Polaris ATV Forum banner

1 - 4 of 4 Posts

·
Registered
Joined
·
2 Posts
Discussion Starter #1
Hello all! My name is Rob. I am new to the ATV world. I have been working on cars my whole life, but never messed with ATVs much. So here is my story.

I recently picked up a 2009 Sportsman 850xp EPS for what I thought was a good price $3,500. I am slowly starting to regret it. It ran ok when we looked at it. It was a little rough, but the owner said that it sat for a while and the gas probably turned. Fair enough.

Once I got it home the problems began. I had a check engine light and the machine would fall on its face and stall. Pulled the air filter out and cleaned out the air box. It had a nice big mouse nest in it. Checked the engine code and it came back for throttle cable being out of whack.

I put a new air filter in it, cleaned out the airbox, adjusted the throttle cable, and put new plugs in it. Fired it up and it runs a million times better. No CEL and it idles smooth now. I had the side plastics off when I was doing the plugs and I didn't put them back on right away.

So last night I take it for a ride to get it up to temp. I warmed it up slow and then got on it a bit. I noticed out of the corner of my eye a red glow. The head pipe on the front cylinder was burning red hot. When I let off the throttle I noticed a small flame around the pipe. It went out rather quickly but sort of startled me. I expect the pipes to get hot but not hot enough to catch the matting around the pipe of fire!

The machine has plenty of power. It pulls the front end with my large backside (325lbs) on it and is a beast. I would assume that that cylinder is running lean to be that hot.

How do I verify / find the source of the lean condition? With a car or truck I could look at live engine data and see what the fuel trim shows/o2 sensor voltage and figure out if it is actually lean or not and how bad. With this I am at a lose. I am new to these machines and don't understand how they adjust fuel trim.

Any thoughts?

Trying to get the machine ready for hunting season up here in northern NY.
 

·
Registered
Joined
·
7,461 Posts
It's fuel injected - just plug it into the computer and see what's doing

To the best of my knowledge there is no 'matting' around the head pipe, but my CRF runs red hot for about 10 inches from the head and once I tried running 100 octane (calls for min 93) and the exhaust ran exceedingly hot - melted the side cover over the muffler on the rear of the bike (about 4 feet from the head) - a red head pipe is mostly normal - the exhaust temp is about 1200 degrees - it didn't do it at idle and it didn't do it with the cast iron exhaust manifolds, but my 65 Mustang with steel tube headers glowed a dull red when running 70 MPH down the interstate. First time I noticed it I had just pulled into a rest stop on I-65 in Indiana and parked under a tree, got out of the car and saw a glow from under the car - thought it was a fire under the hood - grabbed a fire extinguisher, opened the hood and saw the headers glowing - ran the car over 100,000 miles and never hurt a thing. I noticed the head pipes glowing on my 72 Triumph 650 Bonneville glowing the first time I was running it in the garage - wasn't sure what I was seeing, so I turned the light off and that confirmed what I was seeing. I don't worry about it unless I can see the glow in sunlight. My CRF will make the pipe glow in sunlight after about 20 minutes of hard high speed riding and it's been that way since 2004.
 

·
Registered
Joined
·
2 Posts
Discussion Starter #3
It's fuel injected - just plug it into the computer and see what's doing
This may sound stupid, but is there a way to plug into it? I mean multiple scan tools for auto use, but I didn't think I could do that with this machine.
 

·
Registered
Joined
·
7,461 Posts
All you need is the interlink for the data port and a program called Digital Wrench for a laptop computer (proprietary for Polaris dealers) or a scan tool and the program for Polaris ATV's like TEXA or ANSED offers.

Ask your scan tool manufacturer if they have software and link for Polaris - ANSED is $2999 for the tool, $169 for the cable and software update if needed is $649 to $999.

Your friendly Polaris dealer will plug it in and run the diagnostics for $300 or less - my local Polaris dealer has a flat $150 minimum for diagnostic scan with no related service work.
 
1 - 4 of 4 Posts
Top