Toro Walk-Behind Runs Really Sloooooow

Now days, we discuss mineral oils on boxes which light up. Then, we burp, fart, and scratch our butts. Not much has changed.

Update:

I've changed the plug and the air filter.

I've changed the fuel - after mixing in some carb cleaner and running it through.

I've made sure the ecreen at the bottom of fuel tank is clear.

I've made sure the hose from the tank to the carb and the hose from the carb to the engine were clear.

I sprayed all of the exposed linkages and springs with cleaner to de- gunk them.

I dropped the bowl and cleaned up the float and needle - without removing anything except the bowl.

Nothing helped. The mower runs fine for a few minutes after each start and then drops to a really slow, almost-stall-but-not-quite speed.

I'm thinking it's shop time...

Loosen the gas cap, see if helps. Using a paper clip you can pierce the hole in the cap, to ensure it is cleared. The fuel tanks needs to vent.

Does the engine have a coil? Perhaps it is cracked and runs like this when the coil heats, expands and leaks?

Two things come to mind. First, the oil. As strange it sounds, many mowers don't run worth a hoot on cheap oil. Try Castrol, that's the brand I like.

Second, makes me wonder what's with the speed governor. Might need new carb throttle springs.

The vented fuel tank idea is very good.

Most gasoline engines have an ignition coil. So, I think it's likely he does have one on that mower. You're right, that they do go bad. But often they short out and the mower dies. Engine slows down, doesn't sound like bad coil.

to the OP, please remove the motor cover, and clean any dirt, leaves, etc, from under the motor. Walking mowers are air cooled. Any dirt will cause the motor to run hot, and that isn't good. Might be part of your problem. The end of the motor where the spark plug goes in, that has be clean of dirt. Also good to clean off any oil or grease from the cooling fins.

I'll check the vent cap.

The mower is clean, up, down and all around.

I spoke to a local guy that repairs small engines. He said that it's possible that the timing is off, but that there is no timing adjustment on this engine.

He said that if the engine has ever been run with little or no oil then something might have warped which could throw the timing off. If that's the case, then the mower is toast.

In any case, he normally charges $55 for a complete tuneup but since I've done anyway, he said he'd look at it for $20 and let me know what he thinks.

I'll let you know what he finds.

edit:

In any case, he normally charges $55 for a complete tuneup but since I've done most of what he would do anyway, he said he'd look at it for $20 and let me know what he thinks.

Yes, I'm curious what turns out to be the real problem.

He has the mower now. I'll post back when I get an answer.

He says it needs a carburetor. He said it runs fine until it draws a vacuum and slows down.

He says there's a rebuild kit available for about $12 bucks but the jets might still be gunked up, so he suggested replacing the carb for about $65.

He said he does these tune-ups on the side and doesn't want to get into guaranteeing a carb replacement just in case he's wrong and has to eat the $65. He suggested I order a carb, throw it on there and see what happens. He even said to call him if I run into problems.

No charge for what he tried since he didn't fix it.

-snip-

Good man. Sounds like my neighbor. I like

for carbs.

His search engine fails me sometimes, so try Google's 'search site' thingy with the part number if you can't locate your carb.

Jim

Thanks. I'll check out that site.

Update:

Problem solved - I bought a new mower!

When I picked up the mower from the guy who told me I needed a carb, he said it was running just like it was before - starts fine and then slows. That was about 2 weeks ago and I just hadn't gotten around to ordering the carb.

Last Friday night I decided I had to mow, so I tried to start the mower. After a couple of pulls I heard a loud "clank" from under the bed. I lifted the mower to find the blade and half of the blade mounting assembly on the ground. The mounting assembly had failed on this mower a few years ago, so I knew right away what was wrong.

Over the past week I had shopped for a carb and found the cost to be around $80 - $85 with shipping. I know from past experience that the blade mounting assembly was about $20. So now I need over a $100 in parts and at least a couple of hours of labor.

I looked at the bald front wheels, reminded myself of how rough the self-propel mechanism was working, thought about how it was time to get the blade sharpened and said "See ya! Time for a new mower."

The replacement Toro mower (same features, this year's version) was $279 at HD. Just about every model that had the features I wanted was $275 - $300.

Went to Sears and found a Craftsman Limited Edition with a Honda 160 CC engine, regularly $399, on sale for $289, one left. =93Thank you, just load it into that van right there.=94

Put the old one at the street, with a sign that said Free! Needs Carburetor and Blade Mounting Assembly". It was gone by the next morning.