Smoke upon starting

Rls8836

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2006 ExMark 19 hp Kawasaki. I know it’s old but, I guess the valve guides are worn or does this mower have valve guide seals like the cars I used to work on. It usually smokes upon start up until it clears the combustion chambers of oil leaked by the valve guides, then it smokes no more and really uses hardly any oil all season long. I’m just a homeowner and it’s not used professionally. Can you just buy valve guide seals and put it back together and alleviate the majority of the white smoke. It’s kinda white to gray smoke but smells oily. OR, can you buy valve guides and seals and still reuse the original valves? Is this something I can do at home or is it a job for a mower shop to replace the guides. Thanks
 

bertsmobile1

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When was the last time you cleaned the cooling fins
Smoke on start up that clears is one tell tale of overheating
That causes the oil to thin down too much and pool inside the cylinder as the engine cools down .
 

Born2Mow

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Smoke on startup could be an indicator of many things.... (in no particular order)
• Engine oil over-filled.
• Fuel diluting the engine oil.
• Wrong grade (weight) or type of oil. Generally, automotive oils sold at Walmart are not good in air-cooled mower engines.
• Advanced engine wear from missing regular oil and filter changes. (This is especially true if you buy a used commercial mower.) Fresh oil is the cheapest insurance you can buy. Change your engine oil AT LEAST once a year.
• Clogged air filter causes the intake to pull more "air" in through the engine breather.

And this list is by no mean complete.
 
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Rivets

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What color is the smoke?
Black=rich running condition
Blue=oil
White=water or fuel mixed with oil
 

Tiger Small Engine

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What color is the smoke?
Black=rich running condition
Blue=oil
White=water or fuel mixed with oil
How many hours on mower? It is doubtful that simply replacing valve guide seals will stop the smoke upon start up. It is common for small engines to have a puff of smoke on start up. How much and what color smoke on start up?
 

StarTech

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Yes most Kawasaki has valve stem seals and they do go bad from wear. But they can be damage from valve guide moving out too.

As Tiger said it is common for Kawasaki and Kohler engine to smoke a little when they start up, Even brand engine from these two OEM smoke at start up. But in this case being 9 yrs old it is probably time for new seals at least. And you will need a few more gaskets too when you remove the head(s).[don't which Kawasaki engine so it can either a single or v twin. And I have replaced a few bad head gaskets too.
 

sgkent

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I have a Toro personal pace mower that smoked light white-grey smoke when it started every time since it was new. Just that initial small cloud. About six months ago I moved from the ethanol laced fuels here in California to TruFuel. It has not thrown up that initial puff of smoke since then. No idea why the fuel would change that, but it did. It also starts on the first pull whereas it used to take three or four pulls.
 
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