Thursday, July 6, 2017

How to fix a seized motor on a small engine mower.

With the beginning of spring and summer, most of us begin breaking out the long equipment that sat dormant for the winter.

If your like me, you don't really worry about adding fuel stabilizers, changing motor oil or even care to check if your equipment has oil as they will run forever....right? Unfortunately, you may find out
the hard way like I did this weekend when I seized up my mower do to low engine oil. You see, I actually had a small leak that I never noticed and come to find (as I was mowing) that no oil equals bad thing for your equipment's engine.

As I was mowing, I felt my mower starting to bog down. I actually thought that I was running out of gas, so I checked the tank only to see there was plenty in there. I then figured maybe I just hit a high patch if grass, so I went to pull start it again, but it was completely locked up!

Not only was I upset because I destroyed a perfectly good machine (so I thought), I was also embarrassed because I actually let this happen in the first place. After standing there for about 45 minutes with a look of shock and disbelief on my face, I started thinking about the three options I had.


Option #1. (Throw it out) and mope about what I have done for the next moth. Even through the motor would not turn, it just felt wrong to throw out a shiny mower.

Option #2 (Take it to a repair shop) This option was the most expensive one, but was it even worth the time and money. Most repair shops charge you so much money in BS charges, it's cheaper just to buy a new mower.

Option #3 (Fix it myself) This seemed like the cheapest and most logical option, but I have never really worked on a seized motor before, so would it even work?

So this was it, I was either going to fix this mower myself or it was going in the trash. I began looking on the internet for "how to fixe a seized motor," but most videos that came up were for larger car and truck motors. I then typed in "how to fix a seized lawn mower engine," and Jackpot!

After watching a few of these videos, I began to hear the name of a familiar product being mentioned over and over (PB Blaster). I have used PB a few times before to help take out rusted bolts and screws, but would it really fix my seized up mower motor? I actually thought that this was some sort of joke, as an 11 ounce can of this only runs around $3.00, and a mechanic would have cost hundreds.

How to apply the PB Blaster

I looked around in my garage and actually found an old can that I had purchased a few years ago for a different application. I then located the spark plug on the mower, and removed it completely. Once the spark plug was out, I sprayed a generous amount of PB into the hole where the plug once was. Now when I say generous, I mean about a quarter of the can was sprayed into the hole as I really wanted to make sure that I had enough in there to do the job. After the PB was in, I tilted the mower back and let it sit over night.

The next morning I sprayed more PB into the hole, and went to work. When I came back, I figured that I had applied more than enough to the motor (1/2 can) and should be ready to go. Before I installed the spark plug, I tried pulling the cord, but it was still stuck!!! Did the videos lie to me? did I let the PB blaster that I found sit in the garage to long and go bad? Was I doing something wrong?

The next day I went back to work with a defeated look on my face when an engineer in my department came up to me and asked what was up? I told him the issue that I was having, and he asked me if I tried turning the shaft after I let the PB set? He went on to explain that when the shaft turns without oil, it will heat up and will actually begin to rust. This is what makes it so hard to turn, and that is why the PB Blaster works so well. So the same day, I went home I tried to turn the blades manually. I felt them give a little, but not much. I thought that I needed a bit more power to turn the shaft, so I went and grabbed my Ridgid Impact Gun and placed it over the nut holding the blade on. I adjusted the impact gun to tighten (not loosen) and began to hammer away on the nut. immediately the shaft began to turn bit by bit. It was not a smooth turning, but a tic, tic tic motion. I added more PB to the spark plug hole, and hit it again with the impact, and all the sudden, the shaft started to turn freely. It was turning so well, I was actually able to turn the blades by hand, which completely surprised me.

After I felt that the shaft was ready to go, I put in the spark plug, added new oil and pulled the cord. One pull and it started right up, but I needed to run it for a bit. I took it out into the yard (not to cut) just to let it run for about 20 minutes to let the shaft lubricate fully. After the 20 minutes were up, I started it up a few more times just to make sure that it was ok, and each time I pulled the cord, the mower started immediately.

I was completely shocked that this method actually worked for me. I am not a small motor mechanic by any means, but I felt like a diy rock star that day. Not only did I get the gratification of fixing this mower myself, but I saved myself hundreds of dollars.

Buy Online, Pick Up in Store. Now available at a H Now, I'm not going to go into how or why PB Blaster, and/or other penetrating oils work as you can find other articles on that, but they do. It really doesn't matter if its a seized motor or rusted bolt, these oils are life savers, and just to recap how I did this, I will post the steps below.


1. Take out spark plug
2. Take PB Blaster or other penetrating oil and spray good amount into spark plug hole
3. Tilt mower upward
4. Next day spray again, set mower on all four wheels (level) and let set a few more hours.
5. Spray a bit more oil into hole, try to turn blades/shaft manually.
6. If shaft does not turn, use an impact or cheater/breaker bar to help.
7. Once shaft begins to turn, add more penetrating oil into the plug hole.
8. Once shaft spins freely, put in new oil, replace spark plug and start using pull cord.
9. Start mower and let run for about 20 minutes.

And that's all there is to it!

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