Yamaha Grizzly ATV Forum banner
1 - 20 of 63 Posts

·
Registered
Joined
·
52 Posts
Discussion Starter · #1 ·
My machine is a 2010 700 with about 500 miles on it.

I seem to be experiencing what everyone describes as "boiling gas". Supposedly it's only supposed to occur in older models, but my symptoms are the same when it happens: high elevation (10,000 or so), half a tank of gas or less, hot day, long tough climbs, and it acts like it's running out of fuel. If this were a carbed quad, I'd say it was vapor lock.

I can restart it by waiting for it to cool, but that's it. It will then run fine if I head downhill or do something to ease the load on the engine. Otherwise, it will die a short time later.

I tried opening the fuel cap, and no pressure seemed to be present. However, I can hear changes in the fuel pump sound, like it will not be sucking fuel, and then all of a sudden start sucking. Perhaps there is boiled gas in the fuel line?

Thoughts? It's frustrating to have to sit and wait with my big, bad 700 while my wife's old carderated Bruin 350 never misses a tick.
 

·
Registered
Joined
·
2,993 Posts
Wrap the fuel line with some heat tape and try that.
 

·
Registered
Joined
·
52 Posts
Discussion Starter · #4 ·
Thought about the heat tape; seems like it would be worth a shot. Some stick-on heat shielding on the bottom of the tank might not hurt either.

I don't have any pressure build up in the tank, so would eliminating the roll over valve really do anything?

I talked to my dealer about it as well, since it's still under warranty. Unfortunately, they weren't much help. I'm reluctant to even take it to them, as I'm sure their diagnosis will be "we can't replicate your complaint".

Other ideas?
 

·
Registered
Joined
·
1 Posts
I have a 2011 700 with less than 500 miles on it and have experienced the same “WTH – I just ran out of gas” problems as you.

In my case it has happened three times, all while riding the Alpine Loop in Colorado. Twice while climbing at around 10,000 feet and once while descending.


The first time I thought it has gotten hot and vapor locked, but I didn’t think it was that hot as the coolant temperature light had not come on. In all cases it would not start immediately and acted like it was not getting any gas but would start after several minutes. Speed was about 20 – 25 and grade was not that steep and the temperature was in the low fifties.

The only thing that was different this time was that I was using “local” gas which was 85 octane with ethanol where I had been using 87 octane with no ethanol.

I have checked the roll over valve, as that seems to be a problem with the older 700s, and it is functioning like it should.

I am also looking for an answer.
 

·
Registered
Joined
·
6,418 Posts
The rollover valve when it malfunctions simply is closing when it should be open and venting fumes and relieving pressure. If you have no pressure buildup in the tank there is nothing wrong with the valve and it's not the cause of your altitude problems. At higher altitudes, air pressure is lower. The reduced air pressure lowers the temperature at which gas boils. So, gas actually boils faster at higher altitudes. The more additives in the gas the lower the temp it boils. Ethanol and gas boils at a lower temp than straight gas- it's crap- don't use it at any altitude in a Grizz. A fuel pump making it's normal sound when the gas is not boiling will make a different sound when it's pumping a liquid full of bubbles. So you guys having problems at 10,000 feet must use 87 octane with no ethanol. If that's not enough the only other option would be to lower the temp in the gas tank by wrapping it with heat tape.
 

·
Registered
Joined
·
327 Posts
Wrap your exhaust, or get a heat reducing coating.
 

·
Registered
Joined
·
52 Posts
Discussion Starter · #9 · (Edited)
TXHornToad: sounds like exactly the same issue. Hopefully we can figure it out!

Thanks guys. I fell better messing with the heat wrap, etc, with some confirmation that i might be on the right track.

Unfortunately here in CO, etha-gas is what we have. I might search for some other additive or something that might help though.
 

·
Registered
Joined
·
52 Posts
Discussion Starter · #11 ·
There are a few places in colorado that sell pure gas. Here's a list:

Ethanol-free gas stations in CO

That's interesting, thanks! I thought they were all the same here. Naturally none of the stations listed are near me, but it does suggest that I should keep my eyes open locally for variations in ethanol content. Even if I could find a station that's lower it would help.
 

·
Registered
Joined
·
139 Posts
So funny guys. I just got back from the alpine loop and my grizzly did the same thing. 2010 with 250 miles on it. it died three times coming back up stony pass. Ran great on the way over with a full tank. But coming back with less than half it wouldnt make it. This really pissed me off. My dad just sat and waited on his popo two up running. I went to the dealer in montrose the next day. They checked the roll over valve and it was ok. Then they called the yamaha tech line. The tech line wanted to put a new spark plug in and a new fuel pump in. but they didn't have one in stock . so I ran it the next day with a full tank for forty miles with no issues. its scheduled to go to my dealer here in Denver on Tuesday so we will see what they do. to me this shouldn't be an issue to begin with and I'm pretty disappointed. I bought this ride and fell in love with it because it seemed to be the most well built and reliable machine. But to see my dads popo never miss a beat while I can't even make it up a mildly graded pass was very disheartening. I'm not happy. all we ride out here in Colorado is high altitude. I can't be worrying that this thing is going to crap out at high altitude when I'm actually in the rough stuff. Maybe I'm being over sensitive but to me I shouldn't have to wrap my gas tank or fuel line to ride at high altitude. this is something Yamaha should have found in R&D. We will see what the dealer comes up with. A few more notes. I was climbing a five to six percent grade between twenty and twenty five mph. I was running 91 octane fuel I had about 3/8 of a tank and it was about 55° outside.
 

·
Registered
Joined
·
6,418 Posts
Maybe I'm being over sensitive but to me I shouldn't have to wrap my gas tank or fuel line to ride at high altitude. this is something Yamaha should have found in R&D. We will see what the dealer comes up with. A few more notes. I was climbing a five to six percent grade between twenty and twenty five mph. I was running 91 octane fuel I had about 3/8 of a tank and it was about 55° outside.
It 700 Grizz wasn't designed for 91 octane. 87 octane ONLY. The octane boosters make it boil at lower temps. The high altitude makes it boil at lower temps. Corn gas boils at lower temps also.
 

·
Registered
Joined
·
139 Posts
It 700 Grizz wasn't designed for 91 octane. 87 octane ONLY. The octane boosters make it boil at lower temps. The high altitude makes it boil at lower temps. Corn gas boils at lower temps also.
Thanks way up. For some reason when I bought mine during the walk around the tech told me that's what they recommend. I have no idea why. do you think this was my whole problem? Wrong octane? seems like its got to be something else also?
 

·
Registered
Joined
·
6,418 Posts
Thanks way up. For some reason when I bought mine during the walk around the tech told me that's what they recommend. I have no idea why. do you think this was my whole problem? Wrong octane? seems like its got to be something else also?
Your engine has to be built up, High Compression piston etc to run higher than 87 octane. There is a confusing sticker on the grizz is how people think it says 91 octane. All the yamaha utility atvs are designed for 87 octane. This contributed to your problem of boiling gas. IMO the fuel pump starts sucking bubbling liquid instead of pure liquid and fails to give it enough gas to keep running. Are you sure the tank is venting properly when this happens? Like no pressure in the tank when you loosen the cap? I doubt yamaha tests these machines at 10,000 feet. I know they don't test them for riding on glaciers, crossing real deep water or for riding at 50 below zero either:icon_ goofy:
Try again with the right gas for sure. Don't give any techs any of your money. Telling you to run 91 octane and telling you they want to replace the fuel pump makes them sound kinda stupid to me.
 

·
Registered
Joined
·
139 Posts
Well its all under warranty so I'm definitely not paying a cent. I will see what they say when they look at it and keep you posted. Completely unrelated question. Manuel says we have a 5.28 gallon tank and a 1.19 gallon reserve. When my gauge goes to empty and the light comes on does this mean I've started into the reserve or have I already used the reserve up? Also what is your average range? I did 70 miles at high altitudes averaging between 10 to 25 mph and using the throttle fairly heavy to feel that griz power lol. At 70 miles my low fuel light came on. sound about right?
 

·
Moab Aficionado
Joined
·
2,382 Posts
A few things that I have done to run high altitude is put in a K&N filter and a aftermarket exhaust tip. This leaned up the Grizzly and eliminated my high altitude problems. I also run 85 octane fuel. Higher altitudes need lower octane fuels.

When your fuel gauge starts to blink, you are into the reserve portion of your fuel.


---
I am here: http://maps.google.com/maps?ll=41.132487,-111.928178
Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
52 Posts
Discussion Starter · #18 ·
I did 70 miles at high altitudes averaging between 10 to 25 mph and using the throttle fairly heavy to feel that griz power lol. At 70 miles my low fuel light came on. sound about right?
Sounds pretty good to me. With lots of 4x4 use and a heavy load, I've approached as low as 10 mpg.

Please keep us updated on your experience with the dealer. It's somewhat comforting to know I'm not the only one with this frustrating problem, now we just need to find a fix!
 
  • Like
Reactions: CO303rider

·
Registered
Joined
·
467 Posts
I seriously think you should try one tank of Regular Unleaded instead of Premium Unleaded and see if it behaves any better. I know it sounds like nonsense but it can make a difference sometimes. It was proven to me.

I live at 7,200' and most all my riding is at that elevation or higher and other than getting strong fuel vapors on hot stops I haven't had any stalling issues.

I would also change the spark plug. They look fine when you pull them out but they can cause problems. I changed my after the first 50 miles and mine ran so much better and doesn't stall on cold startups anymore.

DEWFPO
 

·
Registered
Joined
·
6,418 Posts
A few things that I have done to run high altitude is put in a K&N filter and a aftermarket exhaust tip. This leaned up the Grizzly and eliminated my high altitude problems. I also run 85 octane fuel. Higher altitudes need lower octane fuels.

When your fuel gauge starts to blink, you are into the reserve portion of your fuel.


---
I am here: Google Maps
Sent from my iPhone using Tapatalk
Good points! Another thing I would try is what EPI calls a "altitude" clutch kit. I don't mean buy their kit I mean use their method for altitude:icon_ goofy: Install either 4 or all 8 lighter weights. Use 18gr, your stockers are 20. Seeing how you ride 10-25mph when this problem occurs the lighter weights will hold you in a low ratio longer or in the powerband better at altitude and your speeds. X2 on the sparkplug!
 
1 - 20 of 63 Posts
Top