Cinese atv Zongshen 250cc fresh rebuild white smoking at idle and acceleration, help.

mikecombs66 · 05-17-2017, 02:05 PM

New fresh top end, new head,cylinder,piston,rings,head gasket, new ignition,fresh gas,fresh oil, starts and idles but white smoke puffing away at idle and reving the engine, I checked the spark plug, its black, cleaned it up and no help. Is it the new carb I put on with a bad mixture? could it be oil ? I have excellent compression. I was there when the mechanic double checked the rings and the clearance. What should I do? Its a Peace ATV with the ZONGSHEN 250cc

**JerryHawk250** · 05-17-2017, 02:24 PM

Quote:

Originally Posted by mikecombs66

New fresh top end, new head,cylinder,piston,rings,head gasket, new ignition,fresh gas,fresh oil, starts and idles but white smoke puffing away at idle and reving the engine, I checked the spark plug, its black, cleaned it up and no help. Is it the new carb I put on with a bad mixture? could it be oil ? I have excellent compression. I was there when the mechanic double checked the rings and the clearance. What should I do? Its a Peace ATV with the ZONGSHEN 250cc

Water Cooled or Air Cooled?

Mudflap · 05-17-2017, 02:33 PM

Plugged crankcase vent?

ben2go · 05-17-2017, 03:55 PM

If the plug is black, there is a rich condition. If the plug is black and greasy, it's blowing oil by a valve or the rings. Did you stagger the ring gaps 45 degrees from one another when you installed the piston?

Adjuster · 05-17-2017, 04:58 PM

May just need to be ran hard to seat everything.

My first thought was also the ring gaps.

FLASHLIGHTBOY · 05-17-2017, 07:33 PM

I had one like that before... never did find out from the customer what it was,... it was an air cooled motor o a Z STAR kids quad... ran good,... if it is a plugged breather then seals leak after too much built up... do not know .. interesting

Darth Racer · 05-17-2017, 10:36 PM

I'm with Ben2go on this.

timcosby · 05-19-2017, 12:28 AM

i believe white smoke is oil and black smoke is too rich but i could have it backwards

FLASHLIGHTBOY · 05-19-2017, 12:32 AM

I do not think you will find out... white smoke is usualy moisture... cold air... but not in this aor cooled motor.... running to cool... and water is in a water cooled motor... strange one..

**JerryHawk250** · 05-19-2017, 09:10 AM

We don't know if its Water Cooled or Air Cooled? If water cooled it could be a leaking gasket letting water into the system. Also could just be oil in the exhaust that hasn't burnt off yet. I did a rebuild on my Honda 200x and it smoked when I started it but would clear up after a few minutes. Turned out to be a defective exhaust valve seal. Had no signs of oil on plug and did burn oil. It crazy how much smoke a few drops can make when in the exhaust. Drove me crazy trying to figure out why it smoked.

ben2go · 05-19-2017, 09:38 PM

Quote:

Originally Posted by timcosby

i believe white smoke is oil and black smoke is too rich but i could have it backwards

If it's white with a blue hue, it's oil and hard to see. If it's steamy white, and maybe a little gray, it's condensate. A coolant leak is usually thick and white like a cloud. It can also have a sweet smell depending on the coolant type used.

FLASHLIGHTBOY · 05-23-2017, 10:04 PM

poster just posted the help post and then left us hanging... I guess he does not need any help .. as all posting should be with all the info needed. would help do you not think????

05-17-2017, 02:05 PM	#1
mikecombs66 Join Date: May 2017 Location: Miami Posts: 1	Cinese atv Zongshen 250cc fresh rebuild white smoking at idle and acceleration, help. New fresh top end, new head,cylinder,piston,rings,head gasket, new ignition,fresh gas,fresh oil, starts and idles but white smoke puffing away at idle and reving the engine, I checked the spark plug, its black, cleaned it up and no help. Is it the new carb I put on with a bad mixture? could it be oil ? I have excellent compression. I was there when the mechanic double checked the rings and the clearance. What should I do? Its a Peace ATV with the ZONGSHEN 250cc
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05-17-2017, 07:33 PM	#6
FLASHLIGHTBOY Join Date: May 2009 Location: SASKATOON Posts: 1,161	white smoke I had one like that before... never did find out from the customer what it was,... it was an air cooled motor o a Z STAR kids quad... ran good,... if it is a plugged breather then seals leak after too much built up... do not know .. interesting __________________ DEALER FOR ZSTAR & GIO PRODUCTS, TAOTAO ABIBABA ATV ETC
	0

05-19-2017, 12:28 AM	#8
timcosby Join Date: Nov 2016 Location: robertsdale alabama usa Posts: 1,007	i believe white smoke is oil and black smoke is too rich but i could have it backwards __________________ 1991 harley heritage softail classic 2016 hawk kaw h1 400 tripple 13' long chopper in progress 2009 johnny pag bar hog 2004 hd electra glide ultra classic shriner edition 1997 harley davidson 1200 sportster 1972 harley davidson amf sx250
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05-19-2017, 12:32 AM	#9
FLASHLIGHTBOY Join Date: May 2009 Location: SASKATOON Posts: 1,161	white smoke I do not think you will find out... white smoke is usualy moisture... cold air... but not in this aor cooled motor.... running to cool... and water is in a water cooled motor... strange one.. __________________ DEALER FOR ZSTAR & GIO PRODUCTS, TAOTAO ABIBABA ATV ETC
	0

05-19-2017, 09:10 AM	#10
JerryHawk250 Moderator Join Date: Oct 2016 Location: Houma, La. Posts: 11,561	We don't know if its Water Cooled or Air Cooled? If water cooled it could be a leaking gasket letting water into the system. Also could just be oil in the exhaust that hasn't burnt off yet. I did a rebuild on my Honda 200x and it smoked when I started it but would clear up after a few minutes. Turned out to be a defective exhaust valve seal. Had no signs of oil on plug and did burn oil. It crazy how much smoke a few drops can make when in the exhaust. Drove me crazy trying to figure out why it smoked. __________________ 2023 Lifan Lycan 250 Chopper 2023 Venom Evader 2022 Lifan KPX250 2020 Kawasaki Vulcan S 2004 Honda ST 1300 2016 Black Hawk 250 (sold) Keihin PE30 carb,125 main,38 slow.Pod filter,ported & decked head 10:1 CR,Direct Ignition Coil,15/40Sprockets,NGK DPR8EIX-9,De-Cat,Dual Oil Cooler,Digital Cluster 2016 Cazador180 XL 2014 Coolster150 JerryHawk250.com My YouTube Channel Last edited by JerryHawk250; 05-19-2017 at 10:21 AM.
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05-17-2017, 02:33 PM	#3
Mudflap Join Date: Sep 2014 Posts: 1,872	Plugged crankcase vent?
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05-17-2017, 03:55 PM	#4
ben2go Join Date: Jun 2011 Posts: 1,335	If the plug is black, there is a rich condition. If the plug is black and greasy, it's blowing oil by a valve or the rings. Did you stagger the ring gaps 45 degrees from one another when you installed the piston?
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05-17-2017, 04:58 PM	#5
Adjuster Join Date: Dec 2014 Location: Deerfield Beach FL Posts: 1,410	May just need to be ran hard to seat everything. My first thought was also the ring gaps.
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05-17-2017, 10:36 PM	#7
Darth Racer Join Date: Apr 2016 Location: MD Posts: 558	I'm with Ben2go on this.
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05-23-2017, 10:04 PM	#12
FLASHLIGHTBOY Join Date: May 2009 Location: SASKATOON Posts: 1,161	poster reply poster just posted the help post and then left us hanging... I guess he does not need any help .. as all posting should be with all the info needed. would help do you not think???? __________________ DEALER FOR ZSTAR & GIO PRODUCTS, TAOTAO ABIBABA ATV ETC
	1