What running in oil

[Gary.pb]

I'm a couple of hours or so away from firing up my new engine for the first time. I read somewhere that you should use one lot of oil and then do a full oil change after 500 miles. This is probably a silly question but do I use the same grade oil for running in the engine or do I need a different grade oil. The engine has been completely rebuilt with new bearings/ pistons etc and is effectively a brand new engine. The engine is a 1.9 dg.

Cheers

Gary

[kevtherev]

Same.

[Titus A Duxass]

^^^^WHS^^^^^

Use your normal oil, change it after 500 miles.

[bigherb]

Only use a mineral oil for running in, not a semi or fully synthetic as they will make it take longer for the rings to bed in.

[windy]

Only use a mineral oil for running in, not a semi or fully synthetic as they will make it take longer for the rings to bed in.

That is very good advice.
Its tempting to use a good oil in your freshly rebuilt engine but its counter productive. Use a cheap mineral oil for the first 500 miles & it will give the rings a much better chance of bedding in.
A friend made the mistake of using Castrol Magnatec oil after honing the cylinders & fitting new rings & he had serious crankcase pressurisation problems resulting from the rings not bedding in.

[California Dreamin]

Personally I would say use the cheapest 20W50 you can find for the initial bedding in but then I am a tight wad. The idea is the basic 20W50 mineral will allow things to wear in more easily than your normal oil.
Or even proper 'running in' oil, although not really necessary.
I know some on here have an aversion for anything that says synthetic but with a new seals and rebuild I would go for a semi synthetic 15W40 as you main oil.

Martin