The Stovebolt Site Forums The Shop Area Engine Shop 216 Break-in oil change

I bought a 3100 with an '59 216 that was rebuilt 4 years ago and had about 100 miles on it. I changed the oil and used Royal Purple break-in oil. I have put an additional 250 miles on the engine. Any opinions how many miles to run break-in oil? Note the engine did not come equipped with the optional oil filter. Also, any opinions on a Royal Purple High Performance Synthetic 5-30w for this engine long term?

5-30 in any stovebolt is a HUGE mistake. These engines aren't designed for water-thin oil. I believe any oil with a lower viscosity number below 15 will tend to hammer out bearings and make the engine sound like there are dozens of little guys with hammers in there trying to break out.

I use 15W-40 in everything I own, from lawn mowers to farm tractors. No oil-related failures yet!
Jerry

That's what I was thinking. How many miles do you run break-in oil on rebuilt older engines?

With the possible exception of a bone-stock Babbit rod 216 or 235, 1,000 miles or so on the break-in oil shouldn't be a problem. A splasher engine will generate a bit more contamination as the bearings wear in to the crankshaft, so I'd recommend 500-750 miles on one of them. Modern parts are so much better machined and fitted than the ones we used 50 years ago that "break-in" is just about a thing of the past.
Jerry

Ain't that the truth! I bought a brand spankin' new 2014 Silverado small block last year.
Of course, I'm not one to read the instructions, only as a last resort. Couldn't put the
rear seat back down a few weeks ago, so I had to get the owner’s manual out to tell me
what thing to pull on to get it to release.
I was aware that break-in oil was as Jerry put it, "a thing of the past," with the new cars,
so I wasn't too concerned about that first oil change. After all, being a smart little truck, it
was estimating the oil life all by itself by calculating the engine rpm, temperature and
miles driven, and the display was telling me I still had 90% Oil Service Life Remaining'.
I’d already bought six qts. of Mobile 1 synthetic and a Fram filter, which was sitting on
the shelf for the first change. Even though I'd had the truck since the end of last
summer, when the 2015's came out, I still only had less than 5k on it. The dealer must
have had his timer running and figured I'd put twice that many miles on it, so they called
dangling a carrot in front of me, "bring your truck in for a FREE oil change." Well I was
taught early on that there ain't no such thing as a free lunch. I had this gut feeling that
this was some kind of a come-on to get the truck in the shop so they could tack on
some extras that weren't covered by the warrantee. So, apparently 15k on the breaking
oil seems to be ok by GM standards now a days, but I’d feel much better changing my
oil at 5k even though it’s extended life oil.
Now, to break in my 216 after the rebuild, I subscribed to old school philosophy in part,
and as Jerry posted, fresh oil after the first 500 miles to clear the cobs out. But, I didn’t
us a light breaking oil, which has always been thought to aid in lapping in the cylinders
to the new rings. I just used the same old 15w40 Shell Rotella-T that I use in the tractors
and that I’ve always run in the Stovebolt. I did ran it hard to break her in the first few
hundred miles. Must have worked out ok cuz I’m approaching 10k sometime this
summer and she doesn’t burn a drop of oil and in spite of the lack of an oil filter it stays
clean for the first couple thousand miles, which tells me there isn’t excessive blow by. I
do try to change out oil at about 3000 miles as its turning color by that point, which is
the indicator that I’ve been using in all my vehicles since 1956 and I’ve never had a
catastrophic engine failure, unless you count the midget engine.

Denny Graham
Sandwich, IL

A 59 216?

From the factory trucks came with SAE 10W.. that is 'water thin' (COLD the viscosity is 10.. not hot.)

A 15W40oil really isn't giving you any 'cushioning'.. its only increasing the oil pressure (at the gauge) and making it harder for the bearings to create a boundary layer film (viscosity = RESISTANCE to flow).

In a perfect world we would have the thinnest possible oil that would not shear or boil away under heat... generally that's a 20 weight oil... maybe a 30 weight in HOT climates.

A good 5W20 or 5W30 oil is probably the best choice. Truth be told any oil is better then no oil.

http://chevy.oldcarmanualproject.com/shop/1948_51truck/51ctsm0002.htm

A truck in my area would almost never need the diluted SAE 10 oil that GM recommended. If you do not drive in the winter (to avoid salted roads), a 15W-40 (or, a 10W-30) will do no harm and will be closer to GM spec.

" . . From the factory trucks came with SAE 10W.. "

Whatever weight oil GM put in at the factory, the factory oil was considered to be "break-in" oil (by GM) - it was supposed to be changed after 500 miles.