1996 Suzuki King Quad 300 Smokes [VIDEO]

[crochet homemade]

I have bought a 1996 suzuki king quad 300 and I have noticed that it smokes but I have put oil in it and plenty of gas had to fix shifter bc the nuts and bolts came out somewhere. I have had to replace the wire for the starter but now when I try to start it it wont idle at all and when it does run it smokes really bad like a whitish blue I guess, and it likes to stall a lot. So anybody can help me out please and thank you

[flyinbrian365]

The top end is going to need rebuild it's burning oil. You'll need to have it bored and go through the valve terrain. Also would be a good time to rebuild the carburetor.

[Tim-ANC]

Agree with Brian. Before you pull the top end apart, check the timing to be sure the chain hasn't jumped. If it has, might be a stretched chain or tensioner problem.

[Frank Angerano]

What’s happening is most likely your valve seals are bad and maybe your rings are going as well.   The valve seals are bad allowing oil to get into the head and is prob fouling the spark plug as well. The spark plug should be a dark black color with this condition. 

Take a compression reading first and see what you have. Then order a new set of valve seals and gaskets.  I would replace the rings as well.  This should solve the problem.  The piston is probably fine but while your in there might as well. I know some people don’t want to spend the extra few bucks but it’s worth it if the bike is in good condition.  

A good cleaning of the carburetor would be good since it’s going to come off the bike anyway during this process.   

[Mudrecon]

I guess I'm in the same boat

 

Edited May 11, 2019 by Mudrecon

[Frank Angerano]

Possibly, just keep in mind it could be just the valve seal.  I always like to proceed with caution on my work.  If the valves can be exposed and you can see the seals then you can crank the engine and take a Q tip, make up a good soapy solution with dish soap. Dab it around the valve seals. You will see bubbles around the rubber seal as you crank it. You don’t need a lot of soapy water. Just enough to coat the rubber. Any bubbles then it’s a bad set of seals. Change them all and change the oil after ward.  

[Mudrecon]

I'll try that Frank - I use the soap test for so many things. A 50/50 mix with water in a sprayer knocks down hornets, wasps etc . Not just a mechanics tool

 

[David Peterson]

Frank has a good idea of checking the valve seals. I had a Suzuki quad 300 that would smoke at times. The compression checked out good, leak down test showed acceptable. Spark plug showed good as well. What I found was the exhaust valve guide was worn just enough to let some oil get passed it and get sucked into the exhaust port. The heat from the exhaust burned the oil in the exhaust pipe. Found the exhaust port wet with oil.  The exhaust valve is covered in oil on the head when running.  By the time you replace the valve and valve guide and seal. You could have bought a good used complete head cheaper. 

So look at your spark plug, if it has oil do a compression test and leak down test.  If all of those are ok, remove the exhaust pipe and look for it to be wet with oil. 

[Andrzej Polak]

do a compression test

[My kiwi shed]

I think I might have a similar problem except mine only smokes if you start revving when it's cold. If left to warm up properly it generally doesn't smoke. Stuck ring?

[Frank Angerano]

That all depends on the color of the smoke.   If it’s black smoke then it’s just the choke and a cold engine.  If it’s a stuck ring which would be unlikely and more so valve seals then the smoke would blueish.   

Basically oil is seeping through the valve seal and making it’s way into the cylinder head and burning off when you fire it up. 

 

 

[My kiwi shed]

Yes white/ blue. Thanks frank

[Frank Angerano]

👍🏻

[Michelle Hodges]

I have a similar problem to one that was posted I have a 96 King Quad it's smokes really bad when I started up and then when I turn it off it smells like burnt gas for like 5 days it idles just fine though. Would that also mean the top-end needs to be redone Rings seals but what about the smell of gas I just replaced the diaphragm cuz it was bad

[Michelle Hodges]

 all of your comments have been extremely helpful. 

[Frank Angerano]

Could be a number of things. But first you have to identify what color smoke then pull the spark plug to see the color and also do a compression test.  
Black smoke rich fuel condition caused by a stuck choke of a dirty/improper adjusted carburetor. 
Blue smoke is oil from either bad valve seals or worn piston/rings.   
 

[Michelle Hodges]

15 minutes ago, Frank Angerano said:

Could be a number of things. But first you have to identify what color smoke then pull the spark plug to see the color and also do a compression test.  
Black smoke rich fuel condition caused by a stuck choke of a dirty/improper adjusted carburetor. 
Blue smoke is oil from either bad valve seals or worn piston/rings.   
 

Thank you

[Frank Angerano]

Your welcome.  Let us know what you find.