Break-In Oil

Superman · 03-18-2002, 04:24 PM

You know and I know that we've beaten dead horses here before. So, let's whack this one a few more times.

Old Wives' Tale: Use non-detergent oil. I've heard this before and most of the authorities I go to now say "that was then...this is now. Use detergent oil!"

My sources say that Honda uses a special 5W-20 mineral (whatever that means) oil for a breakin period of 10,000 miles. That's pretty thin oil. I am going to be hoping my new rings will seat properly against my old cylinders. Thin oil like this might help, but might not be enough protection for the new bearings. I have a case of Kendall 20w/50, which I was going to use for break-in.

Any suggestions?

Doug Zielke · 05:40 PM

"Fools tread, where angels fear to go!"

So here goes, Jim....
I doubt it will matter what kind of oil you use (detergent, non-detergent, weight, etc), other than it should be distillate of dinosaur. And of course you know to change it at 250, 500, and 1000 miles along with the filter. Also, cut the filter open after each change. Pull out and examine the pleats for excessive metallic debris (which you hope not to find).

And for what it's worth...
When I had my boat repowered with new CAT 3208 diesels, the installing mechanic filled the crankcases with Shell Rotella T 15w-40, said to be a very good oil for *any* I.C. motor.

pwd72s · 03-18-2002, 05:34 PM

Gawd, I hate to say this

, but I agree with this SCWDP guy, I really do.

APKhaos · 03-18-2002, 05:57 PM

Jim,
Congrats! Sounds like you are nearly ready to roll. Mine is still coming together.
FWIW, the rings will reseal in the first few minutes of running. The bearings are the things that take time - following your choice of break-in routine. The biggest deal is that the rockers will bear on a new area of the elephant's foot, and can tighten up considerably. Need to reset the valves somewhere around 500 miles. No retorque required, just reset the clearances.

Doug is right [as usual] on the use of dino based oil.

MikeB · 03-18-2002, 06:20 PM

FWIW, aviation engines when new or rebuilt should be run with mineral (non-detergent) oil. Now to find a reasonably priced oil filter cutter...

RoninLB · 03-18-2002, 06:43 PM

I changed the oil filter only, after start up and before it hit the road.

Early_S_Man · 03-18-2002, 08:02 PM

Super JIm,

If 'thin' oil is the ticket to break-in, I am sure there is some Shell Rotella available in your neck of the woods ... in SAE 20W-20 grade! Assuming, of course, you don't get an 85°F heat wave this weekend!

Superman · 03-19-2002, 12:26 AM

It seemed to snow here most of the day today and my daughter made a huge snowball yesterday. 85 would be a record. Perhaps I'll try a thinner, non-detergent/mineral oil. Decisions, decisions.

Formerly Steve Wilkinson · 03-19-2002, 05:41 AM

If Honda uses mineral oil, they're essentially saying, "Break in the engine with unslippery oil and definitely don't use something like a synthetic." Which is what we do with aircraft engines. "Mineral oil" is what cars used before the development of detergent and ashless-dispersant oils. You need to seat the rings, among other things. If you put in real slippery oil, the cylinder walls will glaze, the rings will never seat, and you'll end up with the classic symptom of both bad rings and unseated rings: excessive oil consumption.

On a horizontally opposed, air-cooled, aluminum airplane engine, you see it very specifically, when the when the rings seat and the CHT and oil consumption both go down perceptibly, and it usually happens somewhere between five and 25 hours, though the general rule is to run mineral oil for the first 50 hours of flight, running the engine hard (75-percent power), generally steady-state but with power variations.

Yes, I know that Porsche breaks in its engines with Mobil 1, but they're doing it in a very specific factory testbed setting where they can control a variety of things you and I can't on the road.

Stephan

RoninLB · 03-19-2002, 05:55 AM

I used straight 30w non-det. oil for 750 mi. Made sure eng, temp. were conservative.Rings are tight, checked w/leak down and comp. test. Burns 1 qt/3000 mi. Tighter than a crab's ass and that's water tight. I used a "rock while rolling" technique to break in.

gaijinda · 03-19-2002, 07:04 AM

I just got my baby back on the road, but I would not put anything ment for a new Honda in an engine with a much older design... Air cooled as well. I am staying away from synthetic for now, and trying not to do too much highway driving, that is about it.

GIBSON · GIBSON's Garage

Ron, I'm planning on getting my 73 back on the road this weekend after 8 months of work. I'll be using a straight 30wt. to break in, change at 500 miles and again at 1000. Not sure when to make the switch to synthetic, probably after at least 2000 mi....
Are non-detergent oils readily available?

Bruce

RoninLB · 03-19-2002, 07:33 AM

Gibson...non-det is available at maybe $2-$3/qt. There was a small article by Bruce A. that clarifies the break-in w/non-det 30w. I could find it later if necessary. I switched to mobil 1 after testing/leak down-comp to confirm the crabs ass was tight. I changed oil filter only before hitting the road and only did full warm up drives, not small/cold eng. drives. I kept rocking the gas pedal to keep rings forced into cyl. wall. No cruse control type driving for me. I never hit 5th gear for 1000 mi. Probably over-kill, that's my problem. I would do hy in 4th at 3-4k after 300mi. and keep rocking.