Put to much oil in car....

My ex seized the engine on her motorbike (125 marauder) by not putting any oil in it - so when she got a car and noticed the oil was below the maximum mark on the dip-stick, she decided to put almost 5 litres of oil into it :eek:

her: I noticed the oil was low, so I filled it up.
me: how much did you put in?
her: (holds up 5L oil can) oh, I don't know... I just poured until the bottle was empty.
me: what?!
her: what do you mean 'what?!'
me: didn't you check the level as you poured, or look at the manual to see how much oil the car is supposed to have in the sump or better yet ask me to do it?
her: (indignant) no, why should I have? I can do things for myself you know...

Talk about having your thumb up your arse and your mind in neutral :rolleyes:
I should have just let her drive it to work and take the responsibility for it breaking down and having to be towed to a garage.

Too much oil is as bad as not having enough. A small over-fill like (eg 250ml) probably won't do much harm, if any. But virtually doubling or tripling the amount of oil in an engine is a good way to kill it.
 
its definatly not blue smoke at the back just more white thicker smoke tbh.

But it seems to go thin and sometimes more....

perhaps im just worrying about nothing and the noise/extra smokes is just due to the snow/chilly weather we been having:)
 
I overfilled my Mondeo by mis-reading the dipstick same as the OP, I over-filled it to the point that it started to come out of the fill hole and was spilling into the engine !!
It was on the morning of a 600mile round trip to Gt Yarmouth and back, I had the rattling exhaust same as the OP but didn't notice any excess smoke, apart from that the car was fine all the way up.
It was only on the return trip I ran into problems, the car was hard to start, and I lost all engine power on about 3 or 4 different occasions, which was rather disconcerting on a packed M25 with no hard shoulder.
It got us home eventually and i've had no problems since, which is about 2 months ago.
 
HighlandeR said:
perhaps im just worrying about nothing and the noise/extra smokes is just due to the snow/chilly weather we been having:)
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You are worrying about nothing! Even if it was on max the amount you are talking about wouldn't have caused any issues. The white "smoke" is just condensation burning off, this is often inconsistent as it does so and finally many engines are noisier in these really cold conditions until they are warm.
 
dipstickoillevel.jpg
 
Matt82 said:
supplying the feed is creating the pressure, innit?? lol
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No, the pump gets the oil to the crank, the crank bearings create the high pressure oil supply

From my bosch technical manuals introduction-


'The oil pump itself never creates pressure, the pressure is produced by the resistance in the engine block, more specifically the clearance between the bearings and crankshaft journals'
 
dalin80 said:
No, the pump gets the oil to the crank, the crank bearings create the high pressure oil supply

From my bosch technical manuals introduction-


'The oil pump itself never creates pressure, the pressure is produced by the resistance in the engine block, more specifically the clearance between the bearings and crankshaft journals'
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That's an over-simplification, you need something to generate the flow of oil (the pump) and something to resist the flow (bearing clearances) to create pressure (within the oil galleries). The pressure in the bearing is created hydrodynamically by the rotation and is much higher than the pressure in the oil galleries, but still relies on the flow of oil from the pump.
 
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Dogbreath said:
That's an over-simplification, you need something to generate the flow of oil (the pump) and something to resist the flow (bearing clearances) to create pressure (within the oil galleries). The pressure in the bearing is created hydrodynamically by the rotation and is much higher than the pressure in the oil galleries, but still relies on the flow of oil from the pump.
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no no no. just pour some oil on the bearings and the oil will "pressure"

:rolleyes:
 
Dogbreath said:
That's an over-simplification, you need something to generate the flow of oil (the pump) and something to resist the flow (bearing clearances) to create pressure (within the oil galleries). The pressure in the bearing is created hydrodynamically by the rotation and is much higher than the pressure in the oil galleries, but still relies on the flow of oil from the pump.
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No, the over simplification is saying the pump creates pressure.

Pressure is restriction to flow, the pump only creates flow.
 
Dogbreath said:
That's an over-simplification, you need something to generate the flow of oil (the pump) and something to resist the flow (bearing clearances) to create pressure (within the oil galleries). The pressure in the bearing is created hydrodynamically by the rotation and is much higher than the pressure in the oil galleries, but still relies on the flow of oil from the pump.
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Yeah, the pump only creates the flow of oil, it's the resistance that creates the pressure, and the two, as you say, are related.

It's like putting your hand over the end of a hosepipe. The pressure increases as the diametre of the hole at the end of the hosepipe is reduced (beacause this introduces resistance to flow). However, if you adjusted the flow rate up or down, the pressure would likewise fluctuate (assuming the restriction remains constant).

Oil pressure in an engine is like that. The pump produces a specific flow of oil at a specific RPM, which is then pressurised by the restrictions in the oilways. If the bearings wear so those restrictions become less, then the pressure will drop, assuming the pump flow rate remains constant. Alternatively the pump could wear, thus reducing flow, which will likewise cause a similar drop of pressure.

As revs rise, the oil pump flow rate would increase, and the pressure would rise in relation. The pressure release spring affects the rising rate of pressure by opening a new oilway (back into the sump, or wherever) which, in turn, causes a reduction in the restriction and a subsequent reduction in pressure (in order to keep maximum pressure stable as revs rise).

This is often a problem in the cerb engine. The release spring loses it's strength and the ball bearing at the end stops sealing the return oilway properly, thus causing a reduction in the engine restrictions and a subsequent drop in oil pressure... this leads to wear in the bearings, which erodes the tolerances, thus reducing the pressure even more and so on, until the bottom end needs a rebuild.

At least, this is how I understand it all to work... :)
 
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