Any snowmobile mechanics? Polaris 600 twin

[pmer]

Just took home a 2013 Polaris iqr 600, I had out this morning and after it warmed up it died at 3/4 throttle after about 1/4 mile. So I waited a bit and it started went about 300 yards and died. It did this 2 more times and by then it got parked in the yard.

Can a fuel pump act like that or maybe it was too hot and shutting down? It has plenty of gas and the coolant level looks good.

[Winger Ed.]

Fuel pump would be a good place to start looking, if you're sure the fuel filter is clean, and the fuel itself is good.

[Three44s]

After it dies, does it still have spark?

Ignition coils and modules can work sporadically. The component heats up, the circuit opens due to a break and you lose fire. The component cools off and the process repeats itself.

Fuel and oil supply are also issues. I have seen 2 stroke oil that was old enough that it congealed. You can get restarted from some seizures especially after the engine cools down. The fuel/air mix is another matter. A snowmobile that is adjusted for high altitude can size due to too lean of a fuel adjustment. You could also have something foreign in your carburetor.

Best of luck

Three44s

[Tripplebeards]

You could have a air leak somewhere to. I had the same issue years ago and it had a warped head. It would suck Cold air After it heated up and the head flexed. Get a vacuum pressure and compress kit at harbor freight if there’s kit and try it out. You might have a ripped or torn gasket not sealing properly as well. Look for all the fuel filter locations, there could be one I the line somewhere and replace them. It’s a cheap try. I hate snowmobiles! Every time I drove them they broke her head issues I’d rather walk. I had one with a leak like that they kept popping pistons. It get warmed up suck cold air through somewhere and that all that’s all she wrote two times in a row. That was back in the early 90’s. I haven’t looked at one or bought one cents and that’s the happiest day I ever had was selling that sled. If all those things check out it could be electronica as well like a brain box heating up causing a circuit to open and shut off. Start with all the simple stuff first I’ll keep my fingers crossed for it.

Good call 3,44’s!

Like 344 said above ignition coils will do that when they heat up!!!! I forgot all about those! My outboard motors would do the exact same thing. If you have a dealership around pull the ignition coil‘s and get them tested. I’m guessing 344’s is right on the money!

[Misery-Whip]

Sounds like a fuel issue. Is the fuel shuttoff valve working correctly, change the fuel filter, is the fuel tank venting properly, is the fuel line rotten or swelled? Try switching over to reserve there may be a restricted passage in that valving.

Next time it dies test for spark, then take the fuel line off the carb or fuel rail and gas should be pouring out the hose([B]now please be careful with this tip mind hot exhaust and electrical)[B]

My experience with fuel pumps is when they quit, thats it....Now a relay in the fuel pump wiring, ive seen relays that turn off when hot. Any other systems not work when it dies?

[Three44s]

+10 Tripplebeards!

Snowmobiles are better used in numbers! More people to dig you out after you get stuck! More chances you can ride double back home or get towed in!

They are expensive to feed non acohol gas to as well.

But when things work, they are lots of fun!

Three44s

[pmer]

+10 Tripplebeards!

Snowmobiles are better used in numbers! More people to dig you out after you get stuck! More chances you can ride double back home or get towed in!

They are expensive to feed non acohol gas to as well.

But when things work, they are lots of fun!

Three44s
So true and completely agree!

[pmer]

Sounds like a fuel issue. Is the fuel shuttoff valve working correctly, change the fuel filter, is the fuel tank venting properly, is the fuel line rotten or swelled? Try switching over to reserve there may be a restricted passage in that valving.

Next time it dies test for spark, then take the fuel line off the carb or fuel rail and gas should be pouring out the hose([B]now please be careful with this tip mind hot exhaust and electrical)[B]

My experience with fuel pumps is when they quit, thats it....Now a relay in the fuel pump wiring, ive seen relays that turn off when hot. Any other systems not work when it dies?

It's carbed not injected. Thanks for tips on checking for spark. It does have a fuel shut off and I cracked open the fuel tank each time it died. I don't think it has a reserve. Fuel pump looks original.

Any other symptoms- not that I now of, it's pretty plain Jane, lights light up when I crank it. Couldn't tell if the handle bar warmers got warm.253075

[Tripplebeards]

You have two people telling you to check the coils. If I were you I’d be checking those before I do anything else. Call a shop and get their opinion as well. Good luck! It’s probably an issue inside the coil(if that’s what it is) but you can always do a quick visual to see if they’re cracked. I’ve seen it in a lot of cars as well I just always forget about the coils. I have an 04’ F150 that had two coils out of eight going out when it got hot and started missing horribly. Cold it ran like a top. I had a couple of cars in years past it did the same thing with a single coil, it would just kill after it got hot and it would start right back up when it cooled off.

Last sled I had I used on the river more than anything. I had carbide runners and I think 102 cat claws on the track. I remember seeing my first Red Fox in the neighborhood. I jumped it and ran across the river. I got right up next to him and passed him like he was standing still. Boy, that thing would throw sparks going across the road.

[pmer]

I kinda wish it was fuel because it seems easier to spot a issue with fuel delivery but this one seems more like it's getting shut off than sputtering out like the typical fuel issue.

It should be a load of fun when it gets fixed. It has the deep lug track with the carbide picks too. These IQR's get bounced around pretty hard.

[LaPoint]

Does it only die under partial or full throttle? Will it idle indefinitely? If it will idle for an extended period of time it is most likely a fuel issue. Either an air leak or more likely a problem with fuel pressure. You can try putting it up on a stand and very lightly pressurizing the tank while accelerating to see if it is a fuel pressure problem. Just make sure it doesn't fall off the stand when you have the throttle opened up!

[BamaNapper]

Not much snow here in AL, but I've fought my share of 2-stroke outboards. A quick look at partzilla says your engine has one coil and CDI. Yes, the CDI can get temp sensitive and would kill it all at once. Like mentioned, check for spark as soon as it quits, before it cools off. Ouch, that CDI module is costly.

Then remember the adage of 2-strokes: "If it's not running right, it's a fuel problem 90% of the time. Correction; it's a fuel problem 99% of the time."

Partzilla again, your fuel system has a single pickup in the tank, an impulse pump (not electric), and 2 normal bowled carbs. Gotta love simplicity. If it was my machine the first step would be to change every bit of fuel and vacuum line, including the line inside the fuel tank. It's cheap, quick, and would assure me that there are no leaks and the in-tank pickup is clean. If you want, you can even install small clear fuel filters on each side of the fuel pump to get a visible of whether fuel is getting to and through the pump. As a test, a tee fitting in the output of the fuel pump with a piece of clamped off fuel line will let you see just how much flow you can get through the pump when it’s running. Almost certainly not a carb problem since a failure of both at the same time just doesn’t happen, and it should continue to run on one.

The impulse air line from the carb is just as important as the fuel line since it's what operates the pump. Failure to get impulse air is the same as pump failure. An air leak can seriously limit or stop fuel flow, especially at higher RPM. BTW, that impulse comes from the intake so there are gaskets that come into play. I've seen a carb gasket on a chainsaw engine installed backwards from the factory, blocking the impulse. The choke would move enough fuel to get it running for a while, but it gave me fits.

When it comes to this type of fuel pump, some can be rebuilt. They're just a couple check valves, spring & ball type, and a diaphragm, not much to fail. If you disconnect the fuel line to the carbs, then extend the impulse air line to the pump you can blow into it. You shouldn't be able to blow air through it as you're blowing against the diaphragm. But if the diaphragm is torn you'll blow right past it toward the carb. Fuel pumps can die from check valve failures but diaphragms seem to be the usual culprit. Amazon also carries impulse fuel pumps, some under $10, if you can find one to fit your fuel/air line size with adequate flow that would work in a pinch. I do wish you luck sir. And you're right, it's going to be a blast once it's running well.

[Three44s]

It's carbed not injected. Thanks for tips on checking for spark. It does have a fuel shut off and I cracked open the fuel tank each time it died. I don't think it has a reserve. Fuel pump looks original.

Any other symptoms- not that I now of, it's pretty plain Jane, lights light up when I crank it. Couldn't tell if the handle bar warmers got warm.253075

Don’t think that the lights or bar warmers indicate ignition spark because they are separate circuits.

Best regards

Three44s

[pmer]

Thanks for all the advice everyone. I have to check out Partzilla. I had it out again and it was a repeat of this morning. After a minute or so warm up it went about a mile and died. I pulled the cord right away and almost started and then died so it must've had some spark. Then using choke and pull starting it would start and go a little ways and die again. So I'm going to have to dig into the fuel system.

The seller said he did the lines and filter inside the gas tank and some other new items like slides, 2 drive belts (1 spare) and freshened up the motor. But its always a gamble buying used. I suppose it better for me that its acting up now instead of out on a trail next month. At least I'm getting a clue now with it at home LOL.

[Three44s]

Make certain that the pull rope is really long, very long and that there are good trees close where you ride!

That way if it don’t start and you are in the notion ..... you can hang yourself!

That was the advice with the old Cat D4’s and D6’s with the old cantankerous 2 cylinder opposed gas starting motors when they would not start, rope lots of rope!

Does this sled die “one cylinder at a time” or both? I ask this because you have two of some things and one of others. Does it miss on one side at the very first or just cut off totally abruptly?

The previous owner remembers what he/she remembers about changing this or that but may or may not want to remember every detail.

The fact that you choked the engine and got a bit more sputter out of it right after it died tends to send me to fuel. I would still view spark with a yawndous eye for now do not rule it out as the “quality” of your spark can be an issue as in yellow vs. blue. You want blue, the kind that will knock over a bull! I trust you have changed spark plugs as well?

So turning to fuel then.

You (assume) have two carbs? On the other hand just one delivery system? The pick up in the tank and the hoses, the fuel pump and vacuum system that powers the pump.

Hoses depending on construction can collapse under vacuum. Crap can move into then away from a blockage position. Even with the best of intentions we can think we did a complete job but maybe there was one little stinker the previous owner just did not have? A problem that allows air into the system is also possible.

That previous owner did not dive into the sled for laughs and giggles you know, something lead that person to fool with it (most likely).

Though I figure you have two carbs, I am a firm believer in boiling them out and kitting them just for good measure.

I mentioned this before but was this sled ran at high elevation? Sleds ran at high elevation are set for thinner air (less fuel). When we run them at low elevation they are running too lean. Over time they burn down. I just want to make sure you are not in that scenario.

For laughs and giggles I would reset the fuel metering needle clips one notch lower on each side which actually RAISES the pins one notch to see if you fattening the fuel just a bit gives you too much fuel or a happier sled. You read the plugs and listen to the motor as well.

When I am satisfied that the fuel is fixed but still a little uncertain about the Oiler and engine temperature I will throw in a measured amount of Marvel Mystery Oil right in the gas tank. The people riding behind you will not appreciate it but thems the brakes. I can not emphasis keeping the engine cool enough, fuel setting and lubrication and in particular when operating at low elevations when we are talking two strokes.

While we are talking about heat, are you on a hard pack road or are you getting plenty of “friz” by running on loose snow? You want plenty of friz getting up under your tunnel.

Hang in there, what does not kill us makes us stronger!

Three44s

[Three44s]

By the way we warm up our liquid cooled sleds until you read some water temp on your gauge. One minute is not enough.

I do not time it but I am thinking five minutes? Do not know actual time because we make certain by going by readable coolant temperature.

Three44s

[Tripplebeards]

I remember with my 4wheeler and some of my my Sea-Doos the fuel petcocks were clogged. You can test yours by turn it from reserve to on (back-and-forth) and run it to see if it still kills in both settings. I don’t know if you have a fuel petcock on your sled being fuel injected.

Another way to check for an air leak (which it probably isn’t) is spraying a light mist of carb cleaner around the motor while it’s running to see if it sucks in and causes it to killer or run faster.

I didn’t remember the part ....but it was the CDI box the above poster mention went out on my outboard motor causing the same issue as well. When it gets far into the electronics it’s above me and I have no tools to figure it out or test it. That’s where YouTube becomes my friend.


Aren’t snowmobiles fun!:groner:[smilie=b:

[john.k]

Hey,snowmobiles got to be less trouble than jet ski s.......neighbours got drowned by his kids....so he let it set for a month.....couldnt get the engine apart ,so levered the cylinders up with a crowbar,and cut the conrods with a hacksaw......I reckon he s a dealership mechanic.

[pmer]

I remember with my 4wheeler and some of my my Sea-Doos the fuel petcocks were clogged. You can test yours by turn it from reserve to on (back-and-forth) and run it to see if it still kills in both settings. I don’t know if you have a fuel petcock on your sled being fuel injected.

Another way to check for an air leak (which it probably isn’t) is spraying a light mist of carb cleaner around the motor while it’s running to see if it sucks in and causes it to killer or run faster.

I didn’t remember the part ....but it was the CDI box the above poster mention went out on my outboard motor causing the same issue as well. When it gets far into the electronics it’s above me and I have no tools to figure it out or test it. That’s where YouTube becomes my friend.


Aren’t snowmobiles fun!:groner:[smilie=b:

No this one has 2 carburetors. It's jetted for 10 - 40 degress and has been ran in Michigan and Minnesota. It has a petcock as well.

Hoping I can get it in the shed after work and get a closer look at the impulse and fuel lines.

The sellers warm up sequence was pretty short and his drive style was constantly on and off the throttle.

Its premix only - no oil injection. 32 to 1 I'm supposed to buy Amsoil Dominator.

[Three44s]

It is not temperature as much as it is altitude as far as the the fuel air mixture goes.

It sounds like your sled stayed or came from your locale and I am assuming you do not have much altitude variations like we in the west encounter. Here in the Cascade Mts. I can be at 1000 to 2000 feet, leave that and be at 7000 in an hour riding. In the Rockies that would be “child’s play” except that the base altitude would be more like 4000 to 6000’ with the higher elevations being even higher.

From your description of the previous owner they did not treat your newly acquired sled very well by not warming it up properly. That along with the sled being a gas/oil mix .... you could really be in for it.

Best regards

Three44s

[6bg6ga]

One question seems to come to mind here...as altitude increases doesn't the mixture get richer with a carb? Maybe I'm remembering incorrectly but I thought I remembered my father having to lean change to smaller carb jets as altitude increased in the car many years ago.
Of course you don't have that problem with a fuel injected engine with a ECM.

So far some good information...Check spark and the quality of the spark/color and intensity.
Allow the sled to warm up some
Quality of the gas/oil mixture.. if old then dump and renew.
Follow a precise plan and record results and do one thing at a time.

[robg]

if its a carb model check fuel tank breather aint blocked.

[Jniedbalski]

Most of two stroke problems are usually coil getting old cutting out when hot or fuel problems caused by vacuum leaks. Gaskets ,fuel line sucking air, pin holes air leaks . The two stroke works on vacuum. If you have a leak it acts as a carb problem usually . Getting hot and just shutting down sounds like a coil. If it’s a 32 to one mix I always run my two strokes at 20/1 so do a lot of go cart racers No matter what year or mix

[pmer]

I got to a dealer today and they sent me away with a rebuild kit for the fuel pump. It also needs a grommet style seal for the fuel tank. And got the correct spark plugs at the same time. I didn't see any hoses that were obviously bad. But I can keep digging.

Facebook has a group on these snowmobiles too. I have to wait a couple days for the fuel tank seal.

[Tripplebeards]

I can tell you another way to test those coils before you tear that fuel pump apart and start a project that you might(probably)not need to. Take a heat gun and apply heat the coils while it’s running and see if it kills. If the engine stops running there’s your answer. It will save you a lot of time tearing apart that fuel pump. You can pick up a heat gun from harbor freight for around $8. A blow drier might work but probably won’t get hot enough.

There’s basically no way to test a fuel pump for all you can do is rebuild it and test it and find out if it still kills. This is about the only way I know how a test a coil before you have to start spending any money.


In all the time I’ve seen fuel pumps go bad 99.9% it’s not like the conditions that you are experiencing. When you turn on the ignition you can hear your electronic fuel pump make a humming noise...because it working. If it doesn’t run it’s defective. I’ve had them get clogged and they run like the vehicle is missing and three cylinders. It isn’t impossible to say that’s not what’s going on with your sled but Id STILL tell you to test your coils with a heat gun first, it’ll save a lot of time and energy and at least rule them out as a culprit if they don’t fail after being heated. Make sure to get them very hot. Do yourself a favor while you’re waiting for a tank seal and find a buddy who has a heat gun and test your coils. It will take all the couple minutes the test and then you will know if it is or isn’t a defective coil. It’ll make you at least feel better about spending your time and money rebuilding a fuel pump. If you can open up your brain box in your CDI box. You can always try to very lightly apply heat to it as well. If it kills while you’re lightly applying heat there’s your answer...same with your coils. You don’t want to get the CDI/brain box too hot in fear you might melt some of the soldered connections.


Let me know how it turns out.

[BamaNapper]

Tripplebeards… this model machine doesn't have an electric fuel pump. It's a mechanical pump operated off pulsing manifold pressure. No humming to be had with this one.

Personally, if I was questioning whether my coil (there's only 1 on this machine) was failing due to heat I'd get it away from the heat source and go for a ride. That way all other aspects of the experiment would be the same. If it pooped out with a heat gun, Touchdown! But if not, is it because the heat gun was too small? Was the engine at idle pulling the heat from the coil? Or is it because it's a fuel or other issue after all? Instead I'd lift the coil off the engine. Some coils are wired where they don't need to be mounted, others do. I'd try hanging the coil in free air with a couple zip ties, then make up a short jumper wire to ground it to the engine if necessary to get the sled running. Then go for a ride and let that MN air keep the coil nice and cool.

But the fact that the OP'er says there appeared to be spark immediately after the engine died kind of reinforces my suspicion of a fuel issue.

[Jniedbalski]

Most coils are mounted against the fly wheel. So you can’t move it. I bet it’s the coil. All my two cycles if there over 12 to 15 years old the coils always go out like this.

[6bg6ga]

I'm not thrilled with heating up coils myself. I'd be tempted to go the other route and simply take it for a spin after the fuel problem has been solved. If it quits after being warmed up then simply open the hood to cool things down and when it starts again after the coils have cooled you know you have a problem there otherwise adding excess heat can be a catalyst in the coils premature death.

[BamaNapper]

It's the stator that's mounted behind the flywheel in a CDI system. Magneto systems are the ones that tend to have coil, etc behind the flywheel. The stator feeds the CDI module and the coil. the CDI then fires the coil. The coil on this machine is a rather small one that appears to mount on the engine block with connections from the CDI module and has the two spark plug wires coming out of it. It looks as though this is one of those engines that fires both plugs at the same time off a single coil. Seems strange, but as long as the ports on the off cylinder are closed off when it fires I guess there's no problem doing it this way. Then again it might be 2 small coils in the same package.

[jonp]

+10 Tripplebeards!

Snowmobiles are better used in numbers! More people to dig you out after you get stuck! More chances you can ride double back home or get towed in!

They are expensive to feed non acohol gas to as well.

But when things work, they are lots of fun!

Three44s

Oy! Did I find that out one night. Decided to take my Polaris 700 Snowcat out after the groomers about midnight on a balmy -20 night and get it stuck 20 miles from a road. Either wait several hours for them to make the circle, walk or get it out. Got it done but my back has never been the same.
That machine was a beast. Fastest sled I've ever run. About 120mph across a lake still picking up speed and blowing a Bomardier off the trail. Going slow on the trail before due to the bumps and the flatlander was riding me. Got to the lake and he went off the stakes to pass and gave me "the look". You know, don't know how to drive get out of the way. First sled I had was a 12hp Bombardier with the roundnose. Great for breaking trail before groomed was a thing as even a kid could pick the whole thing up and turn it around but of course he didn't know that. That long track ran him right over. Great machine.

[pmer]

Thanks again for all the tips. I didn't get to look at it yesterday and today is the TOWMBO birthday. So I should be able to get to it tomorrow.

It has a stator under the recoil and a ECM. Those 2 would be spendy to replace. The coil is up and away from heat sources not far from the fuel pump.

No battery or starter.

[Plate plinker]

If you haven't run it with the gas cap loose. We had machine that had this problem and it was fine until the tank need to draw down. After that who knows let the fun begin.

[6bg6ga]

One thing missing with most snowmobiler's and that is unfortunately common sense. More than I time I watched as paramedics searched for some unfortunate that smashed thru the ice on a frozen river at a high rate of speed. At 120 mph when you crash the ice isn't for the most part forgiving and its kinda like hitting a cement wall. So, I urge you to employ a little common sense and try not seeing how fast it will go. I have a cousin that hit a farm fence the barb wire kind at 90 miles an hr. He is still alive but somewhat diminished.

[Tripplebeards]

Moving the coil isn’t going to help it... The coil heats up by itself...it’s an electronic part. Adding heat to it just speeds up the process to test it to see if it’s bad. If one does not have enough common sense to realize how much heat to, or not to, apply then take it to a dealership and have a professional test it and fix the sled and move on. Through the last 25 years of working and managing auto service centers I’ve watched several defective coils being diagnosed this way by technicians. It’s literally the only way you can test them instead of just throwing parts at it. Good thing the dealer didn’t sell him a coil as well or we’d never know which parts getting randomly thrown at it fixed the issue. I’m done trying to help, good luck with your project.

[6bg6ga]

Moving the coil isn’t going to help it... The coil heats up by itself...it’s an electronic part. Adding heat to it just speeds up the process to test it to see if it’s bad. If one does not have enough common sense to realize how much heat to, or not to, apply then take it to a dealership and have a professional test it and fix the sled and move on. Through the last 25 years of working and managing auto service centers I’ve watched several defective coils being diagnosed this way by technicians. It’s literally the only way you can test them instead of just throwing parts at it. Good thing the dealer didn’t sell him a coil as well or we’d never know which parts getting randomly thrown at it fixed the issue. I’m done trying to help, good luck with your project.

I don't agree that heating up the coils is such a good idea without the ability to monitor the heat and temperature being applied. Sure, it might help diagnose the problem or possibly aid in the need to replace the coils. I am a firm believer that the problem will rear its ugly head if it is a problem when the sled is heated up.

[.429&H110]

I don't live in North Pole anymore. I visited Tucson and 70F in December is the medicine for arthritis. Every Alaskan has a sled or two, so I bought a 95 indy 650 air cooled from a coworker. Would start up and run a few miles, and die dead. I broke the struggle string and dragged her into the garage, rewound and fired her up. Ran all day. Next day. No.
So I dragged her into the garage, and drained a gallon of water from the gas tank.
Was no gas in it, when I bought it. Only water. But how did it start?
With clean gas never another problem. The thing would scream.
Had an eject button, sourdoughs told me where it was, lucky I wore a helmet.
Let go the throttle, you are going a long ways in the air.
-20F with a 60mph windchill makes Mars look warm...
I like Arizona, no shoveling sunshine. Cold is for the young.

[Three44s]

One question seems to come to mind here...as altitude increases doesn't the mixture get richer with a carb? Maybe I'm remembering incorrectly but I thought I remembered my father having to lean change to smaller carb jets as altitude increased in the car many years ago..................

As you gain altitude the fuel must be reduced to match the thinner air. Without adjusting the carb the engine blubbers and fouls plugs.

If the carb is not readjusted back to the lower altitude setting when the sled is run back in the lowlands the engine will be running excessively lean.

Lean fuel mixtures cause excessive heating to the point of inviting burning up pistons and seizures. Without an apparent symptom few folks will reset the fuel mixture when it is too lean because the outward indication from the motor is that is running (deceptively) really .... really great ..... for a little while.

Best regards

Three44s

[pmer]

In 1969 my dad won a a Ski Doo snowmobile and that was how he into the sport. From there into the '70s he and his buddies started a club and worked to make trails in the area. It was a lot of work securing permission from land owners and clearing trails. One part that was fun for me was I got to drive sitting in front of dad from about 7 or 8 years old. Most of that was on a 1971 Ski Doo Nordic 399cc. Some of the sleds back then were Sno Jet, Chapparral, Ski Whiz, Raider, Mercury and Scorpion that were in the group among the ones common today.

Currently we have a 2000 Polaris, 2001 Ski Doo and a 1971 Artic Cat Panther along with this 2013 Polaris. Before the '01 Ski Doo I had a '96 Polaris Ultra, a 680cc triple, it was a fast sled and ran good. A wreck that comes to mind for me was on the Panther going across a lake. I came out of a creek channel that was feeding the lake I just started to open it up and hit a old chunk of ice from a spear fisherman. It wasn't marked like they are supposed to be and it was obscured enough to make it hard to see. I hit it square and was bounced off the machine, bumped my knee on the way off and had to run to catch up to the snowmobile because it was heading away at slow pace!

I haven't used the snowmobiles very much these last several years for other than making trails for cross country skiing on the farm. Using traditional skis and going in the track of the snowmobile. So I'm hoping to get back on the trials a little bit with a more modern machine. The teens in the house need to take a snowmobile safety course before they can go on the trails and anyone born after a certain year as well.

The gas cap seemed stuck not venting unless it only vents after a certain amount of vacuum - anyways it vents really good now LOL. Put the fuel pump rebuild kit in $8.00 and it didn't help. It has spark every time I check but I noticed the lights flicker some from idle to above idle. I guess that could be a regulator which can take out the stator. Last night it died in less than a quarter mile and didn't really get warmed up. Today I'll replace the gas and try to have some with to squirt in the cylinders if it dies again.

All I really know is it drives a little ways dies and starts with the choke on. When it dies, its both cylinders, so in other words both cylinders seem to run and die together. Has good power when running.

[6bg6ga]

I believe it has been suggested to dump the gas and I would have done that first thing. I would also drop the bowels on the carbs and check for junk in the bowel or the float not dropping to let gas into the bowel. Always start with fresh gas in the tank and always check for varnish and other junk in the carb bowel.

[Three44s]

I have never fooled with them but I wonder if there is a check valve on the engine for the vacuum hose that runs the fuel pump? I would unhook the fuel pump output right after the sled dies to see if it is still pumping fuel.

Beyond that I would change the hoses. Looks are deceiving.

A blockage in one carb would make the sled die one cylinder at a time so I doubt that is a carb problem. You should be able to open drains on each carb bowl to ascertain that they are sufficiently filled with gas. That said I would also dump the fuel and remove the carbs and boil them out and kit them.

Three44s

[pmer]

253367

I road it for an hour today! I ended up taking the gas tank off and flushing it out because it had bits of deteriorated fuel line in it. This also lead to what seems to be the cause for the sled running out of gas. The seller said he replaced the internal fuel line with the screened metal fitting that picks up gas. Well the hose for the fitting is curling to the front left corner of the gas tank.
Looking at the picture you can see the tank sits under the seat. It has no baffling so when you get on the throttle AND if the tank is on the low side all the gas goes to the rear end of the tank and away from the fuel pick up.
With the tank being that color or opaque I could easily see the gas rushing away from the fuel pickup.

He might've used a standard piece of fuel line where maybe Polaris calls for something that goes more straight to the rear side of the tank. There was also a bare wire under the tank too.

It's by no means new and still has some bugs but hopefully this issue is figured out.

[Lloyd Smale]

you have three meter jets I the carb. The high speed jet is what controls 3/4 throttle and above. it is starving for gas. Be it from a worn fuel pump, plugged filter leak in the line ect. Enough fuel is getting into the bowl to feed you idle and pilot jets but not enough to feed you main jets. I doubt its a carb because both wouldn't be doing it at the same time. Be very careful running it that way because if its running out of gas with the throttle open your going to go lean and possibly detonate and burn a hole in a piston. Those sled were cross country race sleds. NO oil injection and slightly higher compression that requires premium fuel. The compression makes it more apt to denonate and especially if you didn't know you were suppose to use premium in it. Id even consider looking in the spark plug holes to see if theres any piston damage. I had a sled I burned down in a race. Even with a hole in the piston it would start and run 50mph. But anything over that it almost felt like it was starving for gas. When we took it apart it had a quarter size hole in one piston and the top ring land was cracked in 4 places. Old race sled could have been run hard and put away wet and even wiped a piston and the guy decided to pass it on rather then fix it. Ive seen sleds with broken rings act just like that too. Just for grins look at your plugs. they should be a light chocolate brown. If theres flecks of aluminum on them you have troubles. IF there very light brown your lean. To check them run wide open let off the gas fast and shut off the key and cost to a stop. Look the tops of your pistons they should be a uniform chocolate brown too. A rifle bore scope works great for checking them.