Oil and fuel coming out of exhaust

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Tonemaster
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Joined: Tue Aug 11, 2015 4:31 pm

Oil and fuel coming out of exhaust

#1 Post by Tonemaster » Sat Aug 29, 2015 4:45 pm

Hey all. New to the forum, and new to 2 strokes. I know my way around 4 strokes no worries, but these smokers!! I recently acquired an 86 RZ 350, and got the carbs all cleaned, nre needles and seats, and went to fire her up. She started right up, but the exhaust was leaking on right side badly, so I shut it down immediately. Quite a lot of oil and fuel leaked out of the exhaust port. Is this normal, or is there something amiss I don't know about? I will not re-start until I get some feedback.

T.

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RZResurection
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Joined: Sat Jul 15, 2006 9:51 pm

Re: Oil and fuel coming out of exhaust

#2 Post by RZResurection » Sat Aug 29, 2015 5:54 pm

Might have fired up, but sounds like it was only running on one cyl. with all that un-burnt fuel coming out. Check compression and spark.
Jeff

Trying to build a bike that's as fast as my memories
87 Canadian 1WV
OEM Pipes
Gutted Airbox
VF4 Reeds
Milled Head (0.020")
Main 240
Pilot 27.5
02 R1 Front End
R6 Shock and Rims (180 Rear Tire)
84 FJ1100 Swingarm

Tonemaster
Posts: 2
Joined: Tue Aug 11, 2015 4:31 pm

Re: Oil and fuel coming out of exhaust

#3 Post by Tonemaster » Sat Aug 29, 2015 7:18 pm

Lots of spark, also new plugs. I will check comp.

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vonzipper
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Location: Calgary Alberta

Re: Oil and fuel coming out of exhaust

#4 Post by vonzipper » Mon Aug 31, 2015 1:38 pm

The bike was probably flooded sometime ago and gas oil mixture have accumulated in the exhaust pipes, you need to remove them and drain out the unburnt mixture in them also flush out the pipes. In addition check your float levels and needle check valves in the carbs for leakage or flooding.
90 RZ350 Track bike.
86 RZ350 Stock daily runner.
84 DT200
84 RZ500

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pushstartrearset
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Re: Oil and fuel coming out of exhaust

#5 Post by pushstartrearset » Mon Aug 31, 2015 3:05 pm

Might be a good idea to re-pack your perforated cores also. They'll be soaked w/ that mixture. Since you have already replaced the needle valve seats, I would agree w/ Vonzipper. Also find out if you have a leaky petcock. I rebuilt ours, kind of tricky, but it is working....the membrane replacement is very thin, but the easiest solution is a N.O.S. petcock if you want to avoid that.
1984 RZ350L (U.S.) Old Toomeys, oil injected!, Y-boot K&N. loctite throttle cable holder on left carb!! , 410 mains, Dynojet needles 2.0 clip, #20 pilot @ 1.5 turn a.s., 240/512 p.v.

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