black smoke

[FSHKPR]

Hello I have a Murray riding lawn mower that idles fine but when ever i put a load on it. engage the blades or even just drive it. it puffs black smoke. seems to run good even with a load just the black smoke. what causes this? Rings bad? carburetor problem?

 

[JB]

Re: black smoke

Burning oil.

Several ways the oil can be getting into the cylinder(s). Poor sealing rings (compression check), worn valve guides are the most common, but there may be more.

 

[gss036]

Re: black smoke

I was always under the impression that black smoke was fuel related and blue smoke was oil related. I am not a small engine mechanic by any means but have done a lot of tinkering over the years. Check to make sure the gasket between the carb and the engine is OK and bolts/nuts are tight. Most small engines have a fly ball type governor on them and if not properly set will cause surging, a bad carb gasket will do the same thing.

 

[v1_0]

Re: black smoke

Hello I have a Murray riding lawn mower that idles fine but when ever i put a load on it. engage the blades or even just drive it. it puffs black smoke. seems to run good even with a load just the black smoke. what causes this? Rings bad? carburetor problem?

Blackish smoke usually = carbon = unburnt fuel = rich mixture. Check your sparkplugs, see how fouled they are.

Blueish smoke usually = oil = oil leak/oil in fuel.

Whitish smoke usually = water = water leak, but you don't have liquid cooling so not to worry. Also, this is *after* a engine has warmed up - one of the byproducts of burning gas is water. When you shut your engine down it cools and the water condenses - also dew forms overnight. As your engine/exhaust heats up this will steam off - that is normal.

Again, I'd say take a look at your plugs. http://www.gnttype.org/techarea/engine/plugs.html

 

[dlngr]

Re: black smoke

It's running rich. First thing to do is replace the air filter.

 

[JB]

Re: black smoke

Yeah. Don't know what I was thinking. Guess my memory is going.

Also, I think my memory is going.

 

[JustJason]

Re: black smoke

Hey JB.... i think your memory is going