Burning Oil When Hot

mrmupton

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I'm using 20W40 from the oil change kit. I'll clean it out as see if it helps.
That E10 fuel does not have the octane to run properly, If your plug was gray in color this is a sign of a clean burning engine, clean up the engine with something so you can see where your leak is
The only place i saw build up was around the rod that goes into the engine below the carburetor. But would that cause the engine to not run well? I couldn’t tell if it was leaking there though. Is that the governor rod?
 

bertsmobile1

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OK
So it started to run bad after you ran out of fuel
This suggests a partially blocked fuel line.
This can either be crud in the lines or tank blocking the outlet or damaged fuel lines
Remove the fuel line between the pump & fuel tank ( the pump has check valves in it )
Blow back down the fuel lines .
If it is really hard to blow back and the engine then runs better that suggests fuel starvation from obstructed tank / lines
 

mrmupton

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OK
So it started to run bad after you ran out of fuel
This suggests a partially blocked fuel line.
This can either be crud in the lines or tank blocking the outlet or damaged fuel lines
Remove the fuel line between the pump & fuel tank ( the pump has check valves in it )
Blow back down the fuel lines .
If it is really hard to blow back and the engine then runs better that suggests fuel starvation from obstructed tank / lines
Thanks.. sounds like it could also be breather tube? I changed the fuel pump end of last season. It runs fine as long as it is not under load. The smoking + loss of power seems to suggest that? Never replaced breather assembly… sounds like a pain?
 

bertsmobile1

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The engine is running on the idle jet untill you turn the blades on
This is why the run speed ≈ 3600 rpm is often called "high idle "
When the blades get turned on the throttle open up and fuel is drawn through the main jet
So if the float bowl is only partially full or the fuel flow is compromised then engine faulters .
 

mrmupton

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Hi all, thanks for your continued help through this. So I found that one cylinder has a fouled spark plug that looks like it has wet oil on it. When I recently did an oil change both the plugs were fine looking. This is after running for an hour or so afterwards. The mower stopped I assumed because of fuel being out but when i refilled it had low power and wouldn’t cut. When I refilled i used E10 instead of ethanol free, but it had low power so I assumed I needed to switch to ethanol free. I did not run E10 very long (5 mins?). Do I have a leak in the cylinder now and need to get the rings head gasket and seals replaced or should i just replace the spark plug? I think the earlier smoking could have been from a leaking oil filter (not leaking now).
 

Bertrrr

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Install a new plug , if it's wet looking it's not firing - there's your power loss, The type of gas you used does not effect the rings / compression etc. It's just a lower octane and does not deliver the needed power for your machine.
I suffered through a tank of this by keeping the machine choked but do not fool with it anymore,
Pull both plugs and ground them while cranking over the machine , they should both show a spark if one does not, it's bad or the coil wire attached is not. Swap the plugs over and retry to prove it's the plug or wire attached.
 

bertsmobile1

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Different energy contents is why carbs have replaceable jets
When we went from leaded to unleaded jet sizes went up 11 % ( on average ).
When e-10 was announced jet sizes went up 4% to account for it's lower energy content ( on average )
 
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