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Wali

Honda 400ex WONT START HELP

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I was riding my 400ex one day and when i shut it off to put it in the garage i tried to start it put again to drive it into the garge and it wouldnt start.I put a compression tester on it and its like 30 psi with out throttle and 0 psi WITH THROTTLE.

when i put my finger over the hole it fell likes its pulling my finger in more then its pushing it out 

 

Has good spark.When i took it into the shop the said it had 1oz of oil in it and a tiny pit of metal shaving(TINY BIT LIKE 30 flakes)

When i try to pull start (push start/roll start) it made a not normal sound  and wouldnt stay running.

If my bottom end is blow why would it still turn over fine,

Are my valves siezed or not working properly 

or is my timing off causeing valves to not open in correct order with fire 

PLEASE HELP all help is appreciated 

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This could be one of so many things.  Engines that blow the bottom end can still run.  They knock like a son of a bitch and will run until the bottom end completely blows apart.  If there was very little oil then you must have a leak someplace and that could have caused this ? Check the oil plug and any seals as well as any oily places on the engine. 

Second item is the timing could have jumped and slammed the valves and piston together either putting a hole in the piston or bending a valve. 

Third item is the compression release has failed and that’s all it could be ? 

Based on the low compression I would feel theres a hole in the piston or a big crack somewhere or a blown head gasket.   

Pull the oil cap off, put the spark plug back in. Do not put the spark plug wire on! Crank the engine and see if you have air pressure coming from where  the oil fill cap is by holding your hand lightly over it. If so you def have compression leaking into the engine. 

You can also spray the engine down with a soapy water solution and crank the engine and look for bubbles. 

I would do these simple tests first and go from there.  

Hope this helps.  

 

 

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