Running in oil

[p.mole1]

How long should I leave it in? I have just rebuilt a 1.8 K with new rings, liners, bearing shells and a new oil pump. I am bit paranoid about glazing the bores. I have done 300 miles of spirited driving.

[Paul Mason]

Hi Phil, hope you're well, there are much much more knowledgeable than me on here so bear that in mind, but my understanding is the most likely cause of glazing would be constant and prolonged engine speeds (motorway driving and such like) and geussing that's not what you've been doing?

[p.mole1]

Thanks, I don't want to leave this oil in longer than necessary.

[Manstein]

I did about 400 miles with a rebuilt Duratec before changing.

[Jonathan Kay]

Procedure for my 1800 K after the rebuild.

Jonathan

[Paul McKenzie]

It's good to use a magnetic sump plug after a rebuild then you can see the amount of powdered metal sludge that collects on the plug, which gives a visual indication of when the running in periods are over.

I do 200 miles on cheapo 20/50, change oil for more 20/50 and repeat for 400 miles, then onto full synthetic.

[p.mole1]

Thanks will give it another 100 mile