stuck valve?

6 replies to this topic
  • jessi971

Posted April 17, 2002 - 04:30 PM


I am having a problem with my 2001 426. I went to start it and did not feel like it was hitting T.D.C . It is like a valve is stuck or somthing. The compression realese is shut all the way. And it ran fine the night before, and now it wont start. Please help I am really confused thanks

  • John_Lorenz

Posted April 17, 2002 - 04:49 PM


I can not help with your confusion, I know a good shrink for that, But the Stuck valve it seems hat some one else had a simular issue "Loss Compression" Might want to do a search for that

Search for sudden loss you wil find a post from march 21 2002 it has some good info there that may help

sorry but try this, this is the Post
web page

[ April 17, 2002: Message edited by: EgoAhole ]

[ April 17, 2002: Message edited by: EgoAhole ]

  • Mark_Cantrell

Posted April 17, 2002 - 06:36 PM



blatham was an exception. There have been many reports on the 250F side of mysterious total loss of compression and mysterious return of compression. If you have already kicked it through several times, more times won't hurt it. Do odd things like tap the head with something wood or rubber or plastic. Put goat entralls over the valve cover at midnight. But keep kicking for a while.

I just lost compression, took off head, lightly lapped valves, cleaned concretion off of inside of exhaust valves, put together, and still very little compression. Ran it for a while and its back. Who knows?


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  • sirthumpalot

Posted April 18, 2002 - 12:54 AM


I had a similar problem with my '01. Started it, ran great. Let it idle for a moment or so and then shut it off to clean the carb. Shot some carb cleaner in it while it was still in the bike. Went to start it and it had 0 compression. I kept kicking and after about 6 or 8 kicks it fired and has been normal ever since. I have no idea what happened (stuck valve?). Try kicking it through a bunch of times and see if you can get it to come back to life. As Mark said, if you've already kicked it a bunch of times then anything that would have bent will already be bent so there should be no harm in kicking it a few more times.

  • Shawn_Mc

Posted April 18, 2002 - 07:31 AM


My 426 did the exact same thing. It just went away. If there is a tiny piece of crappola in the valve train, it will hold the valve open, or they can stick, especially after a wash. If it starts and runs ok, I wouldnt sweat it.

  • CAL

Posted April 22, 2002 - 12:47 PM


Whew! I'm glad to see this post. Mine just did the exact same thing this past Sat. Went to start it for the first time of the day...was trying to get to TDC and had no compression. Kicked it through slowly a few times...messed with the comp. release...turned it over some more and it had compression??? Bad part is I flooded the engine while turning it over so much. Put in a new plug, kicked about 40 times, and it started. After that it started first usual. Had me skeered there for a minute.

  • Boit

Posted April 22, 2002 - 07:56 PM


I also experienced th exact same phenomena with my YZ AND Stroker built KLX. With a few kicks on the start lever, they both built compression quickly. The only thing in common was that they both sat up a couple of week's time before starting. Whatever caused it was not permanent and neither has shown any signs of damage. In fact, the YZ is stronger than ever. The KLX is wearing valve stem seals rather quickly, though. This is attributable to the increased performance modifications done on this engine.

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