Oily Spark Plug

tom3

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If the cylinder has any serious wear and scoring, you'll see it with the piston down in the hole.
 

Shorter Grass

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The engine has sat overnight with the head off and today a pool of oil is in the bottom of the horizontal cylinder which can only be piston, piston rings or cylinder.

Will it be enough to just replace the piston rings?
 

Scrubcadet10

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I cant imagine oil getting to the cylinder with it just sitting. and the head off ...How much oil are you putting in it?
The engine holds approximately 5/8 qt (20 ozs; 0.6 liter).
 

Richie F

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The bore of mine has not been honed from the factory so there is no cross hatching?
That is impossible. All engines are honed from the factory.
That's how the rings seat into the cylinder bore.
If you have no cross hatch, your engine has wear.
Using oil, using more gas to run, harder to start, fouling spark plugs and oil smoke (which is blue in color not white).
 

Shorter Grass

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That is impossible. All engines are honed from the factory.
That's how the rings seat into the cylinder bore.
If you have no cross hatch, your engine has wear.
Using oil, using more gas to run, harder to start, fouling spark plugs and oil smoke (which is blue in color not white).

Could I re-hone the cylinder and fit slightly oversize piston rings that can be bought?
 

Shorter Grass

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I cant imagine oil getting to the cylinder with it just sitting. and the head off ...How much oil are you putting in it?
The engine holds approximately 5/8 qt (20 ozs; 0.6 liter).

The oil was drained from the engine before I took the head off. Oil has seeped past the cylinder as it sat.
 

Hammermechanicman

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Oil seeping past bad rings is not uncommon. You have a couple choices. Get an oversive poston an rings and have a machine shop bore and fit new piston. Will cost more than the mower is worth probably. Or you get a set of standard rings and get a Brush Research ball hone appropriate to your cylinder material and deglaze the cylinder put new rings on original piston and put it together .
 

Shorter Grass

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Oil seeping past bad rings is not uncommon. You have a couple choices. Get an oversive poston an rings and have a machine shop bore and fit new piston. Will cost more than the mower is worth probably. Or you get a set of standard rings and get a Brush Research ball hone appropriate to your cylinder material and deglaze the cylinder put new rings on original piston and put it together .

I think I will use a honing kit and then fit new piston rings
 
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