Month: April 2019

Lawn Mower Repair Tips

My lawn mower is leaking gas

A gas leak can be a dangerous situation that can lead to a fire. You could come out to the garage and smell gas and find a puddle under the lawn mower. The first thing to do in that situation is turn off the gas at the shutoff if it has one and then push it outside. You don’t want to take the risk of it catching fire in a garage or outbuilding.

Gas line connections are a common place where leaks occur. Gas line fittings in the bottom of gas tanks and gas filters are areas that commonly leak.

The lawn mower can also be leaking from the carburetor. The needle and seat is where the leak develops as the needle does not seat properly. Fuel then goes through the carburetor and into the cylinder of the engine. Then the gas will seep past the piston and into the crankcase and can fill it up to overflowing.

Your next step should be to take your lawn mower to a repair specialist who can properly diagnose this problem and resolve it. Gas leaks are a serious safety hazard and with some lawn mowers holding several gallons of gas, you don’t want to chance making a repair that might fail and cause a fire.

By inspecting your lawn mower each time you use it, you can catch that gas drip before it turns into a full blow leak. My lawn mower is leaking gas is a serious situation and should be remedied quickly.

 

Lawn Mower Repair Tips

My Lawn Mower is Surging

Carburetor Jet Plugged

A surging lawn mower is one of the most common problems that an engine has. It normally occurs in the springtime when you first pull out your lawn mower to get it ready for spring. You start it up and then it may slightly surge or it will be extreme. The engine gains RPM and then loses RPM and this cycle will continue nonstop until the condition is repaired.

The mechanics behind it is quite simple. The engine is being starved for fuel. The carburetor jets are plugged up and the engine will suck a little fuel to keep it running and then will start to run out of fuel. Then the engine governor comes into play. As the engine is losing RPM, the governor flyweights retract and will try to increase the RPM by opening up the throttle more. So a little fuel comes in again and the cycle repeats itself. This condition is known as a lean surge.

Air Leak

There could be another factor in play here. An air leak could have developed in the intact tract between the carburetor and the engine. When there is an air leak it will pull in more air than fuel and result in a lean mixture. The engine will run for a short time and then the surging will begin. There is less fuel to burn so it does not produce the power required to keep the engine running. The surging is usually worse at idle than at full RPM.

Elevation

I want to throw in a third possibility and that is elevation. When you live at high elevation, your carburetor fitted engines should have the main jet replaced with one for high elevation. Everyone calls it a high altitude jet, but altitude means the distance above the ground so that is not the correct term unless you are working on an airplane. This problem can also be worse at low RPM. The cause of this problem is that a standard elevation main jet has a larger hole for the fuel to flow through and you need less fuel when you are at a higher elevation because the air is less dense. Less dense air means less air molecules to burn with the fuel mixture. So you will have the wrong air to fuel ratio and will get too much fuel and run richer than normal. This condition is known as a rich surge.
By knowing the symptoms of these individual problems, this should help you diagnose them. Take your lawn mower to a reputable repair shop to resolve my lawn mower is surging.

Lawn Mower Repair Tips

How To Buy a Good Used Push Mower

So you have a small yard and only need a push mower to cut it instead of a self-propelled or rider. That simplifies things immensely and with these tips it will help assure that you get a good one.

I have been a push lawn mower repair technician for over 5 years and from that experience I can tell you what to look for and tests to do when looking at your prospective used push mower.

First I would stick with the major brand names of engines. Briggs & Stratton, Honda and Kohler are the most popular although you probably won’t find a Honda engine on a push mower. More than likely it will be a Briggs and Stratton which is perfectly fine.

For the most part the decks, handles and controls are basically the same. The deck will be a stamped piece of metal but it could be a welded deck. Welded decks are much heavier and will last for a long time.

The engine should start on the first or second pull. If it doesn’t, that is a good time to move on. If the push mower has sat for an extended period of time, it may not start on the first or second pull so take that into consideration.

Check the engine for any oil or fuel leaks. Check the engine oil to see if it is black and the quantity of it. Is it low on oil? Black oil is a sign that the engine was probably not maintained as well as it should be. Is the engine dirty or have spots of grass stuck to it which would indicate an oil leak? Grab the engine (after it has cooled) and try to move it around to see if there are any loose mounting bolts.

Check the control cables for fraying and ease of operation. Does the safety bail spring back or does it slowly retract. It should spring back after you release it.

Pull the spark plug boot from the spark plug  for safety and look under the deck to see if there is rusting or if there is a large buildup of grass under it. Wet grass will lead to rusting of the deck and it can rust completely through.

Check out the blade for straightness and sharpness. Is it worn out or worn down and needs replacing? Are there any big nicks in the blade that would indicate it struck something?

Lastly, roll the mower and pay attention to the wheels. Do they spin freely? Are they leaning outwards or inwards? Are they broken or the tread is worn down?

If you suspect anything that is not quite right about the push mower, ask the owner to clarify what service work has been done. They may or may not know or choose to not answer your question.

I hope this arms you with enough information to make a good informed choice in how to buy a good used push mower.

Lawn Mower Repair Tips

My Lawn Mower is Blowing Black Smoke

To understand this problem, you also must know that there are different color smokes that a lawn mower can blow out the exhaust pipe. Blue, black and white smoke are the colors that you would normally see and in this article we will concentrate on black smoke.

Black smoke means that the engine is running rich. Running rich means that the engine is getting an incorrect fuel/air mixture. It is getting more fuel than air and thus burning in a rich condition. A clogged air filter is often the culprit here.

Black smoke is normally a rich condition. In most cases the engine is getting too much fuel to burn and cannot burn it all thus making the black smoke. The engine could also not be getting enough air. Things that can cause this is an air filter that is very dirty or a setting in the carburetor or fuel injection that is incorrect.

Try removing the air filter and inspecting it for dirt buildup or grass clippings. If it is clogged, purchase another filter and install and then test the engine. Carburetor or fuel injection settings should be performed by a qualified lawn mower repair technician.

Each lawn mower engine smoke condition has its cause and by knowing what color to look for and the steps to take to correct it, you can cure the my lawn mower is blowing black smoke problem.