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TOM CAT
08-30-2017, 10:01 AM
Hopefully this is a pretty easy question. I have a 1925 Big 6 all original that I have not started in a while (2 years) and want to change the oil before I start it up. I don't want to hurt the motor when I start it up. Just want to know what is the recommended oil for the Babbitt rod engine sense the oil pressure is so low. Experienced help with this type engine is much appreciated.

Mike Sal
08-30-2017, 01:26 PM
I'll let others weigh in on the type of oil, but if it was me, I'd leave the ignition off & crank the engine over several revolutions just to get some oil splashed up into the joints before trying to start it.
Mike Sal

jackb
08-30-2017, 04:08 PM
So..... realistically, this vehicle will be for occasional cruise nights and maybe parades ??? I'd simply put efforts into brakes and cooling.... then, get a good, hot oil drain. Some advise a 50/50 mix of non-detergent/HD oil, then with subsequent oil changes increase to complete HD oil. Your call. I wouldn't be so anal about that.....Its likely that the past 2 years might be the shortest nap this car's taken in near 100 years ! In that case changing oil is of little consequence in the big picture. Any service expectations beyond the above would suggest looking towards a complete engine rebuild...

Bud
08-30-2017, 05:17 PM
I would say that any good SAE 30 or 40 would be a good choice for that old engine. This is what I've used in Ford Model A's for years. I also don't buy into the theory that a modern oil with a good additive package will cause sudden death to the engine due to sludge being dislodged. and plugging something. A modern high detergent oil will clean up the inside of the engine, but that happens at a slow rate. Keep in mind that the really old engines survived with just about anything resembling oil poured into them. Bud

TOM CAT
08-30-2017, 08:09 PM
I would say that any good SAE 30 or 40 would be a good choice for that old engine. This is what I've used in Ford Model A's for years. I also don't buy into the theory that a modern oil with a good additive package will cause sudden death to the engine due to sludge being dislodged. and plugging something. A modern high detergent oil will clean up the inside of the engine, but that happens at a slow rate. Keep in mind that the really old engines survived with just about anything resembling oil poured into them. Bud

Thx Bud for the answer I was looking for SAE 30 or 40 is what I was needing to know.:!:

Bud
08-31-2017, 08:26 AM
You're welcome. Some people will tell you to use something like a 5W-30, 10W-30 or 20-50 oil in an old engine which will probably work, but I don't think they are the best answer as the bearing clearance in older engines is usually a bunch larger due to wear. The multi viscosity oils will act like an SAE 30 or 50 when hot, but are much thinner when cold which could cause lower oil pressure in an engine with some miles on it. You could also use something like Shell Rotella 15W-40 or Chevron Delo 400 15W-40 heavy duty oil if you are planning on running the engine in cooler weather. Bud

jnormanh
09-01-2017, 05:20 PM
The worst oil available today is miles better than the best oil available when the car was new.

If the engine has been rebuilt and it's known that the internal clearances are within a few thousandths, I'd run any of the 15W40 or 20W50 oils. Whichever brand you choose, it will be more than good enough.

If the engine is old and tired, maybe add a can of thickener like STP.