I was told by a local engine builder that he uses non detergent motor oil when he runs an engine for the first time on the engine dyno. He claims it seat the rings better. Has anyone heard of this before. He also mentioned he puts a bottle of EOS in with the non detergent oil.

 

I understand that non detergent oil was the recommendation of choice years ago, but unless your engine will be broken in, on an engine dyno, IMO, it is far more important to use the correct procedure than to be concerned with choice of detergent or non detergent. As far as oil is concerned, I would definately stay away from synthetic, which will be less effective for proper ring seating.

I realize there are some here that recommend the non detergent. Maybe they can shed lite, as to why it is still recommended or necessary, for the most effective seating, with today's ring technology and wall prep being superior to that of years ago.

 

Most of the web site I found and engines I have rebuilt, use just detergent 30w or 10w30 dyno oil for break in...

Found this...

It is important to use heavy-duty detergent oils which contain an EP (extreme pressure) additive right from the start. Special "break-in" oils should not be used unless specified by the manufacturer. Older engines without oil filters may require special considerations, such as the use of non-detergent oils unless otherwise specified by the manufacturer.

Consult the owner's or service manual for the latest manufacturer's recommendation on oil selection.

 

It doesn't HAVE to be non detergent(I prefer it) but do not put in synthetic it will slick out the cyl walls and cause the rings not to seat.Some addivatives in regular oil will too.I use ND for the first 1000 miles and never had a problem since the '60's.Some will disagree but I know ND works and have had no problem on rings that are hard to seat(chrome,stainless)even with the proper hone job.

 

What my builder uses for break in is Shell Rotella 15w-40 for Diesel trucks. He said that it has all of the right detergents in it for breaking in a new motor. This is used in combination with a Wix Racing oil filter. The oil was changed after the first 20 minutes on the dyno, and filter cut open for inspection. Then it was run for a few hours with a few pulls made to get the rings to seat and get everything to settle. Oil was dumped and filter cut open again for inspection. After getting it in the car, filled it with 6 quarts of Rotella and a K&N oil filter, drove it for 100 miles, changed it again, then 500 miles, changed it again. I will do one more oil change with the Rotella, drive it for 500 miles then switch to Mobil 1 5w-30 synthetic. I want at least 1500 to 2000 miles of breaking it in before I go for some 6500 RPM WOT upshifts . For now I only go 1/2 to 3/4, sometimes WOT till about 5000 RPM, dont want to go too easy on it



Nick

 

What do you find in the inspection of the oil filter? Metal shavings, obviously, but how much? Does it decrease with each oil change?


<----- Never rebuilt anything

 

You will find some material in the filter media, from the parts settling in and getting "happy" as my builder says. We found some metal from the valve spring shims in the filter, this was due to AFR not installing hardened shims This was fixed and dynoed again, and there was nothing but normal amounts of break in wear in the filter and oil. Yes, I did notice that the oil gets much cleaner with each oil change that i do, as this is normal for the first few.



Nick

 

When I built mine, a really good friend (the engine doctor) of mine told me to use 30wt non-detergent oil.

He stated that it didn't wash away the pre-lube out as quick as detergent oil did, and everything would break in better.

That's just what I was told, so I did it, and everything is happy so far. 7000rpms happy.

D Moss

 

Most articles online state that it is preferable to use a standard 10-30 detergent oil for 200-500 and no more than 1000 miles for break-in. Most would agree that synthetic is best after that. Several of the articles stress not being real easy on the engine, and point out that higher rpm would lead to better ring lands. Cams require the first 20 minutes be unsteady rpm between 2000-2800 or so.