Lawn mower engine won't stay running...

I just got a lawn mower from a neighbor. He found it who-knows-where, but he's always fixing something, so I figured it would work. Well, I went to mow the lawn and I couldnt start it. I primed it up with a few more pumps then recommended and I got it to start, but after a few seconds it would shut off. After priming it/starting it/priming it/starting it/priming it/starting it..... about 6 or 7 times, it stays running for a while. I haven't tried mowing the lawn yet, because I don't want it to shut off in the middle of the job. The engine "looks" like it's in good shape, any ideas of what it could be and how I could fix it?

 

Hello and Welcome Gonzales to the Do-It-Yourself Web Site and my Small Engine forum.

When dealing with used found power equipment, one never really knows why the previous owner tossed...
However, there are some gems to be found among them...

There are two problem possibilities that you need to explore listed above. Try verifying if there is spark at the spark plug when the engine dies. It may just be a defective spark plug.

Another reason may be the engine is starving for fuel.
You'll need to remove the fuel hose from the carb and check fuel flow.

If that appears fine, then the carb may be gummed up.
In that case, the carb will need to be removed, dissasembled, cleaned out and rebuilt with a new carb kit.

The carb kit may not be needed if your able to dissamble the carb and not damage any delicate gaskets, etc.

Check the archives, within this forum, for more information.
Several other postings and replies to this topic with helpful information can be found there.

Check the manufacturers online web site for additional help.

Regards and Good Luck,
Tom_Bart.....
Small Engine Forum Moderator
"Accurate Power Equipment Company"
Small Engine Diagnostic Service and Repair Technician.
Personal Quote:
"If it ain't already broke, don't fix or tinker with it until it is broken!"
Bare in mind my company no longer services nor repairs small engine powered equipment. The information provided is accurate to the best of my knowledge.

 

Could be water in the gas tank and or just the fuel bowl. Unsrew the nut holding the float bowl and pull the float bowl off. The other possibility is that the holes in the screw are clogged. Get a set of welding tip cleaners and make sure that the hole that is in the nut assembly is clear and also try cleaning down inside the nut.

 

What brand of engine do you have? Quick tune ups for used engines are to clean fuel system, clean the flywheel magnet, check/replace the spark plug. Oh, and don't forget the oil. Water in fuel tank, clogged fuel inlet screens, old fuel, are common problems.

 

I would agree with the other folks that it sounds fuel related. My experience working in a rental yard on mowers, tillers, etc. is that over the years they get a lot of goop into fuel system. Often the motor would start and the carb would suck the offending material up into it (causing the engine to stall). When the engine stalled, the suction would release allowing the crud to sink back into the fuel supply. Sounds like a good carb cleaning and fresh fuel would do wonders.

Good luck,
Paul

 

Hi;
Is the mower that was given to you a Toro? I have had several and have had problems similar to what you describe.
I have found on them that if you look down at the carb and see a brass screw with a hole in it , carefully remove the screw and clean it and its cavities. This is abreather screw and floats with the engine vibration. Grass debris and dust collect in the hole and preclude it from allowing air passage ( or whatever it does! LOL!!). Do not retighten securely only to where some resistance is felt so that the screw will vibrate with the engine on. This has worked for me in the past and I include it in PMS checks.