Lawn mower smoking? Reasons why and how to fix it!

hey guys welcome back to the channel and in this video I'm going to be talking about reasons why your engine may be smoking I'm going to discuss what causes what to look for and how you guys can possibly save a lot of time and money and avoid you know by avoiding a trip to the repair shop as you can see this engine's smoking like we're at a Kiss concert but we're going to go over a lot of reasons why what to look for so let's go ahead and get started if you haven't already hit that like button and also hit that subscribe button that really helps me out first I'm going to start off with the most common reasons and those are also usually the easiest things to fix a lot of times customers bring in their Mower and their engine smoking that bad and they're in fear that they have a major problem with their Mower and a lot of times most of the time it's not a big issue to fix they could have fixed it themselves and that's why I'm going to make this video to help you guys out and maybe avoid being taken advantage of by some repair shops first off the color of the smoke is going to give you a good indicator of what is going on white or bluish smoke is usually oil and black smoke is usually fuel and by Fuel I mean unburnt fuel that's why when you see a car or more like a diesel truck or a semi truck when they're accelerating you see that black smoke coming out that's usually that or that is unburned fuel basically is what you're seeing all right but first the most common reason I see engines come in smoking is that the engine is overfilled with oil now the first thing you need to do is know how to correctly check your oil level on your specific mower your specific engine some of them are different some of them want you to turn the threads all the way down some of them don't and sometimes it usually will say on the dipstick on this mower's engine for example we have the oil operating range you don't want to go above that full Mark and on this one it says four correct oil level do not turn cap on threads so basically I'm just going to set it down in there and pull it out and as you can see this engine is over filled with oil this next engine I'm going to show you has a different style dipstick or it goes all the way on down in that's on a John Deere Gator push it all the way down pull it out and this one is as you can see I'm trying to get the camera angle here a little better it's way over filled with oil when I see the oil level this High what I like to do is smell of it to see if there's gasoline in it now in another video I made in the past I'll put a link down in the description I showed you how you can detect if there's gas in that oil if you can't smell like I've lost a lot of my ability to smell maybe it's 20 percent so if I smell gas on that dipstick I know it's got a lot in there but if you're like me and you've lost or you're hard of smelling here's a little trick you can do to confirm if there's gas in that oil what you want to do is take that dipstick and put it down into some nice clean water and like a cup of water and you'll be able to see the gas spread out in the water the oil will stay with itself it won't move away spread out in the water so the way the gas is getting over into your engine oil is usually by a faulty fuel pump they use a little plastic fuel pump that normally has three hoses one of them that's taken vacuum pressure from the crank case and that's what's operating the pump another hose pulls gasoline from the tank and then the pump is pumping that gasoline over to the carburetor and what happens is when those diaphragms inside of that fuel pump go bad it's letting gas get over into your engine oil and it's letting oil get over into your gas and so you have two reasons then your engine is smoking you got your crank case engine oil is over filled plus it has gas in it and then your gas has oil in it so you have two major reasons working together to cause that white smoke so let me show you what I'm talking about here this lower hose is the one that's operating the pump off the crankcase pressure this other hose with the fuel filter that's pulling the fuel from the tank and then this other hose sends it over to the carburetor and if that's full of oil or has some oil in it it's going to cause smoke and here is the fuel pump on that Gator that I was showing you a moment ago there's the crank case hose again we have the other hose here I'm going to show you here in a second with the fuel filter coming from the tank runs up to the pump and if those are bad you're you know you may be getting oil in that hose going over the carburetor and oil getting it or gas getting over into your engine oil so if this ends up being your issue you're going to need to change your oil too and just use the oil that the engine manufacturer recommends and once you have that done you're going to need to crank it up and you may need to just burn all that excess excess oil out of the muffler that it received in there before like that's what I'm doing on this mower here this is actually the mower in the beginning of the video that was smoking really bad all it needed was a fresh fuel pump and the oil changed and the problem is solved now very simple easy to do yourself at home and one other thing I want to mention is if you've operated your mower at a steep angle this also can cause that engine to smoke for a period of time and you may need to just let it run and burn that engine oil out of the muffler all right so so far we've kind of covered white smoke blue smoke oil burning smoke basically so if you've confirmed that your oil is not overfilled and your fuel pump is good you don't have gas and oil mixing up together and you're using the proper oil at the proper level and you haven't been going at extreme uh degrees of angle operating your mower and you're still getting some white or bluish smoke now you're kind of getting into some more serious issues um not too bad not horrible you could have some valve seals leaking worn valve guides could be a head gasket and in the worst case scenario your piston rings all right so if that's the case a mechanic's going to be able to do a leak down test to see if it's a head gasket or piston rings and to solve that smoking issue now if you have a your smoke is black like I said earlier in the video that's usually a fuel issue and if that's going on what I would recommend doing if you're having black smoke first look at your air filter if that air filters restricted clogged up now you're going to be getting a rich fuel mixture into the combustion chamber it's not gonna you're gonna have too much fuel versus the air also check out your spark plugs your spark plugs may need to be changed you're not it's not they're not igniting the fuel a hundred percent or properly uh and then if the if the spark plugs and air filters are good and you're still getting black smoke you're probably going to have a carburetor issue and like I said before it's normally the easiest things to fix is is more common it's very uncommon that I see one that's smoking due to um belong you know worn out piston rings which is the worst case scenario you know if it's a head gasket or piston rings you know you're probably going to want to take it into a mechanic a head gasket it's not that bad to do valve seals and things but you really need to kind of know what you're doing to change that but all this other stuff fuel pump air filter spark plugs even a carburetor that's stuff you guys can do at home and save a ton of money so that's going to do it for this video I hope I shed some light on it helped you helped you out if you're having a smoking issue with your mower do me a favor hit that like button hit that subscribe button check out some of my other videos I've got a lot of other videos covering these topics that'll help you guys out save a lot of money and do me a favor subscribe and I'll see you guys next time with more videos like this coming soon thanks thanks for watching

Channel: Mechanical Mind

Views: 57,985

Keywords: lawn mower smoking, lawn mower engine smoking, why a lawn mower is smoking, how to fix a smoking lawn mower, engine smoking, engine has white smoke, white smoke from engine, blue smoke from engine, why is my lawn mower smoking, lawn mower smoking bad, lawn mower smokes, mower smokes after starting, lawn mower repair videos, lawn mower backfiring

Id: atXjMQmb1b0

Length: 9min 56sec (596 seconds)

Published: Thu May 18 2023