Effects of engine overfill

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You have some questions today don't you? One quart you probably will not notice a thing. If you over fill you sump too much you start to have a problem of your engine seals bursting off the engine because of too much pressure but I have never seen that I just read about it.
 
Depending on the design of the oil pan you could also get frothing as the crankshaft skims the top of the oil.
 
Sluggish performance would be the least of your worries. If its overfilled and contacts the piston rods, its will cause the oil to foam , and where theres air, theres no lubrication.

Every motor is different, I wouldnt risk it. Drain it or at least get a syphon pump.
 
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Yes I do have a lot to ask! One time my engine was shaking so much, i had new plugs oe, i think the stupid mecanic overfilled by one quart, and i think its too much for a 1.6L.
 
The worst thing I've actually seen is foaming the oil. But I've poured a quart of MMO on top of an already full sump, and when I drained the oil about 500 miles later, there was no foam.
 
On a 2nd gen Prius, 1/4 qt will likely result in reduced fuel economy and oil pooled in the throttle body.

Larger amounts of overfill supposedly, according to a TSB, will result in a no-start.
 
Originally Posted By: penz08
The max is 3.3L


I wouldn't worry, I've overfilled mine by a quart and just let it burn off with no ill effect or blown seals.
 
Originally Posted By: The Critic
On a 2nd gen Prius, 1/4 qt will likely result in reduced fuel economy and oil pooled in the throttle body.

Larger amounts of overfill supposedly, according to a TSB, will result in a no-start.
wow, is it that bad? My car got a 1.6L , economical on gas, is smaller engine are more sensitive to overfill?
 
I know a place that opened one drain plug on a 996 and not the other one, and then poured 10 liters of oil in it. It was smoking and leaking from a seal.
 
It depends on exact engine design. On the roadcourse 2.0L DOHC Neon routinely ran 1 Qt Low to reduce the number of spun bearings caused by aeration of oil that occurred when the crank contacted oil. On the other hand Corvette LS1's routinely ran 1 qt overfilled to reduce the chance of uncovering the pickup in High-G, High-RPM Sweepers.
 
Originally Posted By: silverrat
I know a place that opened one drain plug on a 996 and not the other one, and then poured 10 liters of oil in it. It was smoking and leaking from a seal.


Ouch, I would probably shed a tear if that was my 996...
 
Originally Posted By: Brenden
Originally Posted By: silverrat
I know a place that opened one drain plug on a 996 and not the other one, and then poured 10 liters of oil in it. It was smoking and leaking from a seal.


Ouch, I would probably shed a tear if that was my 996...
Then immediately after I leave the premises, I'd be going in my head, "yes! I get a new engine!" lol......paid in full :p

Due to stupidity.....hehe.

Was at WM today getting tires balanced, dude was working on a newer model Kia or Hyundai......with the top end cartridge filter jobbys, drained the pan not realizing Walmart did not carry the filter.....well the dude got free oil anyways, just no filter :p They didn't charge him either......he only had 5k on the clock he said. hehe.
 
Originally Posted By: dave1251
You have some questions today don't you? One quart you probably will not notice a thing. If you over fill you sump too much you start to have a problem of your engine seals bursting off the engine because of too much pressure but I have never seen that I just read about it.


Isn't the oil pressure regulated by a bypass valve? It shouldn't get any higher than normal. In fact, the oil pressure may experience a drop occasionally if the oil gets all frothy and whipped up, causing partial and very temporary 'scavenging'. However, overfilling can cause the crank to splash the sump.
 
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