I came into possession of a brand new Poulan push mower. It was a return due to not starting. I was told to make it go away, so I made it go away to my house. Again, it is brand new.

Problem is every other pull on the pull starter causes a severe kick-back, which rips the pull handle out of your hand and hurts like hell. On the pulls that are smooth, it acts like it wants to start, but will not get going.

I pulled the plug and pulled the handle and it is smooth as silk, and I tipped it over and nothing came out of the cylinder, so no hydrolock. Oil level is perfect. Fuel is new. I removed the air cleaner and sprayed some starting fluid into the carb and tried to get it going, and the kick-back was ferocious. I also pulled the valve cover off to see if there was anything amiss in there, and all looked fine, and everything worked smoothly when I turned the blade to make it go through the cycles.

I will probably take it to a small engine repairman to see if there is something simple wrong, but thought I would see if anybody on here has an idea as to what is wrong or to check. Thanks.

sheered flywall key?

0708aggie said:

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sheered flywall key?

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That is the exact same symptom I have. Thank you for the video, I am going to go check that key this evening and see if that is the culprit.

EDIT: Nope, a broken key was not the problem. I know it has spark, fuel, and air....and by god it has compression for sure. The handle is really hard to pull, then gives way, then snaps back really hard. I am stumped on this one.

Yep, had same symptoms on an old mower. Replacing shear pin fixed it.

Sweet Kitten Feet said:

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Yep, had same symptoms on an old mower. Replacing shear pin fixed it.

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This one has a regular half moon key, and it is in great shape and holding fine. Something else is wrong here. It backfires through the carb when it tries to start. Absolutely nothing out of the exhaust. I will remove the exhaust to make sure it is not plugged in any way.

Have you checked the blade? Is it on tight?

https://support.cubcadet.com/s/article/451-1

That shows your typical culprits.

Just spitballing here...is the pull cord wound properly?

Timing seems to be off somehow.
I'm really surprised it's not the flywheel key. I had the same symptoms on my hrx and found that the key had sheared.

Loose valve is my guess assuming it's a 4 stroke.

clarythedrill said:

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Sweet Kitten Feet said:

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Yep, had same symptoms on an old mower. Replacing shear pin fixed it.

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This one has a regular half moon key, and it is in great shape and holding fine. Something else is wrong here. It backfires through the carb when it tries to start. Absolutely nothing out of the exhaust. I will remove the exhaust to make sure it is not plugged in any way.

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That's my guess. If it's brand new, I wonder if the exhaust gasket got put on but didn't have the actual hole cut in it to let exhaust out through the middle.

Probably timing. My weed eater does it from time to time, on the second engine (replaced under warranty) both had the same issue. If you could ****** the ignition it would fix it.

What I meant to say, but the butthurt nanny starred it out is lower the IQ of the electronic ignition to democrat level