Honda Mower Seized Piston

NJDan

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Hi. My first post in this forum!

I ran my Honda HRX217HZA with the GC190 engine dry of oil stupidly about a month ago. It seized up and I thought I was done until I started googling it. Apparently a lot of times the piston can be freed with some penetrating oil and a wrench. I removed the spark plug and the top cover where the pull cord is housed. This exposed a nut that is connected to the motor shaft. I was able to free up the nut and everything turns as it should. The pull cord now pulls. However, I am not getting any spark so nothing is happening.

In the process of figuring out the spark problem I noticed that I do not see any piston movement while turning the motor. I look into the spark plug hole with a flashlight and nothing moves. Does this mean I have a sheared part between the motor and piston, or is this normal? I'm not going to pursue the spark issue if I have a stuck piston.

Thanks for any comments!

Dan
 

StarTech

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Kinda doubt you have a horizontal engine on that mower. Anyway using a 6" wooden dowel in the spark plug hole slowly turn the engine by and you should feel the piston moving. If not then it is likely you have a broken connecting rod.
 

NJDan

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Kinda doubt you have a horizontal engine on that mower. Anyway using a 6" wooden dowel in the spark plug hole slowly turn the engine by and you should feel the piston moving. If not then it is likely you have a broken connecting rod.
Yeah I put a screwdriver in there and nothing happened.
 

bertsmobile1

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The pull start is slipping & not turning the crankshaft.
We get different models down here so we do not have to suffer those idiot blade brakes that make the whole mower taller , top heavy & hard to use so we can turn the blade plate to free up an engine or to check if the crankshaft is moving,
The starter works on a cup which is either sandwiched between the nut & flywheel or is keyed into the flywheel.
The flywheel is held to the crankshaft by a taper & positioned with a shear key.
Your flywheel probably broke free of the taper when the engine siezed
So pull off the blower housing then grab the fins and turn the flywheel
While doing so watch the end of the crankshaft to see if it is moving.
 

NJDan

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The pull start is slipping & not turning the crankshaft.
We get different models down here so we do not have to suffer those idiot blade brakes that make the whole mower taller , top heavy & hard to use so we can turn the blade plate to free up an engine or to check if the crankshaft is moving,
The starter works on a cup which is either sandwiched between the nut & flywheel or is keyed into the flywheel.
The flywheel is held to the crankshaft by a taper & positioned with a shear key.
Your flywheel probably broke free of the taper when the engine siezed
So pull off the blower housing then grab the fins and turn the flywheel
While doing so watch the end of the crankshaft to see if it is moving.
When I turn the blades the nut in the middle also turns. Originally originally nothing would turn so I so I put a socket on the nut and made it turn which was not too difficult to do. I'm not sure if that addresses what you were saying.
 

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NJDan

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Well if the crankshaft is turning but the piston is not moving then the connecting rod is broken
Unfortunately, I guess that's what happened. The shaft was frozen solid until I got it freed up with the socket wrench. Maybe the broken part was keeping the shaft in place until I moved it.

How difficult is it to replace a motor? These mowers aren't cheap and if I can find a replacement motor for a few hundred and it isn't too crazy to swap one out then maybe that is an option?
 

bertsmobile1

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First step is always to pull it out and pull it apart.
Then evaluate a repair against a replacement
Some times you get lucky.
Hardest part is getting the flywheel & the blade mechanism off.
Do both before you pull the engine out
 

NJDan

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First step is always to pull it out and pull it apart.
Then evaluate a repair against a replacement
Some times you get lucky.
Hardest part is getting the flywheel & the blade mechanism off.
Do both before you pull the engine out
Thanks for the suggestions. While I'm capable of DIY projects I've never disassembled a mower like this before. Are there any good references/step by step type info available to help things go more smoothly? Or, do I just start taking everything apart until the motor comes out? lol
 
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