 1000 miles across 2 oil changes since I first acquired her in February 2005. In that time, I haven't had to add oil and the oil level has remained consistent the whole time. The smoking isn't really a major problem (people behind me don't have to pull over momentarily for the smoke to clear, hehe). I guess I'm wondering if this is something that requires immediate attention or is this something that can be lived with for a while?

Right now I'm mapping a tentative schedule for its refurbishment, trying to get things at least mechanically reliable and then getting the repaint job done. I figure I'll get the paint done after I'm through greasing around so that the new paint job isn't damaged. In the end, I'm not trying to make this a show car so much as something that I can use for most everyday driving (work for me round-trip is maybe 25 mi) and occasional country drive down toward the beaches (about 350 mile round-trip) while still being presentable. :)

- Dan

From what you've added, I'd give the valve stem seals a shot, or at least a look/see. If you pull the valve cover and find that the rubber wafers (seals) at the top of the valves, sitting on the keepers, are hard, brittle, broken, or gone, get yerself 8 new ones. You have to back off on the valve adjusters to install and then readjust the valves, but not a big deal. I've seen where they've been so hard and brittle as to have broken and fallen off. If they're missing on top,look around on the top of the head and retrieve and dispose of. good luck

I agree that the likely culprit is worn valve guides, which is no big deal if the smoke isn't obnoxious and oil consumption is within reasonable limits. However, those B18-style seals on top of the retainers do just about nothing to control smoke on deceleration -- if you leave them off entirely, you'll get a brief puff of smoke on start-up, but no further smoke as long as the guides are not worn beyond spec.

where do you find those rubber washer things anyway? Standard part for cars, or a volvo special item? I need 8 new ones for "Spare Head #1"
--
1967 P220 Amazon, 1972 145S, 1976 245 DL, 1983 245 DL, 1986 745 GLE, 1990 745 GL, 1995 945....
You mean to tell me that Volvo makes cars that are *NOT* Wagons?!?

This is more than likely an annoying but not serious problem. I would guess
that the valve guides are slightly worn, and the high vacuum created with
engine braking pulls oil into the intake ports and thus burns it. The amount
of oil is small and unless you are using oil a lot faster than you like, I would
ignore it until you have some other reason to do engine work.
--
George Downs Bartlesville, Heart of the USA!