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800r ptek with 4mpg fuel mileage

800r poor fuel mileage carburetor

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#1 ntldbr

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Posted 17 March 2015 - 12:23 AM

I have a 2010 Gade Adrenaline with an 800r Ptek that got 4mpg on several tanks of fuel over the weekend.  Rode near Munising, MI in temperatures of 35-40 degrees F.  Issue remained across two riders, but fuel mileage would return to normal when the rpms were maintained at 6000 rpm and braking was minimized.  Recently cleaned the carbs.  Sled seemed to be overloading the fuel and would badly bog off the trail.  Is this an ECM issue due to the warm temperatures or a carb jetting issue?  Any ideas would be greatly appreciated.  Normally this sled gets 10-14 mpg depending on how its ridden.



#2 goose997

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Posted 17 March 2015 - 05:17 AM

I have a 2010 Gade Adrenaline with an 800r Ptek that got 4mpg on several tanks of fuel over the weekend.  Rode near Munising, MI in temperatures of 35-40 degrees F.  Issue remained across two riders, but fuel mileage would return to normal when the rpms were maintained at 6000 rpm and braking was minimized.  Recently cleaned the carbs.  Sled seemed to be overloading the fuel and would badly bog off the trail.  Is this an ECM issue due to the warm temperatures or a carb jetting issue?  Any ideas would be greatly appreciated.  Normally this sled gets 10-14 mpg depending on how its ridden.

Ptek engines did have a problem with DPM, I believe it was a vacuum activated solenoid or valve. There was a bulletin on the 2009's, not sure if it was sorted out for 2010. Maybe have your VIN run by dealer to see if yours is affected. I don't think jetting would suddenly cause that much of a drop in mileage. Maybe you've got a bad needle/seat causing a very rich condition?


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#3 postman24

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Posted 18 March 2015 - 12:56 PM

Rode an 08 800 for 7 years and almost 5000 miles with consistent mileage around 17 mpg and no DPM problems. You certainly have some interior carb problems. 



#4 skirider

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Posted 18 March 2015 - 01:42 PM

I would check dpm. Pull solonoid out of housing and squirt with wd40. Dont loose o rings. But i dont think that would effect fuel that bad. Maybe a leaky float. O rings on float sometimes go causing a little fuel to escape

#5 djm

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Posted 18 March 2015 - 03:51 PM

I suspect that there is something going on with the carbs since you recently cleaned them and the poor fuel economy I take it is a recent event.  

The needles and seats in the two carbs could be leaking or the o ring that surrounds the press in needle seat that supports the float could also be leaking.  Doo only services the needle and seat as an assembly.  But you can buy the o rings from Arctic Cat, they are part number ( Arctic cat dealer...6505-875) and should be less then a couple of dollars.   I want to believe you can buy them from Yamaha as I believe that is the last part number I purchased them under.  Have the package at home and can check later tonight when I get there, incase you have a Yamaha dealer close by and not a Cat dealer.  

 

Have  you richened jetting recently.. ie bigger mains or shimmed the needles to avoid burn downs?  

 

How does the sled idle, you say it loads up at part throttle, but tends to clean up around 6000 rpm?  



#6 windsurfnut

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Posted 18 March 2015 - 07:25 PM

pull your rave covers and start the sled.

Watch for the rave's to suck in.

If they do suck in, see if you can push them in any more while motor running.  You'll also notice the sound of the idle change, more crisp.

 

If the raves do not suck in, and/or they don't go in all the way then your Rave Solenoids and/or check valves ( 3 of them) are bad.

I would replace check valves anyways as they are a couple bucks each.  Solenoids are expensive.

 

If the the rave plumbing isn't working properly, the valves don't go to their proper positions.  This causes problem with correct WOT RPM, bad low and mid range power and exceptionally bad fuel mileage.


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#7 stealth bomber

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Posted 18 March 2015 - 09:35 PM

pull your rave covers and start the sled.
Watch for the rave's to suck in.
If they do suck in, see if you can push them in any more while motor running.  You'll also notice the sound of the idle change, more crisp.
 
If the raves do not suck in, and/or they don't go in all the way then your Rave Solenoids and/or check valves ( 3 of them) are bad.
I would replace check valves anyways as they are a couple bucks each.  Solenoids are expensive.
 
If the the rave plumbing isn't working properly, the valves don't go to their proper positions.  This causes problem with correct WOT RPM, bad low and mid range power and exceptionally bad fuel mileage.


This. I had a problem with the rave valves on mine this year, it caused horrid fuel mileage.

#8 djm

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Posted 18 March 2015 - 11:48 PM

This. I had a problem with the rave valves on mine this year, it caused horrid fuel mileage.

 

Sounds like you guys have this nailed. .

 

Possibly the most significant innovation for both performance and fuel economy is the new 3-D R.A.V.E. exhaust valves. The 3-D name comes from:  three-opening positions  the valves control three exhaust port openings per cylinder; and  the 3-D mapping that determines their operation. Exhaust valves are central to an engine’s performance, emissions and fuel economy – smaller exhaust ports produce the best torque, fuel economy and emissions, while larger exhaust ports produce the best power. R.A.V.E. exhaust valves, which debuted on Ski-Doo snowmobiles in the late1980’s, enabled riders to have “two engines in one” – one with small exhaust ports for idling and cruising [R.A.V.E. closed] and one with large exhaust ports for higher performance and top-end speeds [R.A.V.E. valve opened]. While the original R.A.V.E. valves were opened with exhaust pressure and timing determined by the valve’s spring pressure, today’s 2-TEC engines use crankcase pressure for the opening force and the ECM and solenoids for the timing. [The 1000 SDI operates the valves with a rotary action motor.] 3-D R.A.V.E. adds an intermediate opening position for better performance and fuel economy at the speeds most people ride [about 25-60 mph/40-100 km/h]. Engineers accomplished this by splitting the single valve/guillotine into two. When the engine is off, the primary guillotine is closed and the secondary one [including side ports] is open. At idle and at low speeds, a vacuum of crankcase pressure sucks the secondary valve closed. Then, at mid-range engine speeds, the ECM opens the secondary valve to its neutral position by releasing the vacuum. Then at higher speeds, the ECM orders crankcase pressure to push open the primary valve. Here is a simplified break-down of how the system works on a Summit: RPM Off Idle - 6200 6200-7400 7400 + Crankcase Pressure None Vacuum Neutral Positive pressure Secondary guillotine Open Closed Open Open Primary Guillotine Closed Closed Closed Open Because of low vacuum force at low rpm, the bellows have been increased in size by 42% over the 800H.O., so it has the strength to close the secondary guillotine.

 

I take it you guys are saying the valves are full open all the time?  This can be due to that valves being dirty..and is there anyway the lines or solenoids could function that would put positive pressure or hold positive pressure on the main valve and neutral pressure on the secondary valves  such that both are held open when they shouldn't be?  You need positive pressure to open the main/bigger rave and no pressure or vacuum to hold open the secondary/smaller valves.  



#9 BARK-A-LOUNGER

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Posted 19 March 2015 - 12:03 AM

Rode an 08 800 for 7 years and almost 5000 miles with consistent mileage around 17 mpg and no DPM problems. You certainly have some interior carb problems. 

 

17mpg on an 08 800.....wow! You done good........

 

I average 120miles per tank an I'm at panic stage when I'm doing that good.........usually 8-10mpg which was no better than my 2001 or 2002 800..........


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#10 stealth bomber

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Posted 19 March 2015 - 09:43 AM

I take it you guys are saying the valves are full open all the time?  This can be due to that valves being dirty..and is there anyway the lines or solenoids could function that would put positive pressure or hold positive pressure on the main valve and neutral pressure on the secondary valves  such that both are held open when they shouldn't be?  You need positive pressure to open the main/bigger rave and no pressure or vacuum to hold open the secondary/smaller valves.  

Vacuum closes both valves at idle/low speeds, neutral pressure allows spring pressure to open the secondary and side valves during midrange, top end rpm positive pressure opens all valves.

In my case the valves were in the neutral position (primary guillotine closed, secondary and sides open) at idle and low speeds.  They would not suck closed with vacuum when the engine was started.  The primary would open at high rpm so the engine had full power, the only real symptoms were terrible fuel mileagae and a slight midrange sputter.  Not real bad but just not smooth and crisp.  The eye opener for me was when I used twice as much fuel as a 800 etec in the same distance.  I chose to mod mine to open via exhaust pressure like the old valves, mainly to get back on the trails in a timely manner.  Still undecided if I'll repair the 3D system or leave it as it is now.  It works pretty darn good now.      



#11 postman24

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Posted 19 March 2015 - 01:16 PM

17mpg on an 08 800.....wow! You done good........

 

I average 120miles per tank an I'm at panic stage when I'm doing that good.........usually 8-10mpg which was no better than my 2001 or 2002 800..........

That's normal trail riding with a few moments of throttle pinning here and there. If you pin the throttle at every take off and hammer it constantly, obviously the mileage will decline. It was a good sled for mileage with real consistent mileage at just about 17 mpg flat over 7 years of riding. I am not a light rider either at 220+ lbs plus equipment. My 2015 has been anywhere from 15 to 19 mpg with alot of this season in break-in mode. I will know better next season what the real mileage factor is. Hopeing for at least 17 mpg like the 08.



#12 ntldbr

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Posted 19 March 2015 - 09:50 PM

Thank you, everyone for your advice. I'm going to tear into it this weekend, I will let you know what I find.  Thanks again!!



#13 sleeperzx

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Posted 21 March 2015 - 07:27 PM

don't over look the needle and seat. these are prone to leaking on older sleds and make a huge difference.


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#14 Tollefry1

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Posted 13 February 2019 - 05:08 PM

I went riding last weekend and had similar problems. I have an 09 800 ptek. the thing absolutely ripped at full throttle. It has a MBRP can on it which gave me a clue something was wrong. At full throttle it would rip, then when I let off it would bogg down and was very loud. It seamed like it may be flooding? It died a couple times on the trail, we could smell gas and after 50 pulls would fire and smoke quite a bit. It went through an entire tank of fuel in roughly 50 miles. It was also -20f which could have played a part, but I'm not sure. At first I was thinking a carb issue, but the loud exhaust bog when backing off the throttle makes me think "open raves". the next day I rode it and tried feathering the throttle down after a long pull and it seemed to help/exhaust was quieter. I would do a pull, then back to half throttle, it would be loud as heck on the trail, i would feather it and it would quiet down. I didn't see a response from the original poster; did it ever resolve, what did you do to diagnose?  Thanks guys.



#15 stealth bomber

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Posted 13 February 2019 - 05:22 PM

Remove rave valve cover.  Start engine and see if valve closes. 







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