Babbit vs HD oil multi viscosity
- Thread starter josh1331
- Start date
marc hildebrant
Well-known member
Josh,
That comment does not make sense.
Marc
That comment does not make sense.
Marc
john in illinois
Well-known member
No.
MikeK
Well-known member
Many "modern" insert bearings are of a layered design with a mere 0.0005" of babbitt at the surface riding the oil film between the bearing and the crank. If HD oils (I assume you mean current A.P.I spec) are safe for babbitt that thin, what could they possibly do to poured babbitt that is 80-100 times as thick? As far as multi vis. goes, the reason is to insure excellent circulation in a cold engine with an oil that will end up as thick as a straight weight when it gets to operating temperature. The disadvantage to using modern A.P.I. multi weight oil is the next restorer after you does not get the original experience of scraping sludge with a knife and screwdriver during the engine rebuild.
Mike, out of all the posts ive read on here you are one of the few that knew what you were talking about,your right, modern car bearings have a layer of babbit as a wear surface, and hd detergent oil does not hurt them, they can go over 200,000 with out an over haul, thats testament enough to prove detergent oil does not hurt engines, and your right use detergent and pass on the scraping and brushing sludge out of your engine at rebuild time, youve earned your title as senior member in my book
john charlton
Well-known member
I use low budget 20/50 multigrade but must have an API rating. Used this type of oil since 1985 with no ill effects .I change the oil as soon as it begins to go opaque on the dipstick.Around 1000 miles or so. The myth started here in England when Shell introduced "X100" HD multigrade. This was late fifties early sixties. Up to then oil was straight and came in sealed glass bottles or more commonly sold by the jug from a hand crank dispenser. Unwitting motorists tipped the new multigrade into their elderly high mileage engines and the high detergent oil sluiced years of sludge into suspension and of course with cataclysmic results. Hence the new oil was bad for babbitt . I advised my mother in law NOT to let the nice lad at the filling station put multigrade in her 1933 Morris Twelve . Came back from sea to find the car had died from terminal bearing failure . The nice lad had told her the new oil was better,it had to be of course, it came in a nice shiney red and gold can with a pull tab. Much nicer than from a jug.I did a post mortem on the engine it was lovely and clean allright, with the gloop and babbitt in the bottom of the pan.Moral of the story is if the engine has been run on straight oil for years dont put multigrade HD oil in it.If the engine is clean internally multigrade is way the best for it.
john charlton
Well-known member
PS John in no change in the weather England.
Mike V. Florida
Well-known member
High Detergent and straight 30 is like apples and oranges. One has nothing to do with the other.
ALL modern cars have babbit bearings (inserted not poured) and what do you use in your car? I bet HD Multi-viscosity oil?
Your A is no different!!!
High Detergent, no detergent, straight weight, multi weight, all will work with no problems.
Uncle Bob
Well-known member
Just to demonstrate the problem with "...some guy told me..." the HD on the can is nebulous. It's not a specification controlled nomenclature such as API S or C series designations. It's put on there by the marketing department. "You want it to mean high detergent? Okay. You want it to mean heavy duty? Okay. Whatever makes you feel good."
Now by practice what it most often means is the oil carries an API C series qualification intended for diesel engines (which would mean they aim it toward those who interpret Heavy Duty) and sometimes an S series for gasoline engines as well.
Now by practice what it most often means is the oil carries an API C series qualification intended for diesel engines (which would mean they aim it toward those who interpret Heavy Duty) and sometimes an S series for gasoline engines as well.