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Overfilled oil - Blue smoke

7036 Views 4 Replies 4 Participants Last post by  ElmerFud
Hi all

Checked the engine oil today and there was nothing on the dipstick!... must be losing oil when moving. Paniced and overfilled it up with 5lt of Halfrauds 5w40 and got blue smoke on the way home while overtaking (thought it was 5lt for the engine).

Had a 15 mins run back home. Left it to cool. Oil was at F on stick, no water in oil or vice versa.

Is it possible that there was more oil in the engine than the dipstick was showing?

Haven't changed the engines yet so this is still the 160,000 miles one. Have I blown a gasket? Engine sound fine and power still there. Is it happening because of the extra oil pressure or something? Only get the blue smoke on medium to high rev range.

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Chances are with that mileage you have worn valve guides and the top up is being burnt in the cylinder because of the added pressure.

You would notice it more on start up from cold and when backing off the throttle tbh. When you're not on the throttle you're not burning fuel so the oil would get burnt and be more visible.

Try getting someone to follow you to see when it happens as you can always tell when driving.

If you'd blown a gasket you'd either get white smoke from water being burnt in the cylinder (steam) and a rapid loss of water or a lack of compression in a cylinder which would run lumpy and not make power so I doubt if its that.
In a word.... (or two)

Ask Storm !

Sorry G.. couldn't resist the temptation..

Seriously though, overfilling can cause oil to go up the breather pipes and in through the manifold and get burnt.. also the excess pressure can force the oil to get past worn seals causing leaks, or into the combustion chamber..

the advice is to check the oil level from cold, and drain some out if needed..

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And right on cue..................

I had a similar experience a long time ago,not long after I'd bought the car - noticed that the dipstick was showing zero, so bought 5l oil and kept topping up.

Car was running lumpy and, at one point,when I dropped the hammer on her, all I got was a pile of blue smoke out the back.

Took it to my local mechanic who did the examination - someone had put the wrong dipstick in the car. When he drained it, it actually had 11.5l of oil in it - yes 11.5litres!!!!!!!!

That's an engine that "takes a lickin' and keeps on tickin'"


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thx guys.

Hi G. When I saw the blue smoke coming out of the back I thought the engine was toast!

Had the oil drained until the stick was at F. Looked about 3 litres in the bucket though. No more blue smoke.

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