overfilled the DODGE 2003 GRAND CARAVAN during oil change

I'd go ahead and remove a quart. Having the level too high puts it in greater contact with the spinning crankshaft and it get splattered around a lot more inside the engine. It might be fine, but there are some problems that can result from that.

Or possibly create Hydraulic Lock if the oil pressures itself past the seals...

If you replaced the filter, but have not started the engine yet, you may be seeing the filter volume (which will go away when you start the engine).

Otherwise, if you have really overfilled it, then drain out a quart or so.

You can tolerate a little overfill with no problem, but a quart or more is too much.

????????

Would you please explain the technology supporting this statement?

Are you sure you put in too much oil? I had a Dakota that took 6 qts in the 4.7 V-8. I was the first person to change the oil and the dip stick showed that it was over full. I was positive I only put in 6 qts. with the filter. I found out the Dakota had the wrong dip stick. I never found the correct dip stick, so I just filed a notch where the FULL level was.

Hank

Oil is under pressure. If there is too much oil, and the pressure builds, then it can push out seals meant to keep it out of places. If the OP is luck, it will push a seal out at one end of the engine or another and leak onto the ground or into the tranny (depending on your definition of "luck")

If not, it can push out the valve seals and drop into the engine, and since a liquid cannot be pressurized...BANG! Hydraulic Lock...

...

Er....

.....exactly what engine are you talking about that has pressurized oil against the valve seals?

Any oil that manages to bypass the valve seals usually ends up burned - creating that familiar blue smoke.

There is nothing accurate in this post... The oil pump is sucking oil out of the oil pan which is essentially a bucket. The oil pump has no idea if there is 1 quart of oil in that bucket or 300 gallons of oil in that bucket. The problem with overfilling is that the spinning crankshaft comes in contact with the oil. The whipping action of the crankshaft will aerate the oil and turn it in to a foamy froth. The oil pump can not pump this froth so you loose oil pressure and soon after loose an engine if you don't stop.

Valve seals are not exposed to pressurized oil. Any lubrication needs they have are handled by oil splashing off the other valve train components.

Steve B.

You are correct Steve. Also, don't the oil pump have a pressure relief valve built into them so that excess pressure doesn't build up?

Hank

Hank

Oh wow that's quite the story. Liquids can't be compressed eh? Well damn, that's just re-writing the laws of physics right there. I guess oil doesn't burn in the combustion chamber either. You learn something new every day.

While he's wrong about the oil "locking up" the engine, it is indeed true that liquids can't be compressed. You can put pressure on a liquid, but you can't compress it. There's a difference. That's the fundamental principle of how hydraulic systems work...

Perhaps you should have paid more attention in that high school physics class...

It's easy to get a hydrostatic lock with glycol/water...all it takes is a head gasket leak.

SBlackfoot wrote in article ...

As wrong as he is about everything else, Pascal's Law - and virtually everything hydraulic - works on the very principal that liquids, in fact, CANNOT be compressed.

They can be pressurized, but NOT compressed.

OTOH - You are correct in chiding him about oil burning off in the combustion process.

He is? How? You guys keep telling me I'm wrong, but did you ever have it happen to you?

The one time I went ti Jiffy Lube, they overfilled by 3 quarts. The car started hard and the engine blew. They wanted to put in a 'remanufactured' engine, but the car was a year and a half old, so I insisted on a new engine.

Oil can't lock up an engine, huh? Sure...

'88 Honda Accord. JiffyLube overfilled it by three quarts. I don't know how it happened, I know they gave me a new engine...I'm just going by what the Honda Service Manager told me. I figured he knows what he's talking about...

The oil sitting in the pan is not under pressure (under normal conditions in most engines, I am sure if I didn't write this someone would find a some engine made in east germany in 1961 that was in 45 cars that had the oil in the pan pressurized and call me a dumbass for not considering it). The oil in the passages is. The pump picks up the oil and it is pumped through the system then returns to the pan. The oil pressure builds against the resistance of pushing the oil through the small passages, bearings, etc.

When an engine is over filled with oil, the oil pressure doesn't increase, the crank dips into the oil in the pan splashing it around. The oil get frothy with air and then these air bubbles are in the oil as the pump picks it up and circulates it. Of course air doesn't do a good job lubricating internal engine parts and the engine fails.

Nope. See below.

Perhaps it can (I won't claim to know all possible situations), but not in the manner you claimed ("leaking past the valve seals").

Is that clear enough for you?

Well, I guess IF the crankcase was just SO full of extra oil that there was absolujtely no room for the downgoing pistons to move it, then some degree of hydraulic locking MIGHT be possible. In that case, blown crank seals MIGHT be a possibility.

Hydraulic locking is usually associated with a full combustion chamber, either with fuel or with coolant or, in the case of radial engines, with oil in the bottom jug.