Quantcast
Jump to content

  • Do you own an ATV? Join our Forum!

    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.

Steve Howard

1997 Polaris Magnum 425 4X4 back fireing through the carburetor

Recommended Posts

Ran find shut down the quad next day would start and idle when you try to accelerate it would start popping through the carb got a rebuild kit soaked it in chem clean after break down for 12 hours on slow vibrate reassembled and adjusted per manual still the same thing any help would be really appreciated thanks and happy ridding  

Share this post


Link to post
Share on other sites


Only other thing I can think of is the throttle controller.  Are there two wires coming from that throttle ?  You would have to take the two screws off of the top of the throttle on the handle bars and see.  

I think that bike is to early to have the rev limiter on it but let me know.   

Share this post


Link to post
Share on other sites


On the throttle in the handlebars ? If so open it up and see what’s going on with the wires. I believe it’s a normally open circuit. It may be bad.  There is a plastic partition that separates the two contacts.   Sometimes that falls apart or water is inside the throttle compartment.  Separate the wires or disconnect them and see how it runs.  

Share this post


Link to post
Share on other sites

I took the cover off everything is clean and dry? I disconnected the wires from the throttle lever and still the same starts right up but wont accelerate  

Share this post


Link to post
Share on other sites

Ok good so that eliminates that.  I think your next move is back to the fuel.  I know you soaked/vibrated the carburetor good but sometimes the clogs are not as easy as soaking and if something got wedged in like a small piece of dirt or rust.    You may want to take that carb off and take a pice of wire and clean all the jets and ports out good.  I like to take a piece of brake cable from a bike and separate the strands and use one of the strands. It fits right in the little holes. Blow it out with air and re assemble.   

Make sure the float is good and set right and not closing to early.

Double check the gas petcock on the tank and make sure it’s clear and free flowing.  

This will eliminate any fuel delivery problems or questions. Put a fresh plug in and see what happens. 

If this clears it up great  if not you have to start looking at spark issues  or a breakdown in the ignition system. 

Double check that your kill switch is not faulty and shorting or a loose contact or full of water.  

Share this post


Link to post
Share on other sites


You can double check the wiring all the way back to see if there is a bust in the wires. 

Have you tested the spark for any breakdown.   I purchased an in line spark tester after another member pointed  me in the direction of the rev limiter and found my spark was breaking down due to the rev limiter having a fault but my problem was in the handlebars at the throttle.  I separated the wires and it ran fine.

Share this post


Link to post
Share on other sites

I bought a inline spark tester and checked the quad not loosing spark I can hod my hand lightly over the carburetor and I can get it up to about a 1/4 throttle and it starts popping through the carb real bad Thanks 

Share this post


Link to post
Share on other sites

Have you checked the boot connecting the carburetor to the engine for any cracks or leaks ? If you have good spark then I’m leaning toward a fuel problem.   It’s sounds like you did the right job on the carburetor but covering the intake starving the engine for air allows it to rev then it appears it’s within the carburetor. Is that bike gravity fed from the gas tank or a fuel pump ? 

 

The only other item I can take a guess at is the gap between the flywheel and pick up coil.  Take a look and see if that gap is within speck.  Double check the pick up coil is tight and all is ok inside that cover.   

Share this post


Link to post
Share on other sites

Get a can of carb cleaner. As you give it gas, give it a little shot of carb cleaner through the intake hole and see this extra fuel makes it rev. If it does, then you know you have a fuel starvation problem.

Share this post


Link to post
Share on other sites


Welcome back

I don't think it would be the cam, maybe its time to start going over the testable electrical parts. Regulator, stator coil and pick up coil.  
If you have the manual its stated what the readings should be as well as the process. We can also help you along, its not hard to do and all you need is a multi meter.  

Share this post


Link to post
Share on other sites

Absolutely could be a cam problem. Polaris had big problems with cams wearing out in short order back then. They fixed the problem I think in 2001. But do the test I mentioned above first and report back the results.

Share this post


Link to post
Share on other sites

I would agree with @BuggyMasters if it was a problem that slowly got worse. BUT for the atv to be running fine one day and the next day have this problem?  Polaris did have a cam issue but it showed up over time, not over night.  Spark plugs started to foul and the backfiring once in a while.   I just don't see it happening over night.  

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 amharrison24
      i have a 91 moto 4 100. has electric start only. for as long as i could remember we have always pushed start it. after riding for while you shut it off. you are able to hit the start button and it will start right up. anyone know where i should start with fixing this issue? im fixing it up for my niece. thank you in advance.
    • By Dra O
      posted a while back - it was running at one point - I have all the plastic shroud off - it's down to frame and engine now
      -fuel pump: when line from petcock is attached, no fuel comes out other side to carb; the line to the carb is open (can blow through it); I thought when I cranked engine that the pump would spit out fuel on other side but it does not; I removed fuel pump and opened it up - diaphragm looks good - but internal areas had lotsa calcification build up - I cleaned this out and dried it good - the clear plastic pieces (?diaphragms) aren't broken - the spring w/ steel ball on end moves freely; am putting it back on tomorrow; but can anyone answer about the pump? isn't it supposed to pump fuel through it... to other side... to carb? puzzling
      -along with fuel pump: I replaced petcock 3 weeks ago (gas tank had rusty fuel in bottom - cleaned it out prior to new petcock); when I turn petcock arrow NOT to on or reserve, fuel comes out of line; when I turn it to on or reserve, fuel doesn't come out; puzzling
      -I don't know what's on back of fuel pump - it's a valve that has a hose coming out of it - looks like it goes to engine/carb - I haven't traced this out yet - what is it?
      -can squirt gas on air filter and engine will run for 2-3 seconds then stop - fuel in top of carb (under diaphragm) does same
      -it likely needs carb rebuild - will get to this - but something isn't allowing fuel to get from fuel pump to carb
      -I THINK it has a mikuni model x carb - diaphragm is ID 26mm  OD 68mm - hard to find inexpensive diaphragm, I guess because it's a model x
      -last thing - I replaced solenoid due to old one clicking; I HAVE to be charging the battery or it won't start/turn over - battery just goes dead; but if charging, it'll turn over nicely; i'm guessing it's a bad battery
      -any help appreciated - I've never owned an ATV before - inherited this beast from grandparent in-law
    • By Steven Urban
      First time using this forum.  Owned a Kawasaki dirt bike once, had no issues.  But I picked up this 4 wheeler at an auction.  They stated it ran, but only needed a battery.  Well I do not believe that was all true.

      Some pictures are attached.  Not sure why, but the whole air filter stuff was removed.  They had some small thing inserted as a make shift air filter.

      I purchased a battery to try this all out.  Waiting to return it and get the proper size, as it was too big for the battery box.  But here is my issue I had while the battery was connected.

      1 - The lights on the steering column did not come on.  Not sure if they work or not.

      2 - The starter solenoid seems to be bad.  I have a new one on order. 

      3 - In the pick, there is another rusted part.  Not sure what that part is or what it is used for.

      4 - What is the 12v rectifier?  square bodied part.

      So when I hooked the battery up.  Pushing the start button did nothing.  Pulling the cord to try and pull start, it turned, but would never fire.  I have put in a new spark plug as well, it looked worn out.  With electric start, I crossed over the posts on the start solenoid, it turned over, but would never fire and start.

      I have read a few other threads and it stated something about needed the neutral light on.  SOmething about a kill switch.

      Any help would be appreciated.



    • By Ed Zeppeli
      Hi,
      Oddly I'm having  a hard time ordering front brake shoes for my '98. 
      I'd appreciate recommendations on decent, widely available shoes if possible. Ideally available in Canada on short notice.
       
      Thanks much,
       
      Warren
  • Recently Browsing   0 members

    No registered users viewing this page.


×
×
  • Create New...