Over filled oil

3 replies to this topic
  • Ranger_426F

Posted June 25, 2002 - 03:49 AM


Question for the board,

Just wanted to know what could or can be damaged by overfilling the oil level. I ask this because I have overfilled twice and had to drain it back down to the correct level on the dip stick.

With cars I guess you can float the valves and put extra pressure on your guides, and the crank will virtualy spin in a vat of oil.

But the 426 can only get so much oil to the pump and system. The only thing I can think of is that if it is filled over the return oil line that oil could flow back down the tube or that the oil has to be pumped into a liquid instead of the hollow frame.

I'm not talking about puting 2.5 quarts in the thing. Just over the top mark on the dip stick.

Your thoughts.

[ June 25, 2002: Message edited by: Ranger_426F ]

  • vznx1w

Posted June 25, 2002 - 04:08 AM



Don't worry. On cars and bike with wet-sumps, overfilling raises the oil level closer to the crankshaft, increasing the air/foam that is whipped into the oil. The energy taken from the crank is also converted to heat, raising the oil temp.

However, in a dry-sump neither of these happens as the scavange pump keeps the oil out of the engine--assuming that there's room for the extra oil in the tank/frame. In your case (just mildly overfilled/still room in the tank) the engine won't know the difference.

Ride On!

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  • Fastest1

Posted June 26, 2002 - 09:15 PM


Too technical. The motor will blow it out the breather as soon as you rev it during riding. Nothing to worry about. :)

  • dezthumper

Posted June 26, 2002 - 05:41 PM


Just over the top line is where I fill it each time because it blows out the excess anyway. I never had a probelm on my 98,99,00,01 or 02 doing this. I hope the same holds true for the 03.

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