My son was attempting to follow my instructions to mow the lawn. I did not tell him to add any oil but he wanted to be safe. Unfortunately due to his ignorance he added mixed gas to the oil reservoir.

He ran the mower like this until it shut off and he couldn't restart it. I got home and did some investigating and determined what happened.

I drained the oil/gas mixture out and replaced it with oil. The mower will start and run for a few minutes before shutting off. It won't restart immediately but it will restart after several hours.

Any suggestions for a fix or am I looking at a replacement.

It is a toro push mower with a tecumseh engine he purchased at lowes.

Does it make any rattling noises when running, feel more resistance when pulling to start or have metal in the drained oil?
How much gas did he add to the oil?

Pull the spark plug and clean it really well. Check the gap while it's out & re-install.

Cheers~

Maybe pull the head and look to see if the cylinder walls are scored or there is any visual damage as might be fine until it reaches temp and then things start expanding?

Funny side note:

I did almost the same thing when I was a kid with an old lawnmower that my dad had at one of his rentals for me to use when I cut grass in summer. He clearly told me to always check oil and I clearly did not resulting in nicely seized motor.

My Dad gave me two options.

1) Pay to have it fixed

2) Fix it myself

I opted for door number two but had zero idea what to do. My Dad new this and handed me a Briggs & Stratton shop manual and then looked over my shoulder while I removed, tore down, fixed and rebuilt the motor.

One of the best lessons he ever taught me

I forgot to mention I already replaced the spark plug and air filter but maybe the plug got fouled again.

My guess is that he scuffed the rings. Sounds like when it heats up it seizes. When it cools off everything shrinks and it will run again temporarily. It’s probably trashed, but I would at least try synthetic oil in it. It’s supposed to lubricate better in high heat situations.

quote:

Originally posted by 220-9er:
Does it make any rattling noises when running, feel more resistance when pulling to start or have metal in the drained oil?
How much gas did he add to the oil?

No rattling or extra resistance and no metal in the oil. I am not sure how much gas he added since it was mixed 50/50 gas oil mixture

quote:

Originally posted by Apphunter:

quote:

Originally posted by 220-9er:
Does it make any rattling noises when running, feel more resistance when pulling to start or have metal in the drained oil?
How much gas did he add to the oil?

No rattling or extra resistance and no metal in the oil. I am not sure how much gas he added since it was mixed 50/50 gas oil mixture

50:1? I think 50/50 would be kind of unusual.

quote:

Originally posted by arfmel:

quote:

Originally posted by Apphunter:

quote:

Originally posted by 220-9er:
Does it make any rattling noises when running, feel more resistance when pulling to start or have metal in the drained oil?
How much gas did he add to the oil?

No rattling or extra resistance and no metal in the oil. I am not sure how much gas he added since it was mixed 50/50 gas oil mixture

50:1? I think 50/50 would be kind of unusual.

yeah 50:1 sorry

The facts that there was no metal in the oil and it doesn’t seem to be harder to pull the starter cord are kind of encouraging. Maybe PhPaul will step in. He fixes stuff.

When it quits, HOW does it quit?

Just cut off like you shut the switch off or start slowing down like something's getting tight and then quit?

If it's cutting off, it can probably be fixed economically. If it's slowly grinding to a halt, I wouldn't bother. You can get a new Predator engine from Harbor Freight way cheaper than you can rebuild a Tecumseh/Briggs and Scrapiron/Other. I replaced a C-series Honda on a pressure washer with one and have been very pleased. They're a Chinese Honda Clone but they're a heckuva engine for the price.

MIGHT be worth messing with if it's a G-series Honda. If it's a C-series Honda, see para(3) above.