Why does my lawnmower blow white smoke?

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farmerjohn1324

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I just put a whole bottle of oil in. It blew white smoke both before and after the addition of oil.
 
What kind of oil and where did you put it?

White smoke is normally water vapor and blue smoke is oil. You don’t have any water in your engine unless your gas had water in it. Was it out of oil or did you drain the oil and refill it?
 
What kind of oil and where did you put it?

White smoke is normally water vapor and blue smoke is oil. You don’t have any water in your engine unless your gas had water in it. Was it out of oil or did you drain the oil and refill it?

It's 4 cycle engine oil. I put it in that part where the oil dipstick is.

For some reason, the dipstick is hard to read. Even after a whole bottle, it still seems like it's out when I look at the dipstick, but I can see oil when I look in the hole.
 
Make and model of your mower could help.
 
Well if you dumped a quart of oil in and didn’t drain any out, as in an oil change I would say your engine is burning a lot of oil and that is the smoke you see. These mowers are so inexpensive most of the time it doesn’t pay to fix them. Worn piston rings and valves will let crank case oil into the combustion chamber and it will be burned as fuel and will make blueish white smoke. All you can do is live with it for now and buy a new mower or if your deck is really good change the engine out. It will keep getting worse and if you don’t keep oil in it will get worse fast.

edit:

In thinking about it you could also be over full of oil if you don’t understand how to read the dip stick. When you say you can look down the hole and see oil is the oil close to the top or down around where the lines are on the dip stick?
 
Last edited:
Well if you dumped a quart of oil in and didn’t drain any out, as in an oil change I would say your engine is burning a lot of oil and that is the smoke you see. These mowers are so inexpensive most of the time it doesn’t pay to fix them. Worn piston rings and valves will let crank case oil into the combustion chamber and it will be burned as fuel and will make blueish white smoke. All you can do is live with it for now and buy a new mower or if your deck is really good change the engine out. It will keep getting worse and if you don’t keep oil in it will get worse fast.

edit:

In thinking about it you could also be over full of oil if you don’t understand how to read the dip stick. When you say you can look down the hole and see oil is the oil close to the top or down around where the lines are on the dip stick?

I'll just buy a new one.
 
The last time I refilled my lawnmower, after I drained the oil, it took 30 ounces of oil, leaving two ounces in the bottom of that quart of oil. IMHO that is a poor design and it makes it complicated and a waste of oil.
 
The last time I refilled my lawnmower, after I drained the oil, it took 30 ounces of oil, leaving two ounces in the bottom of that quart of oil. IMHO that is a poor design and it makes it complicated and a waste of oil.

Are you saying it's leaking oil? Where is the oil going?
 
Your rings are probably shot, and the oil is being burned off with the exhaust. You can pick up a Chinese knock off engine for less than $100 bucks, or just purchase a new mower for about $250 - $350
 
Find the modal number, look up the amount of oil it should take, change the oil with the correct amount, measure with a yellow pencil and record that for future reference.

Oil will burn down to the correct level or a little above but the spark plug will likely need to be cleaned a few times.
 
Find the modal number, look up the amount of oil it should take, change the oil with the correct amount, measure with a yellow pencil and record that for future reference.

Oil will burn down to the correct level or a little above but the spark plug will likely need to be cleaned a few times.

Where is the model number most likely located? Is what I posted up top not the model number?
 
My 25 year old Snapper ( Briggs & Stratton engine, 5HP) has been burning oil for a while. I just recently picked up an oil additive meant to stop oil leaks (Bardahl somethingorother) Too soon to know if it helps, but I will let you know.

Also make sure you are using SAE 30 oil. It is not the same as car stuff (not 10W30 etc.)
 
My 25 year old Snapper ( Briggs & Stratton engine, 5HP) has been burning oil for a while. I just recently picked up an oil additive meant to stop oil leaks (Bardahl somethingorother) Too soon to know if it helps, but I will let you know.

Also make sure you are using SAE 30 oil. It is not the same as car stuff (not 10W30 etc.)

Are you trying to say non detergent.
If I remember right, oil should be about 1/2 imp. qt = 2/3 us quart amd some portion of a litre. :confused:
 
Briggs&Stratton recommends SAE 30. You can use 10W30 but it will break down faster and need to be changed more often. You don't usually need the cold weather performance of 10W30 in a lawn mower.
 
Where do I buy specific parts for a lawnmower like spark plugs, air filters, etc?
 
Where do I buy specific parts for a lawnmower like spark plugs, air filters, etc?

I get most things at Home Depot these days. There will be a number on the plug that you can cross reference or take it with you and ask for help. Match up the air filter with a new one exactly like it.
 

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