Does Flywheel Key Need Replaced? (pic included)

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MonkeyCam

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• Mar 9, 2017 / Does Flywheel Key Need Replaced? (pic included)

• #1

Last fall I got a deal on a used Snapper rear-engine rider that was manufactured around 2010. It has a Briggs & Stratton Intek 12.5 HP OHV engine on it. I didn't start it, just brought it home & parked it in the garage for the winter. Now I'm trying to get it in shape for the season, but I can't get it started. I've been troubleshooting & trying diff. things, but no luck so far. My research has led me to believe that the flywheel key may be the problem, so I removed everything necessary to have a look. The key hasn't been sheared off, but it *does* look a little off to me. Just wanted to get some opinions of those more knowledgeable & experienced than a beginner like me. Could this flywheel key be causing (or at least be part of) the problem, or does it look OK? Is it worth going to the trouble to replace it or not?

 

RDA.Lawns

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• Mar 9, 2017 / Does Flywheel Key Need Replaced? (pic included)

• #2

Looks like its sheared to me. I'm not certain but looks like the key way could be bad in the crank. You need to pull the flywheel and have a better look.

 

BlazNT

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• Mar 10, 2017 / Does Flywheel Key Need Replaced? (pic included)

• #3

Yes it needs to be replaced.

 

reynoldston

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• Mar 10, 2017 / Does Flywheel Key Need Replaced? (pic included)

• #4

It looks to me like someone installed a steel keyway and they damage the crankshaft. Remove the flywheel and take a look.

 

pugaltitude

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• Mar 10, 2017 / Does Flywheel Key Need Replaced? (pic included)

• #5

I would say that it needs replaced but I wouldn't say it would cause a non start issue.

 

reynoldston

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• Mar 10, 2017 / Does Flywheel Key Need Replaced? (pic included)

• #6

pugaltitude said:

I would say that it needs replaced but I wouldn't say it would cause a non start issue.

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Don't agree, very much a non start issue. I find if timing is off by very little on small engines it can be a starting issue. Very simple and cheap repair if all it needs is a key to find out if its a non start issue. Fuel, spark, compression and TIMING and it will run and you know timing is off.

 

pugaltitude

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• Mar 10, 2017 / Does Flywheel Key Need Replaced? (pic included)

• #7

reynoldston said:

Don't agree, very much a non start issue. I find if timing is off by very little on small engines it can be a starting issue. Very simple and cheap repair if all it needs is a key to find out if its a non start issue. Fuel, spark, compression and TIMING and it will run and you know timing is off.

Click to expand...

But I don't think timing is off enough to cause a non start. You get some movement when you tighten the bolt on the flywheel which makes it look as though its sheared. Also its only got a pulley on end of crankshaft so belt would usually break before shearing key but it can happen.

I assume its a model 21,28 with the look of the flywheel so guessing valve, head gasket or carb issue.

 

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ILENGINE

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• Mar 10, 2017 / Does Flywheel Key Need Replaced? (pic included)

• #8

It doesn't take very many thousands off on the flywheel key to make a big difference in the timing.

 

reynoldston

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• Mar 10, 2017 / Does Flywheel Key Need Replaced? (pic included)

• #9

ILENGINE said:

It doesn't take very many thousands off on the flywheel key to make a big difference in the timing.

Click to expand...

Now this I do agree on and think it would be where to start to get this engine running again. Valves and head gasket, check the compression. Carburetor, spray some starting fluid in it and see if it fires. Test for spark and a new spark plug. All cheap and easy things to try.

 

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MonkeyCam

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• Mar 11, 2017 / Does Flywheel Key Need Replaced? (pic included)

• #10

Thanks for all the replies; I appreciate the input. Tonight I got the flywheel off. The key was not broken, but it *does* look like it was at least stressed significantly, b/c it was gouged on 2 opposite sides. There was also a TON of caked-on dirt packed inside the flywheel & under it all over the coil & the top of the engine that I scraped off, blasted off w/ a can of compressed air, & also vacuumed off. I wonder if all that crud interfered w/ the functioning of the magnets & coil. Tomorrow I'll put everything back together & try to start it again. Fingers crossed.