1988 suzuki quadrunner 250cc 2x4 (LT-F250) not starting

[mmmPUDDIN]

I've had this machine for 2ish years, has ran great up until winter. Sometime during then, I managed to break the exhaust right before the muffler. The summer before it had a hard time idling, but we fixed it by cleaning the carb, and messing with idle. Near the end of last year, the only way for it to fire was the have full choke, and full throttle, and the engine bogged down and you had to keep on throttle for 25mins. Over winter, the throttle had dislocated, and I got it back in place. We got it running, and all was good. Spring came along, and now it doesn't start at all. A fluid is coming out of the exhaust, and I'm told it could be water from over winter. I checked the airbox, and the air filter isn't for this quad, it also is barely sucking air. There appears to be little to no compression, based on this. I'm pretty sure the engine is flooded, as the spark plug produces a spark, but is oxidized. I don't know how the previous owner treated it, or when it's last oil change was. A bolt on the engine has either oil or gas seeping through it,abd was loose. I tightened it and it consisted. The engine is basically positioned in the rear, and it needs a good clean, I don't have a pressure washer, so I can get the built on dirt off. any recommendations on how to get the beast started again?

Edited May 3, 2019 by mmmPUDDIN

[Cj Winds]

Fluid from the exhaust could be gasoline, did you replace any parts in the carb? If not, buy a rebuild kit, they can be found on ebay for under $30. The float on the carb is probably leaking and flooding the engine. Check the engine oil too see if it is too full, if its too full it might have gas in it. You will need to replace the engine oil and filter if the oil is mixed with gas.

[mmmPUDDIN]

On 5/5/2019 at 11:05 AM, Cj Winds said:

Fluid from the exhaust could be gasoline, did you replace any parts in the carb? If not, buy a rebuild kit, they can be found on ebay for under $30. The float on the carb is probably leaking and flooding the engine. Check the engine oil too see if it is too full, if its too full it might have gas in it. You will need to replace the engine oil and filter if the oil is mixed with gas.

I recently cleaned it, but didn't replace any parts. Again I don't know if the previous owner did, as I'm unfamiliar with this carb and engine. The oil doesn't look too high, but It could be mixed with gas, I will check 

[caperwing]

I had all the symptoms you have and adjusting the valves fixed mine. Oxidized plug sounds like water to me.

[mmmPUDDIN]

UPDATE: after more digging I found these possible sources for my problems: it could be a timing chain or a stuck valve causing the problem. It could also be the carbs float needing to be replaced, or a vacuum line getting fuel from a failed diaphragm (forget the name). Will keep you posted for updates

Attached video of me starting it in jan/feb

[David Peterson]

Suggestions. go back to basics. check the compression, spark, if the compression is not right the start there, find out why. Check the valve clearance's, check timing. if all that's not right it doesn't matter about everything else. 

One thing I have found through out the years on spark plugs is, if the item is a Japanese type import use nepond denso or NGK plugs only. Champion spark plugs don't play well in them.  Yet champion plays well in small lawn and garden equipment.  I had a Yamaha bike that had two spark plugs holes. Put brand new champions in it and it wouldn't run for nothing, put an old worn out ngk in it and it ran, Put a champion in one and ngk in the other and the ngk worked with out any problems, Champion didn't run at all. Tried more than one and from different vendors too. That is just one instance I've had among many, so that's why i say that about spark plugs.

If all that's good then move to the fuel side of things, Suzuki uses vacuum operated fuel pumps and in some a vacuum operated fuel petcocks. A leaking diaphragm in any of those can dump fuel straight into the engine. Making you think the carb is the issue. Clamp off the lines, check for fuel in the lines. I do see these items fail more than you think, more so on the older atvs. Trash getting to and into the fuel pumps kills the diaphragms. 

Once you get it to run, change the oil before you test ride it. the gas will damage the bearings and the centrifugal clutch. . Oil is cheap compared to the damage.

Hope some or all of this helps.

[mmmPUDDIN]

UPDATE: i working on replacing the carb, and changing the oil, as from it sitting the oil level is very diluted by gasoline. other sources say that all of my problems are most likely the carb being toast, as the problem wasnt sudden, it gradually had gotten worse the more it was used. will keep posted.