what is the best oil for running in a engine rebuild

[miker519]

hi all I am rebuilding the engine on my Standard 1098 what is the best grade of oil to use and when should I change it
Many thanks MikeR

[svenedin]

The chap who rebuilt my engine said I could use any decent oil of the correct grade i.e 20w50 and no need for anything special so I am just using my usual Millers Classic Pistoneeze 20w50. He said to change the oil after 500 miles. So much is written and argued about when it comes to oils! The Millers Classic is a high zinc oil.

Stephen

[miker519]

cheer for that I will stick with the 20/50 then

Best regards MikeR

[northernboy]

I would add it you really want to help protect the engine, you could do say 500 miles and avoid labouring or racing the engine as part of the running in process. Then drain the oil and change the filter and then add a flushing oil to help remove any remaining contaminants from the rebuild. Follow flushing oil manufacturer guidance and then change again with normal oil and another filter. Draining the oil when warm ensures a quicker drain and also helps more oil to drain out. This should help ensure your new engine gets best start in its new life

[oliver90owner]

I don’t go along with all these oil and filter changes in quick succession.

Oil circulation to the engine bearings is through the filter. A high quality filter will remove virtually any particles which may damage the bearings. The rest of the oil will be directed through the PRV. A magnet fitted to the drain plug will likely indicate (and remove) any magnetic particles that may be circulating through the engine.

The oil pump is protected from larger objects by its pick-up screen.

A better way to prolong engine life, from lubrication woes, apart from regular oil and filter changes, is to fit a bypass oil filtration system - which will remove much smaller suspended particulates in the oil.

A fair quality of oil (but not one of the better synthetics), with plenty of detergent activity will be adequate for running-in purposes. It should only be there for about 500 miles of light duty motoring after all. A too ‘slippery’ oil may not allow proper bedding-in between bores and piston rings. A zinc additive would definitely be good for these older engines.