Im about to put a brand spanking new engine in my car and im a little unsure of what oil to put in it for the running in period. If anyone could recommend a good running in oil for me to use i would really appreciate it.

cheers luke

Im about to put a brand spanking new engine in my car and im a little unsure of what oil to put in it for the running in period. If anyone could recommend a good running in oil for me to use i would really appreciate it.

cheers luke

go with what mitsu factory fill new engines with..... i believe its a 5w/30 ...

Luke, for running in preferably you want an oil free of viscosity index improvers and friction modifiers. Some oil sold as running-in is multi-grade so thats no good, it has VI improvers, long chain polymers added. These polymers can break up and lube loss can wipe the cam lobes out. This is a big problem with stiff valve springs and new/reground modified cams. Friction modifers are good for more power and better fuel economy but make it a lot harder for the rings to quickly bed-in.

A good basic oil is Valvoline Premium Mono. Get 30 grade if you can. Repco should have it for about $30-35/5ltr. You may find it in mower shops too.

An alternative is the same brand but in 40 grade. I wouldn't use that in winter but in summer its OK. That is used in GM Detroit 2 stroke diesels so can sometimes be easier to find if you can't get 30 grade.

Only use running-in oil for 500-600km, or if its using oil going to 1000km may help the rings bed. Then drop the oil and filter and fill with your regular oil. If its still burning oil after 1000km the hone job was probably not good so you might want to try a motorbike oil for 5000km, about 15-40 grade (10-40, 20-40 are OK too), but not a synthetic or semi-syn. Motobike oil doesn't have friction modifiers so this might get the rings/bore mated. Also because bikes often have a common g/box and engine sump the quality of polymers used is generally better/more expensive to avoid being chopped up by the gears.

Cheers,
Alan

Thanx Alan thats just the info i was looking for and knew i could count on you to provide it.

cheers luke

As Alan stated, you want a basic oil without the extra crap in it such as the friction modifiers etc.

Also, in ALL my motors I run in, I tend to drive them fairly hard so as to ensure good gas build up under the rings and good seating

There have been many articles written about this and some have in the past been put up on the forums as well

As Alan stated, you want a basic oil without the extra crap in it such as the friction modifiers etc.

Also, in ALL my motors I run in, I tend to drive them fairly hard so as to ensure good gas build up under the rings and good seating

There have been many articles written about this and some have in the past been put up on the forums as well

Just to add to Mal's comment. Rings need gas pressure, but only for relatively short periods otherwise they can glaze or the bores can glaze. You really need to drive like a typical Sunday dope, on and off the throttle. Holding a constant light throttle is the worst thing you can do. The engine needs heavy acceleration from about 2000-2500rpm in a high gear for 15 sec. Then lift off and coast so that the rings cool and oil gets sucked up the bores. Do this a dozen times every 0.7 -1km. Don't let the engine idle, so if you get stuck at lights keep the revs at 1500rpm minimum, and if running in a cam keep above 2000rpm.

If you have an auto then drive in tippy mode. Best is to drive away from traffic on twisty roads with lots of elevation changes. Repeat the 15 sec heavy load routine every 50 km until you have about 500 km on the engine. The rings should be run in before that but some hone jobs leave a lot to be desired so a few extra load routines will help the ring seal.

Cheers,
Alan