gunner6262 Posted May 25, 2010 Report Share Posted May 25, 2010 so i started my she today after doing a rebuild and it was running ok and i was blippin the throttle alittle bit and letting it idle and warm up. the engine was running good and then exhaust started coming out one side. so one side was cool and one side was warm. i was still blipping the throttle seing what was going on and then the last time i did it the throttle came down alittle bit and then ran at a constant idle like it was dieseling. waaaaaaaaaa...... i hit the kill switch and open the carbs and it died luckily. so whats going on here? is the one side getting saturated with gas and causing a dieseling effect? that would explain why its only firing on one side. there are no air leaks i did a leak down test. pilot screws out .5 turns. carbs synced. its a fresh rebuild .080 over with +4 timing 28mm pwks fmfs coolhead. Quote Link to comment Share on other sites More sharing options...
AKheathen Posted May 25, 2010 Report Share Posted May 25, 2010 well, that is a sure sign air is getting past and leaning it out. make sure the little choke tube is in place, and that the carbs aren't glazeed where they seal to the intakes. if the air screws need that much fuel, either the pilot is too big, or there is a leak Quote Link to comment Share on other sites More sharing options...
Rsbanshee Posted May 25, 2010 Report Share Posted May 25, 2010 so it didnt do it before the rebuild? if ur sure there arent any air leaks i would go a little richer on the pilots. mine was doing the same thing although i have stock carbs so urs may act differently. i ran my air screws all the way in and it did better, so i went with a size bigger pilot and now its perfect. Quote Link to comment Share on other sites More sharing options...
gunner6262 Posted May 25, 2010 Author Report Share Posted May 25, 2010 so it didnt do it before the rebuild? if ur sure there arent any air leaks i would go a little richer on the pilots. mine was doing the same thing although i have stock carbs so urs may act differently. i ran my air screws all the way in and it did better, so i went with a size bigger pilot and now its perfect. not stock carbs so no choke tube. and everything is sealed i mean its a tight sealed case for sure. the leadown test lost no air so i dunno how it could be an air leak but i think im running to rich maybe i'll back out on the air screws and see what that does. i know dieseling is usually caused by an air leak but air leak is ruled out. so i was seeing what else would cause it. and is it true dieseling? i mean i hit the kill switch and opened the throttle and it died. if it was dieseling then that wouldnt stop it correct? Quote Link to comment Share on other sites More sharing options...
jbooker82 Posted May 25, 2010 Report Share Posted May 25, 2010 Are you sure it was actually dieseling. I have had a broken reed before. The one side got cold. Had a lazy idle like it was dieseling. It was pulling air in though the exhaust pipe on the cylinder that had the broken reed. I would think that if it actually was dieseling / preignition it would be extremely hot and have a run away engine. Quote Link to comment Share on other sites More sharing options...
gunner6262 Posted May 25, 2010 Author Report Share Posted May 25, 2010 Are you sure it was actually dieseling. I have had a broken reed before. The one side got cold. Had a lazy idle like it was dieseling. It was pulling air in though the exhaust pipe on the cylinder that had the broken reed. I would think that if it actually was dieseling / preignition it would be extremely hot and have a run away engine. that makes more sense thank you. i have checked the reeds and they arent broken or cracked. im gonna say the problem would have to lie within the carbs. im gonna work on it today. but in case it isnt the carbs i would defintely like ideas. so yeah if it was dieseling then it wouldnt of stoped like that right? Quote Link to comment Share on other sites More sharing options...
AKheathen Posted May 25, 2010 Report Share Posted May 25, 2010 the way to make a 2 stroke deisel is withe allot of heat. extra fuel actually keeps it cool. there are only 2 ways to stop it. either give it extra fuel, or physically stop it rotating. if it was too rich at idle, it would just lug down, aka loading up with fuel, and usually floods out.....however, i do agree it's probably just a carb tuning issue. likely that your idle is too high to begin with, but running lean. does the choke make it idle up alot higher when you start it? Quote Link to comment Share on other sites More sharing options...
Rsbanshee Posted May 25, 2010 Report Share Posted May 25, 2010 yea you can tell alot, as far as which way to jet, by using the choke and adjusting the air screws Quote Link to comment Share on other sites More sharing options...
gunner6262 Posted May 25, 2010 Author Report Share Posted May 25, 2010 the way to make a 2 stroke deisel is withe allot of heat. extra fuel actually keeps it cool. there are only 2 ways to stop it. either give it extra fuel, or physically stop it rotating. if it was too rich at idle, it would just lug down, aka loading up with fuel, and usually floods out.....however, i do agree it's probably just a carb tuning issue. likely that your idle is too high to begin with, but running lean. does the choke make it idle up alot higher when you start it? yup choke makes it idle high. Quote Link to comment Share on other sites More sharing options...
AKheathen Posted May 26, 2010 Report Share Posted May 26, 2010 go up on the pilot size, and bring the idle back down. it should only do that in the first 10 seconds or so when you start it cold. after that, it wwill just start loading up Quote Link to comment Share on other sites More sharing options...
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