Quantcast
Jump to content

  • Join Today, It's Simple and FREE!

    As a member, you can post in our forums, upload your photos and videos, use and contribute to our downloads, create your own member page, add your ATV events, and even start your own ATV club to host your own club forum and gallery.  Registration is fast and you can even login with social network accounts to sync your profiles and content.

Azrack

86 yfm225 won't start

Recommended Posts

Hello new to the forums. Just picked up a 86 moto4 yfm225. When I got it the engine was partially seized I did the bp blaster for a few days and it turns over great now. I get plenty of spark and wet plug but it won't start. I checked the valve clearances and timing both correct and I cleaned the carb. Occasionally it will catch and backfire through the carb but that's the best I can get. I would greatly appreciate any ideas anyone has.

Thanks

Az

Share this post


Link to post
Share on other sites


So figured it out. The intake valve was stuck when I checked the valve lash it looked right but I think the previous owner set it to the stuck position. I got the valve free with more pb blaster and found out the hard way the intake rocker arm broke from the over zealous setting. New head otw (cheaper then a single arm ) guess use the time to check the cylinder wall and piston.

Share this post


Link to post
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.
Note: Your post will require moderator approval before it will be visible.

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 Topics

    • By Daniel Gibson
      Working on a bayou 220 that has been ran extremely hard it's whole life. Literally had almost an inch thick dirt/oil covering the motor. Yeah that bad. Surprisingly it runs though. I cleaned the carb and tank multiple times. They're clean enough to eat off of. Readjusted valve lash and set timing. Was about 3 teeth off. It cranks good and runs good only problem is I have to cover the carb intake basically choking the hell out of it for it to start. The com choke works fine. It does this each time I start it regardless of temperature both ambient or motor. Wth? Compression is at 115psi I get 130s if I put a little oil in the piston chamber. Please help. Thanks 
    • By Dwight Williams
      Hey everyone, I've been scratching my head over this for most of the day.  I bought a couple of Bayou 220's, got them running (they've both been sitting), and started tweaking and fixing small things.  One of them is mostly done, the other had an aftermarket carb on it and I've been trying to sort that out.
       
      Anyway, while adjusting the carb it died a few times, I restarted and moved on until it died and wouldn't restart.  I figured maybe I'd flooded it or something - after further attempts I realized I had no spark.  Since I have two identical machines I have many parts at my disposal.  I've swapped the CDI, spark plug and coil with no luck.  I have good resistance readings from the stator and pick up (135 and 110 respectively),  I don't have a peak voltage meter but I measure around 53VAC on the stator when cranking.  I have a 4 wire stator, not an alternator like the newer ones.  Grounds look good, I've checked the kill switch by verifying that it and the ignition switch grounds the black/yellow wire to the CDI.  I can turn the engine slowly and see the pickup short the meter as well, seems normal right?  So far everything I've checked looks the same on both machines.  I've got the service manual and wiring diagrams.  Do these readings make any sense?  I'm obviously missing something but I'm stumped.  thanks!
    • By Dwight Williams
      Ok, so I bought a 2006 bayou 250 for 200 bucks, kid couldn't start it and had no idea why it wouldn't run, I pulled the rope and felt what I thought was valve to piston contact, he wanted 500 and I talked him down to 200 and brought it home.  Sure enough, timing was way far out, timing chain incredibly loose.  So for fun I re-tensioned the timing chain and re timed it, got about 120lbs of compression, pretty low.  I cannot get the chain very tight but the the tensioner seems to work fine, the chain guides don't look very worn.  Also, when I took the head off the valves don't look bent and the piston has no discernible marks on it.  Is this an interference engine?  I sure thought I felt some contact with the pull rope but maybe no permanent damage was done?  Anyway, I plan on doing a full top end job as well as timing chain tensioners and hopefully that'll cure it.  Is there any reason other than chain stretch (I measured it and it's ok) or guide wear that would cause the chain to be so loose?  Thanks!
       
    • By Mike Johnson
      Does anyone know what the 3rd item is behind the battery on this ATV ? I know 1 is the,  solenoid1 is the CDI box, what is the 3rd.
    • By JC4x4
      My Honda Fourtrax won't start. The starter is kicking the engine over, but it won't start. It sat for about a year while I was living away, so I thought it might have been bad gas. I completely drained the fuel, flushed the fuel lines and filled it with fresh gas. However, still nothing. It started and ran fine the last time I used it. Any suggestions on how to diagnose this? It could be fuel or electrical at this point. Is there an easy way to rule one or the other out? Thanks
  • Similar Tagged Content

    • By Christopher Williams
      Hello all, 
      i just rebuilt the top end of a 99 Bear Tracker 250 and it can’t get it to hit off of gasoline or starter fluid. Occasionally it will backfire. Right now I’m just trying to get it to fire off without the carburetor like I’ve done a thousand times before with other engines. Usually there is no response, but occasionally I get a backfire through the intake. ISeems like it’s out of time, but I don’t see how that could be possible. 
      Here’s what I know:
      1. compression 120psi
      2. all timing marks are lined up after numerous revolutions. 
      3. Strong spark. 
      4. Valves adjusted correctly. 
      Thanks in advance. 
    • By Michael Taralli
      My 2006 Prairre will only start with a shot of starting fluid. Any ideas or suggestions of what might be the problem?? Thanks.
    • By BeardedBackWoods
      We have a 2wd Bear Tracker that was flooded out by a tornado and I've since been trying to get it right. I've cleared the water out of the tank and now has fresh fuel, and I've opened the carb so many times I could do it blind folded under 10min. She'll fire up as soon as you turn the key and hit the button, even on a cold start, and idles perfectly. But the second you hit the gas it bogs down and dies. I had it running GREAT for about 10-15min once and suddenly ran like shit and limped it back to the house. I've barely got it to move under its own power since. I'm at a loss at this point. Does ANYONE know of something stupid I could've missed? The carb does have a fresh rebuilt kit that I put on about a month before the flood. It was not started until it dried, I cleared the tank and opened the carb the first time. I guess I'm just gonna pull the entire thing apart again and go from there. Maybe another rebuild kit? I'm gonna swear this thing is clean though. 
      Thanks for any ideas
    • By alexcross324
      Hi all, I try to find this manual in the threads but you have a lot of stock here
      Cannot find this particular manual.
      I found it for YFM200 but not sure if they are the same.
      Thanks if you could help me with that.
      Im new here so if I did something wrong, please tell me.
  • Recently Browsing   0 members

    No registered users viewing this page.


×
×
  • Create New...