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Sportsman 800 Twin / gas in the oil

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Old 04-19-2017, 06:49 PM
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Default Sportsman 800 Twin / gas in the oil

Hi all, new to forum. I have an issue with my Sportsman 800 getting fuel into the oil. I'm sure it's fuel and not coolant. I found the oil level about 3/4" higher than normal and it smelled heavily of gas when I drained it. Ran it with fresh oil and it happened again over the course of several rides. I figured it might be a sticking injector so I replaced both with new ones and it did it again. I just replaced the ignition coil and plugs/wires and changed the oil/filter yet again. Throughout the entire issue the bike has ran great and idled smoothly. Compression is 168# on one cylinder and 148# on the other. Any suggestions or advice is appreciated. Right now I am using the quad lightly and keeping a close eye on my oil level.
 
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Old 04-20-2017, 01:47 PM
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This is something for Digital Wrench. They can reflash the ecm to help solve this excess fuel problem or it can find the reason why it is doing this.I wouldn't throw any more parts at it.
 
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Old 04-20-2017, 03:21 PM
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Thanks. I'll get it down to the dealer soon. I'm afraid I have a ring sticking. What are your thoughts on the compression numbers?
 
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Old 04-20-2017, 05:05 PM
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Manual says between 150 and 200 psi. Getting kinda at minimum on one cylinder but considering the other one,there's just a little over 10% difference between the two. If it's been running good other than gas consumption it may not be anything to worry about yet. Just let Digital Wrench do it's thing and go from there.
 
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Old 04-20-2017, 05:54 PM
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Will do. I appreciate the advice.
 
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Old 04-25-2017, 08:00 AM
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Well, I was concerned at the low compression on the one cylinder and the spread on the compression numbers between cylinders was pretty large. I found an old post from a guy that claims to have "un-stuck" hundreds of rings over the years using Marvel Mystery Oil. I figured why not give it a try so here is what I did and the results of the experiment so far:

*changed the oil again and added 20% MMO to the crankcase and ran the quad a couple of days.

*added 2 oz of MMO on top of each piston while the engine was warm (not hot). I let this soak for ~24 hours, removed any excess from the top of the piston and ran the machine. It smoked HEAVILY for a couple of minutes and then cleared up.

Before and After compression numbers:
Cyl 1: 148# to 160# Cyl 2: 168# to 172#

Soak #2: Added another 2 oz of MMO on each piston and let it soak ~24 hrs. Ran the bike - it smoked a little and cleared up quickly.

Before and After compression numbers:
Cyl 1: 160# to 182# Cyl 2: 172# to 181#

Looks promising but I'm not calling it a done deal quite yet, but I am happy about the compression gains. I'm watching my oil level closely and hoping my problem with getting fuel in the oil is fixed. I'm still planning to take the bike to the shop to have the ECM re-flashed as well. This is the first time I've ever used this snake oil but so far I'm pleased with the results. Right now she's got fresh oil/filter and new plugs so we'll see how it goes.
 
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Old 04-25-2017, 11:28 AM
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If it helps like it seems to be doing then that may help on the fuel in the oil. I've seen this stuff for years,but never tried it especially when I read it was responsible for air craft engine failures years ago.That may have been the mechanics fault on mixture ratio,etc.
 
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Old 04-25-2017, 11:41 AM
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At least if it causes my engine to fail I wont be at 30,000 ft.

At this point I've got fresh gas and oil so most of the stuff is out of the engine. I'm still planning on letting the dealership check it out with the Electric Wrench just for good measure.
 
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Old 04-25-2017, 11:59 AM
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What I heard was that they used too much in the fuel and it leaned out the octane causing seizures in old prop planes. A lot of posts I've read is that it's good for engine flushes also as it's close to naphtha.
 



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