Minor Engine Questions

[dawolf]

My MR2 seems to be running okay although I just want to check on a couple of things (engine related):

1) My engine seems to burn a fair bit of oil, I have to top up with half a litre every 4-6 weeks I reckon, is this normal considering I rev it quite high? Engine has covered 70k miles.

2) When my engine has fully warmed up or on a hot day it seems to idle at 1000rpm for a second then it slowly drops down to 750rpm and stays there, it never cuts out though, is this normal for a hot engine?

Cheers.

[KiwiMR2]

1) My engine seems to burn a fair bit of oil, I have to top up with half a litre every 4-6 weeks I reckon, is this normal considering I rev it quite high? Engine has covered 70k miles.

Are you running a synthetic oil? I remeber back when I had my NA it used to EAT synthetic stuff really quickly so I switched to a thincker oil and it was MUCH better. Worth a try, sometimes they just don't like the thin stuff.

When my engine has fully warmed up or on a hot day it seems to idle at 1000rpm for a second then it slowly drops down to 750rpm and stays there, it never cuts out though, is this normal for a hot engine?

Sounds right.....higher revs are usually for when the car is 1st started as the engine is cold, then it drops down....I'd have to check mine to see if it goes down to 750 though. Apart from 1st thing there isn't really any occasion the engine needs to high rev at idle.

Cheers

KiwiMR2

[dawolf]

I'm currently using 10w40 stuff, I believe that's what Toyota recommend. Need to do an oil and coolant change soon actually.

[KiwiMR2]

Maybe try a 20w-40 this time around, see how it lasts :)

As for the viscosity of oil to use, most new engines today require a multiviscosity 5W-30 oil for all-round driving. The lighter 5W-30 oils contain friction reducing additives that help improve fuel economy, and also allow the oil to quickly reach critical upper valvetrain components when a cold engine is first started. Most engine wear occurs immediately after a cold start, so it's important to have oil that is thin enough to circulate easily -- especially at cold temperatures.

For older engines and ones that are driven at sustained highways speeds during hot weather, 10W-30 or 10W-40 is a good choice. Heavier multiviscosity oils such as 20W-40 are for high rpm, high-load applications primarily and are not recommended for cold weather driving.