General oil level question..

If the oil level has been overfilled slightly say 2-3mm above the Max line, besides causing potential oil seal problems, would the amount over filled be burnt off overtime?

Curious.

I would have thought so matey

Cheers

Ian

It depends if your engine is an 'oil burner' or not. Mine doesn't use any oil at all (well, not that I can measure on the dipstick between 3000 mile oil changes).

Is it above the max line when hot or when cold??

If its when hot then there's no issue really. If its when cold then its too overfilled and some should be drained.

The max mark on the dipstick is for measuring with hot oil. When its cold it drops about 4 to 5 mm, so if its already over when cold then it will be 8mm or more over hot!!

 

The max mark on the dipstick is for measuring with hot oil. When its cold it drops about 4 to 5 mm, so if its already over when cold then it will be 8mm or more over hot!!

Isn't it the other way round, as when its cold, it all drains down to the sump?

I have always found that when cold my oil level is just around Max, and once its warmed up and the car is switched off, 5 mins later the oil levels are around 3/4 mark and then when checked again when the engine is hard cold its back to the max mark..

Not really. You're meant to check oil level hot after 5 minutes & fill it to the max mark. 5 Mins is plenty of time for oil to drain down.

Unless I'm talking sh*te??

This was the way with the Ford engines I used to dyno test on durability / performance test beds.

Guess I'd better go and read the Supe handbook?

I've never had a car which you check the engine oil level when hot!

It's got to be cold.

I've never had a car which you check the engine oil level when hot!

 

It's got to be cold.

Have to agree there, When cold all the oil has settled back into the sump allowing the dipstick to read correctly. When warm the oil level is always lower on the stick. This must be how some garages overfill the oil when servicing.

I'm not technical at all but in my service book it says to measure when at running temp!!!

I'm not technical at all but in my service book it says to measure when at running temp!!!

In the workshop manual it doesn't specify hot or cold.

I think the dipstick would have had hot and cold markers on it like the PAS if that was the case.

I've been talking crap again. Found lots of info in Google and it basically means you can check it hot or cold but there will be a difference in readings since oil expands with heat. Seems the best practice is to leave the engine stopped for 5 - 10min then check the oil.

http://www.halfords.com/webapp/wcs/stores/servlet/product_storeId_10001_catalogId_10651_productId_168020_langId_-1_p1_38270_p2_31276

Last time i filled mine to the full mark the front main seal went:(

Depends on the manufacturers recomendations. Most tend to set the oil level on a hot engine that's been left switched off for 10 minutes or so.

The main reason for this is when developing an engine they don't want to be paying for a dyno sat for hours waiting for the engine to go cold before checking / setting the oil level.

I know Land Rover used to run tests at under and overfill conditions (+/-0.5l I seem to remember) to try to protect against errors.

It certainly wouldn't worry me to be a couple of mm above max.

Oil - measure cold or at least ten minutes after use.

Auto box - hot and running.

2-3 mm is not an issue your seal will be fine unless you have another problem.

Depends on the manufacturers recomendations. Most tend to set the oil level on a hot engine that's been left switched off for 10 minutes or so.

The main reason for this is when developing an engine they don't want to be paying for a dyno sat for hours waiting for the engine to go cold before checking / setting the oil level.

I know Land Rover used to run tests at under and overfill conditions (+/-0.5l I seem to remember) to try to protect against errors.

 

It certainly wouldn't worry me to be a couple of mm above max.

You don't work for Lotus do you???

Every engine I've worked on the design & development of I have had oil levels set at hot 5 mins or so. Aston DB7, Jag XJ220, all Ford engines, Daewoo 2.0 gasoline, Volve D12 12 litre big bas*ard etc.

Whatever gave you that impression?

Just change the filter again as it should bring the oil level back down to a better level and only cost a fiver

I use a syringe and length of plastic pipe (marked to give the correct level) down the dipstick tube to set the level in the auto box. This lets you fine tune the level whilst the engine is still running. Saves having to go underneath the car and repeated removal of the drain plug.

Not tried this with the engine oil level yet though.