Lawnmower spark plug black hard to start

Hi,
I'm just trying to fix up my mum's lawnmower - its a Honda "Buffalo" model. Fairly new - but she's hardly used it.
She had problems with it ever since she got it - but only now has she asked me to help - and the 1 year warranty has expired. lol.
It takes awhile to startup - a lot of pulls - but when it does it keeps on going.
I checked the spark plug - the top end is black with soot. The air filter seems fairly clean.
What's exactly the problem with it?
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On Mon, 21 Jul 2008 17:16:31 +1000,when reading "rec.gardens", I'm
saying:

Seeing it "WILL" run there doesn't seem to be much wrong with it. I assume it is a 4 stroke mower?

A black sooty spark plug could indicate a fuel or mixture problem, I like to see spark plugs a nice light gray colour.
First off empty out all the fuel in the tank and replace with clean fresh fuel.
Perhaps try to start it then or even better if you also replace the spark plug making sure you are using the correct spark plug for your Mum's Honda lawn mower.
--

Erik.


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Doesn't the spark plug gap need to be checked?
--

Billy
Bush and Pelosi Behind Bars
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3 things cause a fouled plug due to incomplete burning of the gasoline. One is too much gas, or running rich. Second, not enough air due to a clogged filter or other air inhibition, also running rich. Third, poor spark performance, usually a fouled plug due to one or both of the other conditions. Solved by simply replacing the the plug with a new one that's properly gapped. A new coil pack may be required if failing or weak.
--
Dave

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"YMC" wrote:

Mowers should become easier to start with age/use.
If it runs but hard starting, especially at the start of mowing season, 99.9 percent of the time it needs fresh gas... the plug is fouled from excessive flooding due to excessive attempts at starting. Pour out and dispose of all the old gas and fill with fresh. Do not buy more gas than can be consumed within two months... if there's surplus at the end of mowing season pour it into your automobile and run the lawnmower dry before storage... at start of mowing season buy fresh. Do not store gas over winter... and gas stabilizing additives don't really work very well nor are they cost effective for small quantities of fuel. If after filling with fresh gas starting is still difficult then you're not using the correct starting procedure, read the manual, paying special attention to priming and and use of the choke... if it takes more than two attempts to start a lawnmower but it finally starts and runs then it's not the mower, you're doing something wrong. It's a good idea to drain and change the engine oil at least once each year too... follow the manual recommendations for all maintenence; lube, sharpening, cleaning. Also make sure a mower is on a level clean surface before attempting to start, best to start a cold engine on a paved surface, and be sure the underside of the deck is clean, an obstructed blade will make starting very difficult, often impossible. Be aware that when people become frustrated with starting a mower is invaribly when accidents occur... look down and observe that your toes are not under the mower deck. Many people never even look at the underside of their mower... it should be scraped clean often... always disconnect the spark plug wire before working under a mower.
If you're not mechanically inclined (and I suspect you're not) I strongly recommend you have that mower serviced professionally at least once a year... Honda mowers are rather costly anyway (I suspect that mower cost well over $500) so by comparison it's not really so expensve to spend $50-$75 for a full service; new filter, new muffler, new plug, new blade, fresh engine oil. lube wheels and all moving parts, power wash under deck, test run and adjust... it might cost more to do it yourself, in fact I know it will.
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g'day ymc,
sounds like fuel mixture problem, can be caused by out of tune carby (probably highly unlikely on a relatively new machine), or the choke isn't opening after the mower starts this will starve the mixture of air and cause rich running so much so the machine is likely to stop in a short time.
and the other some filter elements can be installed incorrectly and cause the shut off of air flow.
if all else fails take it to the mower shop i'm sure it will be only a very minor adjustment that they will rectify quickly.
On Mon, 21 Jul 2008 17:16:31 +1000, "YMC"
snipped With peace and brightest of blessings,
len & bev
-- "Be Content With What You Have And May You Find Serenity and Tranquillity In A World That You May Not Understand."
http://www.lensgarden.com.au /
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