Quantcast
Jump to content

Honda 400ex WONT START HELP


Wali

Recommended Posts

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 

Link to comment
Share on other sites

  • Ajmboy changed the title to Need help Honda 400ex No Start

This could be one of so many things.  Engines that blow the bottom end can still run.  They knock like a son of a bi*** 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.  

 

 

  • Like 1
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Similar Forum Topics

    • By Gwbarm
      Just aquired this Honda 4514. I had heard of them and seen them but had never really looked at one. Amazing machine from the 90s.
      It has a 14 HP inline 2 cylinder engine. A cute little fan like the old school cars had and a little radiator. It has a timing belt on the back of the engine running the cam and a water pump. Just like a miniature car engine with  electronic clutches to turn blades on and off. Pretty hight tech for the 90s not a small thing and built like a tank weighs in at 600 pds hydrostatic trans. I have found out that almost anything you have to do to it the engine has to come out starter timing belt water pump. Very expensive parts i think most got junked for that reason, i did find out they were built by John Deere except for the honda engine.
      Does anyone here have any expierience with these. 
    • By 1998Zuki250
      What are your riding location preferences? Mud Park? Personal Trails? Public Land?
    • By 88Tecate4pal
      Anyone have an assembly? Thumb throttle and cable to carburetor?
    • By lewisrssll
      View File How To Perform Compression Test
      How to perform compresion test
      Submitter lewisrssll Submitted 10/06/2024 Category Other ATV  
    • Fast Free Shipping on All Orders Over $50
    • By Chucksta
      So.. it a weird one.. The quad surges as you go down the road. By the looks of my tracks, it's one wheel only. High range, low range, 2 wd , 4 wd.. It just doesn't matter.. 
      You can see in the pictures the marks it leaves. That was in a straight line, with hardly any acceleration. 
      Any ideas?



×
×
  • Create New...