Mhatayas

I've since switched to another carb,I've read online a lot of people switched to smaller carbs due to flooding issues. This worked for me . Switched from the original vm34 to a vm32 from my 85 2wd bike. It was running perfectly, UNTIL, get this : Bike runs for 15mins or so till it gets hot. Then it backfires a bit and makes popping noises through the carb. Then it spitters and cuts out like it don't wanna run . Let it sit for a bit to cool down then starts back up like nothing happened. don't know if this is a fuel pump issue or some sort of electrical or mechanical issue? Man I thought I finally had this bike ready to take on a run. Guess not

Hey folks, thanks for the responses. I've since gave up on the Chinese carb. Went back to the original fuel pump, drilled hole put valve in intake Boot etc.. still same troubles. I'm back to the regular OEM slider carb now, the original that is supposed to be on the bike. I got it from a friend, he's been using it on his ATV (same year and model as mine) for years with no issues. I put it on mine, it worked perfectly, for about 20mins riding. Then it started flooding when I would let off the throttle. It would sputter and sometimes almost cut out before it picked up again. But this is only after about 20mins of riding in 4th and 5th gear on a road throttle nearly wide Open. As soon as i let off, it seems it wants to sputter and flood out. I went and cleaned the carb inspection the needle and seat etc, cleaned tank replaced fuel petcock... New fuel filter. Still same issue. Do you think I should set the needle height a little lower? Or the float tab a little higher? The float tab is at about 35 degrees as it is . Is there some other type of issues I can be overlooking? Already tried adjusting the air fuel screw, still didn't make any difference. I should note, that the intake boot is from a newer model Suzuki lt4wd bike. It's a tad bit larger diameter than the old slider carb boots. That being said , I cut off about 1/2 inch of the boot, since there is an inner lip that's smaller diameter than the outside of the boot where the carb fits. The inner lip seals perfect with the older carb accompanied by a hose clamp. No leaks, sealed great, as well the rear boot is sealed great too. Don't think that could cause an issue would it ? I know it's a carb flooding issue because the overflow tube leaks gas when this happens, and it cut out once or twice and wouldn't start after that , plug soaked. Kind of boggled, since it was taken off the same type of bike working fine, and now doesent want to work properly on mine.

Ok. After a through carb clean I'm still having the same issue. Either too much or too little fuel depending on float tab setting. THERE IS NO IN BETWEEN!!! Seriously flustered with it all. It seems the needle/seat won't seat correctly. The vacuum port I drilled is up in the Intake manifold, used a presta valve from bicycle. Works well. Would it be too much pressure though? The carb seems to be spat out from the manifold at times with the back pressure? Is this possibly why the needle seat wont seat ? As much as I don't want to , I think I might just have to find another carb or buy one and use . Sucks . Wish I could take the rig for a run already.

Ok so , I got the float tab vent upwards near 45 degrees, and turns out there was a bit of crud in the needle seat. Ran good for 5mins of riding then it seemed like it starved itself for fuel. What should I do to the carb now , should I set needle height? I don't know yet if it's running lean or rich . I will have to get a new spark plug and check it out

Alls well there thankfilly! The fire was near the rear left tire, where the exhaust joins together. But today I figured something out snf why it's hard starting. Was running good for about 5min beforehand I setup a nibbi pe30 carb on my 87 quadrunner, paired with a low 1-2 psi electric fuel pump. Problem I'm having (i think) is the float needle/seat is not sealing properly and allowing fuel to pass it. whenever I turn on the key the pump keeps pumping fuel through and it overflow and leak through back of the carb. I tried adjusting the float tab to multiple different positions and it either would do one of the two , overflow or not flow enough fuel at all to let the bike run. Trying to figure out all potential issues here , fuel pump too high pressure causing fuel to force the needle/seat open and float not able to seal it on its own , or debris possible stuck in there ? Note that it worked good for about a minute before I noticed the bike bogging past half throttle, go to look at carb and it's leaking a constant trickle of fuel out the back . Any help is appreciated

Ok folks! After a new set of rings , installed with the gaps away from eachother, it seems, it's no longer smoking blue! Can't even see any exhaust! Very happy. But get this , I installed a Chinese nibbi pe30 carb, and electric fuel pump. The overflow hose on the carb is extremely long and just happened to drop fuel onto my exhaust during a backfire! You can guess what happened next. (This was right after the new rings installed and tested out. It did smoke blue for the first 30Seconds to a minute. But now no longer! ) In panic mode, I pushed the ATV out of my shed and pulled it out further into the snow where it wouldn't catch my shed on fire. I started throwing snow at it and luckily after a minute or so it went out . Phew, only burnt a bit of the overflow line off. I have up for the night and went back at it tomorrow. It seems the pull cord is too easy to pull over than it ever was, and it's hard to start with e start even. Though it idles and runs perfectly when it's going. I'm gonna change plugs anyhow because it's possible oil fouled . And the only problem now besides the starting issue, is anywhere past half throttle, it bogs and runs rough. Stutters. Seems like it's getting too much fuel or something. I May fiddle with the carb set the needle height, what do you think? It didn't do this at first when it was smoking blue . To confirm the smoke problem is gone , I added another quart of oil bringing the grand total up to 2l (still need another 1.5l Messenger_creation_92D48F5A-EE65-417F-89CE-B11688DE1340.mp4 Forgot to mention I'm going to do a compression test on it too now. But the main problem is thankfully solved !

yup swapped heads as well. one breather isnt hooked up for sure, one on the right transmission side just beneath the fender, dont know which hose is which. At this point mech, im just waiting till i get the new parts and testing the waters there, i pause the work on it for now before i get totally frustrated. Ill wit till next month . In other words, see ya in a months times LoL

Thanks ... The piston did slide up white nicely, and I used a cylinder and piston and rings from another bike that DIDNT SMOKE , so i knew it was good. I never gapped them or checked the gapa but everything honestly looked as it should. Cylinder still had crosshatch on the bottom half not so much up top, but it didn't smoke. When I put the parts from the bike that didn't smoke on the bike that did, the bike still smoke! If timing was off a little bit , would this cause smoke? It might be off by a tooth when I put it together.I'm sure valve guide seals are good because the other bike didn't smoke. I'l take it all apart AGAIN I guess. I am getting so frustrated with it at this point. This is my second plug that oil fouled by the way . No oil =no smoke , I drained it (the litre that was left in there ) and let the bike run and no blue smoke . Go figure. I got a new set of rings ordered anyhow

Correct, oil was halfway in the sight glass, none came out the filler cap, just burning it like crazy. Wonder if i didn't install the rings correctly? i tried to make sure the gaps weren't lined up with each other. This is so frustrating and annoying

Just to make sure we are on the same Page mech, im not talking about my 2wd chain driven lt250 im talking about the LT4WD bike i recently obtained. with the high low and super low 15gear transmission.

Possible that carborator i have, the diagphram that isnt meant for the engine causing this ? i dont understand. I have a nibbipe30 carb and electric fuel pump ordered for it anyway, so ill be selling these oem carbs when i get the chance. I was dumb and gave away the old slider carb i had for it

Yup thats the spot, hard to get to, says 3500ML right next to it. I filled it until i seen it in the sight glass, ran it for a bit and filled again till i seen it was between the two marks in sight glass. it burnt so much oil in juat a tank of gas there was just about a litre left, as well didnt stop smoking till there was practically none left in there..

Says 3500ml . I filled it until the oil was between the marks on the sight glass When I took the top off a bit of oil poured out. There's oil in the combustion chamber since I see it on the spark plug. If I flush the engine with Diesel or kerosene think that'll help me ?

So I noticed there is no crankcase vent hose, does the hose that's supposed to run there go to the air box or up under the dash ? I'm talking about the one on the right side crankcase just beneath the fender

What about the oil pump? would that have any effect on it i wonder, maybe something is clogged? would the oil pump be a component that would just stop working properly?

I drained the oil, only about a litre came out, i then let it run for a minuite or so, no smoke. I added 3 litres when i added the oil to it in the first place, but it burnt off all that oil (~2l) in just about a tank of gas! i only rode it for a few hours in total. what do you think i should do next? add oil and see what happens? or add some sorta cleaner in there and let it run for a bit before adding oil. do you think there is an o ring or something letting oil go in where its not supposed to? what about #10 on that same diagram? before i even drained the oil, it wasnt even visible in the sight glass! I need to get a new oil filter before anything though! thing is toast

Looks like the oil seal is just beneath the magneto, not as big of a job as I expected. Gonna have to order a new one, though!

Mech, is it possible some of the breather hoses not being hooked up would cause it to burn oil? or not so much? the only other possible thing i can see, is the crankshaft oil seal itself (see #17 on this parts diagram) , unless some other O ring or something https://www.suzukipartshouse.com/oemparts/a/suz/50d0b06af870022c2c53619a/crankshaft

When tilted on its side, i looked into the sight glass and seen black oil. I am pretty certain there is no fuel getting in there. So you mentioned i shouldn't see oil in the crankshaft area like i did when trying to find the timing mark? i looked at the parts diagram and there is some o rings and the such on the end of the crankshaft. do you think one of these could be worn away and letting oil in where its not supposed to? another thing to mention, i didnt change over the piston or rings or cylinder head because it all looked good, though there was only crosshatch on the bottom portion, there was some straight lines where the piston strokes. I already got it half apart again and im going to switch over piston and cylinder from the bike that didn't smoke, just to be sure. the rings looked great on the original though... compression was good, 110 psi.. there are also other various o rings and seals amongst the crankcase and oil sump and clutch etc.. do you think one of those could be a culprit? i haven't seen any cases elsewhere of that though, from research. tommorow im gonna try to switch to the other pistons and rings, and cylinder etc, if that doesent work, then i will go ahead and assume its something else

So I tilted the bike 45° on its right side, and started it up for a few mins, no blue smoke , just a bit of exhaust smoke. When I put it back on the flat it started smoking blue shortly after.

So I got it all put back together! It was running good for a few mins, then started smoking again... I looked at the oil sight glass, and appears there is no oil in the sight glass! I'm thinking it just might be what you mentioned Mech, oil getting spat up through the crank shaft. What are my next steps? Its good I was at least able to rule that out. Should I drain all the oil and re add it ? When I got the bike I didn't drain the oil just added some. Is there a way the oil is seeping in there where it shouldn't be?

What do you mean by fuel tap playing up ? The petcock at a certain position? As for the oil, I filled it up between the marks on the sight glass, let it run , filled it up to marks again, then once it stayed between the marks I left it . I haven't checked it over the last month or so , but I will tomorrow. It was smoking before that though. I should have clarified, I used a tissue stuffed into the sight hole for the timing mark and cranked over to clean off the residue, but after every rotation it seems to be picking up oil again on the bottom half of rotation. I'll get a pan and drain it tomorrow and re add it to spec after I'm done. Do I have to take off the starter and crank the nut to do that ? I know it suggests that in the manual, I got it going slow enough each revolution from slowly pulling the pull cord, it's just the oil made me unable to see the mark I seen some guys on a quadrunner group in Facebook got a nibbi pe30 carb and low psi electric fuel pump, I have these two items ordered for my quadrunner, no vacuum this way , apparently they are really good carbs and work very well in that setup.

Folks, I've since took the cylinder head off another 2wd quadrunner I have, that ran without smoking before I took it apart. Upon inspection, the rings and piston looked great on the 4wd. Today, I was in the process of putting the cylinder head from the 2wd on, but I'm slightly stuck on getting the timing chain alignment correct. The part I'm stuck on , is the finding and lining up the "T" mark. I crank it over ever so slowly with the pull cord paying close attention waiting for the T and the little line to show up. But upon doing that , multiple times all I see are round depressions, plus the rotor always brings oil back up making it hard to see. For reference, my quad is an 87. Would it be easier if I tried to shine some light down the spark plug hole and crank it till I see the piston at TDC (top dead center) or even shoving a wire down there and feeling it to TDC ? Or would I be better off draining the oil and using a paper towel to soak up the bit on the rotor and try it by lining up the marks ?

That's what I'll do next , check the vacuum line for any leaks . I also tried using the throttle adjustment screw, it worked good idling while running, but seems my throttle is a bit sticky or something, it would remain revving for a bit after throttling sometimes. I got this excerpt from the Suzuki manual: "If the plug exhibits a black insu lator tip. a damp and oily film over the firing end and a carbon layer over the entire nose, it is oil fouled. An oil fouled plug can be cleaned, but it is better to replace it" (The gap was also bridged with this substance on mine. ) I also read that an d7ea is hotter than a d8ea plug , which means if using engine at high rpms and temps, to use a colder plug , looks like I will switch to a d8ea from here on. My 4valve lt250ef has this plug

So, I figured out the problem, it was an oil fouled plug. I pulled off the plug and it was just saturated in black. Oil and even looked chunky and sticky. I ended up just using one from another ATV instead of cleaning it . With that being said , I now have the bike parked until I can fix it up. I ordered a set of rings (company called tp) from eBay today, and also valve seals. I'm gonna order a head gasket as well when I get the chance next week. This should at least cure the smoke problem, I'll also check if valves need adjustments when I pull the head off. So here's something funny though, battery is fully charged, and it was -5°c today, wouldn't start no matter how much choke or how long I pressed the start button. I hook my battery charger to the battery and put it to 20amps and crank it over it eventually catches and starts. A few weeks ago when got the bike up and running first of all , it would start effortlessly. Just press the button without using the choke. Do you think this may be to do with the cold weather? I'm not sure what is going on here, but I don't like it .