My Mountfield lawnmower is blowing out thick blue smoke!

[Rachelbehart]

My Mountfield lawnmower is blowing out blue smoke - what has happened to it?

I have checked the oil level and topped it up and have also refuelled with petrol - although not sure what kind. Have taken on board other comments to the availability of leaded fuel nowadays so dont think I would have bought Leaded fuel! Though I may have had a blond moment! Ha!

It is spurting out black oily substance out of the exhaust and over the manifold - so surely it may be that getting hot and burning. Is it dangerous to use? Is it broken? I have only mowed half my lawn!!!!!

 

[oilman]

If it runs, it will run just as well on unleaded fuel. It could have a broken piston ring, or a seal round the exhaust valve has failed. A repair is possible, but AFAIK when this happens nowadays, a new engine or new mower is cheaper. You can get a second hand mower where someone has replaced theirs and traded the old one in. Or there's freecycle turns up some gems.



How big is your lawn?

 

[Thermo]

look out the old grim reapers about to get his mower out!

 

[jono_h]

Could it have been accidentally filled up with a 2-stroke mix? Some engines (2 stroke) run on a petrol and oil mixture, which if used in a 4 stroke engine could cause it to run smokey.

 

[r896neo]

Leaded petrol would do it no harm at all, it had been discontinued because it destroys catalytic converters which i'd be pretty confident your old mountfield does not have. Its obviously burning oil and its probably as oilman said a valve seal problem or a ring. either of which will not be econoically worthwhile to fix unless you do it yourself.

Sorry.

 

[goodmow]

I think you might be asking the wrong questions.
Has this engine been over filled with oil?
Has the lawnmower been turned on its side to clean?
Has it ever been serviced because the carburettor diaphragm and air filter need to be changed on a yearly basis.

 

[oilman]

Has it ever been serviced because the carburettor diaphragm and air filter need to be changed on a yearly basis.

In that case most mowers are waaaaaaayyyyy past their service date.

 

[goodmow]

Yes they are and that is why so many people end up throwing their lawnmower away and buying a new one when a repair or service would be a much cheaper option.

 

[oilman]

But they don't care about cost, they want a new one.

 

[Bodgeit and scarper ltd]

the best thing to do with a Mountfield lawnmower it to throw it away. the old ones were ok, but the newer ones are rubbish

 

[mattylad]

Dont throw it away, put it on your local Freecycle/Realcycle site.

Someone may be prepared to strip it down & repair it themselves.