91 Suzuki Kingquad 300 low compression, wont start

[bsfs1988]

Hey guys hope everyone is well. I need sum advice or help. Anyways I already rebuilt the carb however I noticed that the carb is spitting sum gas towards the airbox and i did a compression test and i only got 50lbs what should the compression be for these lil monsters bc 50 lbs isn't a lot I figure it will b around 100lb or so. So I'm thinkn a piston,bad valves? it does smoke white but I can get it to run but hard to start and I got to keep the slide all the way open on the carb to get it to even run but once I let the slide down it cuts off so its not even driveable right now plz help me guys trying to get it running b4 we get snow

[oxidized_black]

should be between 120-130 lbs ...

[bsfs1988]

Thanks ox I knew it was to low. so what u think bad piston rings or bad valve? It is spitting a lil gas out towards airbox, so I'm guessing air is sumhow getting out and pushing sum gas out of carb.

[CK1999_400ex]

valves and timing can also be the prob... i would check and see how tight the valves are adjusted ... if you have a service manual on it ...it will tell you how to do this ... and you can also check the timing that way ... it almost sounds like the timing chain might have jumped 1 tooth ..

[oxidized_black]

nice work ck... was waiting for you to comment on this

[James_P]

you mite want to think about buying a new timing chain and doing a head rebuild/cleaning.

[bsfs1988]

Thanks guys unfortunately I dnt have a book so I dnt know how to check timing and valves I'm pretty much doin this with out a book and mainly guess wrk. It does have around 5k miles on her and the recent owner didn't maintain it very well. Any tips on how to check that stuff. If I have to break it down anyone know where I can get a good performance cam for it and get it bored to next size hopefully that will give me sum extra power

[bsfs1988]

Also how do u put motor on tdc and how do u know when its on tdc as I know it has to be on tdc to set/check valves

[cheriah]

line up the mark on the crankcase to the mark on the flywheel=TDC:wink:

[bsfs1988]

So I need to take the valve cover off to line it up or? I kno how to put tdc on a car but not familiar with atvs. Thanks in advance

[bsfs1988]

So today I set my valves however still a no go. I set intake at .004 and exhaust at .006 now I'm geting backfire thru the carb and cnt get it to start at all also put a new plug in. Any other ideas guys? And yes it was on tdc

[James_P]

my bayou 300 needs a good battery to run, i guess it needs the extra power

you mite want to check that.

[James_P]

i had the same trouble with my bayou

[bsfs1988]

So I set my valves again and it cranked up first time it ran about 2 mins then cut off I got valves set int .004 exhaust .005 I put it on tdc by taking plug out and feeling for air then use the hand starter to put piston on top I got needle jet about 2.5 turns out should I turn it in some so I can get it to idle. And got new spark plug gapped at .26 any tips guys or ideas what I should do or check

[oxidized_black]

why did it shut down? fuel? or spark? can you tell?

[bsfs1988]

What's up ox. Naw I dnt know y it shut off. When I reset the valves she cranked as soon as I turned it over. I do have my air mix screw turned all the way in til I can get it to idle and get it set however when it did crank it didn't idle high with the air mixture all the way in which it shud have. I'm thinking its fuel problem bc when I took old plug out it was extremely black and had residue on it as well so burning rich right?. I got the needle jet set at 2.5 turns out frm seated. It's almost bck to same problem it will crank if I raise the slider half way up to give it more air

[bsfs1988]

I just thought about sumthn the needle that goes in the slide which way does it go in? Do the grooves and clip need to b up or down? I think this is my problem its to cold and dark to mess with it right now so I'm gonna try it tomm

[bsfs1988]

Got it started today however soon as I give it gas she dies but it will idle pretty decent any ideas?

[bsfs1988]

I got it to idle and kinda wnts to bog when I give it gas then after playing with it a while I can give it gas however when I give it full throttle for about a min she will cut off and I noticed the float bowl is completely dry! Any ideas ? Bad float or bad float spacing or sumthn

[bsfs1988]

Checked compression its at 95psi now so better then b4. bout to check timing shortly gotta figure out how to check that I got plastic off I kno how to line cam gear but not crankshaft part I'm sure its simple

[Thayer40]

Could be bad fuel lines or fuel filter/pump. Pilot screw setting might be closed too. And your going to want the valves a 6 thousandths and maybe even 7 thousandths for the exhaust valve because it will expand a little with the heat.

And make sure you run premium fuel in there because anything else is terrible on the carbs

Edited February 6, 2012 by Thayer40

[quad_king_300]

you need atleast 3 turn out for idle. the smaller 250cc needed 2.5 out. use the choke to start and then shut off. you might have a clogged jet clean it with a single wire from a steel wire brush.

[bsfs1988]

I hvnt had much time but i did put a new float in it. Still bog when I give it full throttle but Idles good my book said pilot needs to be 2.5 out but il try 3 and readjust valves again il let u kno what happens when I get a chance to mess with it