Spitting oil from exhaust at start up, normal?

[Tim Brillon]

As the title says my new to me 63 Super 90 blows a bit of oil at start up onto the garage floor. It extends about 2' behind the car and is a very light mist of oil. Is this normal?

Car runs fine otherwise and sits for 1-2 weeks between drives. When it is driven I go about 20-30 miles per trip. Car leaks a couple of drops of oil after each drive.

[David Jones]

Tim, I find it hard to believe it is oil. Oil would present as a blue haze as it would not transit the engine unburnt. It is more likely you are seeing water condensate from burning gasoline. Burning one gallon of gasoline will produce about one gallon of water which once the engine and exhaust is up to operating temp is not very noticeable as it does not condense near the exhaust outlet unless the ambient is very low.
Hold your hand in the exhaust plume and you will find that you will have soot and water precipitate on your hand.

[Ron LaDow]

Not 'normal'.
A bit of oil smoke is common, since the cylinders are horizontal, don't drain well and burn the oil remaining in the chambers on start up, but spitting oil onto the surface aft of the car is not common. I dunno what would cause that.
Only a couple of drips after a ride says you have a well-sealed engine or are out of oil.
(late in answering; looks like David has it)

[Tim Brillon]

Thanks, it looks like it is soot. It just sprays out so fine when starting up that it looks like a mist of oil on the floor. I rub the floor and it smears like oil would but then when I rub my finger inside the tailpipe it has a buildup of soot, not oil. Sorry for the dumb questions, this is my first "old" car

[Mike Wilson]

Not a dumb question at all, Tim. It shows you are paying attention to your car.

Mike

[Ron LaDow]

Thanks, it looks like it is soot. It just sprays out so fine when starting up that it looks like a mist of oil on the floor. I rub the floor and it smears like oil would but then when I rub my finger inside the tailpipe it has a buildup of soot, not oil. Sorry for the dumb questions, this is my first "old" car

Now, when the next newbie asks, you get to pass on that info; you are now no longer a newbie.

[Dick Weiss]

During several engine teardowns, I've found that the piston ring orientation are/may be correct on 1-bank, but the other side isn't due to turning the engine over (on the stand) and not orienting the rings in the proper direction--especially the oil ring! Of course, the cylinders should be round and straight w/in specs including the piston OD-to-cylinder-ID!
3-ring pistons should have the ring gaps 120 degrees apart and 4-ring pistons should have the ring gaps 90 degrees apart.

However, the ring-to-piston-groove side clearance can influence oil usage if worn past their maximum limit(s) including their gaps.
Deves can supply oversize/thicker rings if the piston ring/grooves are re-finished--if the piston OD's aren't worn out; I've done several.

The original S90 Ferral cylinders didn't last as long as cast iron (pending on keeping the oil clean). but having the Nickasil 'treatment'
cylinders may/will last longer along w/coated piston skirts. Big-bore PCs are available w/full cast iron cylinders or cast-on aluminum fins
like the original Biral cylinder kits from Mahle. The original S90 cylinders were completly machined including the fins; then "Ferraled".











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