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Never Late
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everyone says to much oil is worse then running a little low on oil....why is a little to much oil not good?
 

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"a little" too much oil is not a bad thing - it's when you have so much in the engine that the crank starts hitting the surface of the oil in the pan while rotating that you can start wreaking havoc. You can imagine the speed at which a crank is moving - hitting the surface of a liquid at that speed is going to really mess up the rotation and balance and speed... basically risk rattling the engine apart.

At least, that's how I understand it.
 

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Color me Gone
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nval8 said:
everyone says to much oil is worse then running a little low on oil....why is a little to much oil not good?
Take your hand and swing it through the air, now go to the tub and run it full of water and then swing your hand through it. Thats the effect of the motor running with oil hitting the crankshaft. Over the years I have seen several engines come in running terrible with too much oil in them. Some to the point they were pushing oil out all the seals. However I have never seen it do any long term damage. Every time I have been able to drain out the excess and all returns to normal. The engines have no power at all though because of the slapping the oil that takes place with the crankshaft, many won't even idle right with them overfull. I don't consider it nearly as bad as running an engine low on oil though.
 

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I thought it was an issue of beating the oil to a froth, getting air into it, and then the oil not lubing right and focking up your engine. :confused:
Where's Ken?
Isn't that why they use non-detergent oil in air compressors?
 

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Pondo said:
I thought it was an issue of beating the oil to a froth, getting air into it, and then the oil not lubing right and focking up your engine. :confused:
Where's Ken?
I'm with you and Max on this one...
 

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Color me Gone
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Pondo said:
I thought it was an issue of beating the oil to a froth, getting air into it, and then the oil not lubing right and focking up your engine. :confused:
Where's Ken?
Your right it will foam, and thats why it pushes it out the seals from pressure. Usually when they have oil hitting the crank they won't run fast enough or hard enough though to get the power to damage them from the foaming of the oil, or I will say I haven't seen them. They run so bad you have to know there is something terrible wrong with them right away.
 

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In my experience, froth was always a case of coolant getting into the oil (bad head gaskets).

I've driven a lot of beaters right into the ground through the years... :)
 

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As a ICML certified machinery lubricant analyst (worked as a maintenance engineer for a few years) I can tell you that the main thing you're worried about is in fact foaming of the oil. Yes, there are anti-foaming additives in the oil but if you excessively overfill and create a foaming condition you will have metal-metal contact.

Of course, the pressure created in the base can possibly (depending on design) blow seals, pump oil into the breather tube possibly washing into your filter or down the intake etc. But it is the foaming that matters most.
 

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Color me Gone
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jlavallee said:
As a ICML certified machinery lubricant analyst (worked as a maintenance engineer for a few years) I can tell you that the main thing you're worried about is in fact foaming of the oil. Yes, there are anti-foaming additives in the oil but if you excessively overfill and create a foaming condition you will have metal-metal contact.

Of course, the pressure created in the base can possibly (depending on design) blow seals, pump oil into the breather tube possibly washing into your filter or down the intake etc. But it is the foaming that matters most.
Have you ever driven a car or ridden a bike that the oil is hitting the crankshaft? If just driving the oil pump takes 7hp in a v-rod can you imagine how much hp you give up when the crank hits solid oil every time it passes? :)
 

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Color me Gone
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Steppenwolf said:
really?! Holy crap - I had no idea it was that much.
I heard through the grapevine that some one might be working on a new pump that has the same pressure but uses only 4hp. :) But you know how rumors are.

Yes water pumps, oil pumps and other things inside the engine use a great deal of the power. You can imagine the crank hitting solid oil and how that effects it. The first time I got an engine over filled with oil it had me stumped for over an hour. The would idle alright, maybe a little rough but wouldn't run over 2000 rpm and would start to vibrate something terrible. Give it full throttle and it felt like the exhaust was stopped up. Now you might get foaming that hurts if the crank barely touches but if you get one way over full I don't know you could get it up fast enough to ever do the damage because it simply won't run that fast with the crank hitting oil.
 

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Steppenwolf said:
really?! Holy crap - I had no idea it was that much.

Just imagine that a Top-Fuel dragster uses 900hp to turn its supercharger. :notworth:

My opinion is all of the above.

1. Crank hitting the oil causes foaming which extremely decreases the oils ability to do its job.

2. Crank hitting the oil causes the engine to run very rough and poorly.

3. Off topic, Coolant will also cause foaming of the oil.
 
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