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I have a John deere LT160 it wont start but this is what happens.
1. The starter gear comes up
2. It engages the flywheel
3. The flywheel turns
And thats all, no engine noises
The flywheel key was broke I replaced that and put in a new spark plug.
The battery is fine it worked about 2 days prior and now this
Any ideas?

where is the fuel shutoff solinoid?

With these revolting developments, let's check the timing and spark first even though it could be other possibilities.

Remove the spark plugs and put one plug back on its plug wire. While holding a thumb or finger on the plug hole and the side of the plug grounded to the head, have a helper crank the engine. If you have spark and the timing is correct, and you watch and listen closely, you will see spark at exactly the same time your thumb/finger is blown from the plug hole. This is a 2 birds with one stone test. Spark and timing. I recommend some eye protection for this test.

plug the hole were the plug used to be

i dont feel any compression

kevinjgray88 said:

i dont feel any compression

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AW Heck, I forgot about that compression test so I guess It's like killing 3 birds with one stone.:laughing:

A valve could be stuck open or if its a overhead valve engine it could be a pushrod problem.

is there anything else easy i could check before those two things you mentioned?
how would i check for a stuck valve. i really dont have much for engine knowledge:thumbsup:
thanks

kevinjgray88 said:

is there anything else easy i could check before those two things you mentioned?
how would i check for a stuck valve. i really dont have much for engine knowledge:thumbsup:
thanks

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It just doesn't get any easier or cheaper than those two things mentioned to test for spark, timing and now compression. If you can replace a broken flywheel key you can do this test.

How were you testing for compression to determine it had no compression?

I took off the valve cover and turned the engine over and both valves seemed like they were moving fine. no sticking or anything. I did notice some oil just under the valves is that normal? I did notice they were making a clicking noise tho also is that normal? it is a louder click. i check compression with my finger like you said. I know its not a guage but I didnt feel anything really just a little air movement

kevinjgray88 said:

I took off the valve cover and turned the engine over and both valves seemed like they were moving fine. no sticking or anything. I did notice some oil just under the valves is that normal? I did notice they were making a clicking noise tho also is that normal? it is a louder click. i check compression with my finger like you said. I know its not a guage but I didnt feel anything really just a little air movement

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The clicking may be caused by too much valve lash. Follow the service manual for setting the valves for your particular engine. It isn't difficult using the manual as a guide and inexpensive tools. If after setting valve lash the compression still won't blow your finger from the spark plug hole it is time for a trip to a reputable small engine shop.

To answer an earlier question - the electric fuel solenoid shut off is often at the bottom of the carburetor bowl. If one thinks a lack of gas is the culprit for not starting, a teaspoon of gasoline can be placed directly in the carburetor throat after removing the air filter and an engine will run until that fuel is used up.

I sprayed some fluid into the carb and still nothing new. I am thinking its something stupid simple like popped fuse or anything like that.
when this problem first came up I went to start it and the flywheel would make about one turn and stop dead like it hit a wall. then you could spin the flywheel backwards then start it and same thing.
So I tore it down to the flywheel and it just freed itself some how and did not do it anymore but still just cranks with no start

All along I've been wondering what caused the key to shear. Most often a sheared key is caused by an abrupt engine stop where the flywheel inertia overcomes the forces of the two tapers the shaft and flywheel are assembled with.

QUOTE: when this problem first came up I went to start it and the flywheel would make about one turn and stop dead like it hit a wall. then you could spin the flywheel backwards then start it and same thing.
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This is going to be difficult to diagnose over the internet so if what I said in an earlier post doesn't work it will have to be shopped. I'm sorry I can't be of more help.

"If after setting valve lash the compression still won't blow your finger from the spark plug hole it is time for a trip to a reputable small engine shop".

SandburRanch said:

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AW Heck, I forgot about that compression test so I guess It's like killing 3 birds with one stone.:laughing:

A valve could be stuck open or if its a overhead valve engine it could be a pushrod problem.

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Christ, how big is this stone!? :laughing:

jmurray01 said:

Christ, how big is this stone!? :laughing:

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Oh it gets bigger. Nearly the size of a meteor since at the same time we are also testing the ignition switch, solenoid, safety switches related to cranking and maybe the head lamps. I don't think it covers the tire pressure:laughing: Let me know if I omitted anything.:biggrin::biggrin::biggrin:

SandburRanch said:

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Oh it gets bigger. Nearly the size of a meteor since at the same time we are also testing the ignition switch, solenoid, safety switches related to cranking and maybe the head lamps. I don't think it covers the tire pressure:laughing: Let me know if I omitted anything.:biggrin::biggrin::biggrin:

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It also tested the gauges, warning lights, battery, and the ability of the owner to turn the key! :laughing: So, it killed 11 birds with one big, big stone!

It sounds like your piston push rod has broken and that's why you have no compression and all the other symptoms. May be repairable but probably not.