F725 big white smoke cloud

Bama66

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Just serviced my engine oil & filter, transmission fluid and filters, air and fuel filters. While mowing a huge cloud of white smoke came out of the exhaust while I simultaneously noticed a brief decrease in engine speed. Lasted about 2 seconds. i immediately killed it and checked all fluid levels and looked for any leaks. All was fine. I started mowing again and this occured twice more before I shut down for the day. Any ideas what’s going on? TIA!
Johm
 

7394

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Does the engine oil smell like gas ?
 

7394

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Gas is probably passing thru the carb into the crankcase. Do you have a fuel line shut off valve ?

If gas is getting into your crankcase, you need to fix the problem, Carb needle valve maybe. & then dump the oil,
add cheap fresh oil run it a bit & drain it again, then add the regular oil you use,.
 

platefire

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I don't know if you have completely confirmed you do have gas in your oil?
Regarding the smoke bomb effect, I have had that happen when I started
mowing and my oil cap was loose.

I also have had gas in my oil when I filled my gas tank extra full
and somehow my carburetor float valve failed and gas migrated into the crank case.
If that's the case, as Lawn Addict says, you got to get all that old fuel/oil mixture out and
get the good new oil in
 

Bama66

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Gas is probably passing thru the carb into the crankcase. Do you have a fuel line shut off valve ?

If gas is getting into your crankcase, you need to fix the problem, Carb needle valve maybe. & then dump the oil,
add cheap fresh oil run it a bit & drain it again, then add the regular oil you use,.
There is a fuel cutoff. I have never used it.
 

7394

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I'd try & determine for sure you has gas in your oil first. Is your oil lever ever fuller that is was ?

I use my shut off on my mower. Had an old rider long ago & it hydro-locked from gas in the oil.
 

Bama66

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I’ve got bowl off carb.and flipper float up and down a few times.
I don’t think I’ve done anything to fix problem. What do you suggest I do next before changing oil?
TIA
 

7394

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Well, an inspection of the needle valve above the float would be good to see that it is clean.
If you have gravity feed gas, put a can under carb with bowl off, allow gas to flow, gently push the float closed upward (carefully)....I say carefully cause the float level is set by that tab, & pushing too hard can really mess up the float level..

Fuel should stop asap, then...
 
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