So wednesday night i got my 09 800 dragon back together after it ate a piston in togwotee and today I decide it would be good to go for some break in miles. I only made it two miles before the sled scored the pto side piston. What is wrong here? I've got a pint of oil in the gas and was really taking it pretty easy. By the way, sled was fine until april reflash and now two pistons scored in very short time. What to look for?
Need advice bad
- Thread starter Vertical Xtreme
- Start date
I didn't want to say this before because i don't think its the kits problem but I have the mtntek kit in and it still scored in a very short time.
The most probable cause is that it's too lean. With the PMS pistons, you have even less room for piston expansion, thus the scoring. I have spent way too many hours rebuilding my 800, it is going down the road as soon as I get my crank back and put back together.
I'm in the same boat! Looking at dealers 11 800 etec monday! Sick and tired of not being able to ride this thing and blowing all the time. Poo dealer says april reflash is good but i never had a problem until they put it on! Now they wont change it back!
S
skitter
Member
When you took your sled out for it's break in how long did you let it warm up, and if so what temp were you at before you took off. Just curious cause I've had my own share of problems with this same sled. Also when you put the pistons back in you might want to double check and make sure your pins in the piston were facing the carbs and not the exhaust.
Always run engine temps up to 100-110 before even touching the throttle! Pins were facing carbs not exhaust. My brother who has been a small engine mechanic for the better part of a decade put it together with me.
M
miller tools
Well-known member
flash
Not a expert but i think you have a bad flash get polaris to reflash it. i would like to look at it when you get it apart if i could. I live in boyden let me know
Not a expert but i think you have a bad flash get polaris to reflash it. i would like to look at it when you get it apart if i could. I live in boyden let me know
you have to find the problem, its lean or detinating, you have a problem. putting a piston in it is not going to fix it. its not the pistons burning the sleds down, or the motors. they are a strong motor or the turbo guys would be having a problem.. you cannot hold them in the midrange either. you have to fluctuate the throttle or you will more then likely have a problem. if you don't understand the fact that you can't hold it in the midrange I would sell the sled. (not directed towards you but to everyone who does not understand that this is how it is and its not going to change)
The problem that was there before is still there... I'd start crossing off things.
Have the injectors flow checked and cleanded.
Air in the lub system? (even with the premix)
Small leak in the TB boots.
Have the injectors flow checked and cleanded.
Air in the lub system? (even with the premix)
Small leak in the TB boots.
The problem that was there before is still there... I'd start crossing off things.
Have the injectors flow checked and cleanded.
Air in the lub system? (even with the premix)
Small leak in the TB boots.
Have the injectors flow checked and cleanded.
Air in the lub system? (even with the premix)
Small leak in the TB boots.
I hardly ever hold this sled in midrange for more than two seconds. Engine was fine until april reflash. First time was mag side this time pto. Does anybody else think maybe just bad flash? Just want to get it together right so i can sell it and walk, no run away from the poo 800! Dealer absolutely says can not flash back to old flash?
Then your dealer should pay for the repairs. I would tell you to add a PCV reguardless of what flash you have, but I think your plan of running away from it is probably the best answer.
T
theshadowrider
Well-known member
If I was you, and determined to fix it, which i would be, here is what I would do. Tear it down and start checking things like mnthorse said. I would order new throttle body boots regardless. 08 boots are notorious for separating and sucking air causing your engine to be lean. They updated the part numbers on them and the newer ones seem to be better. When you have it torn down put dual egts on it. They are worth the investment and will help you diagnose problems along with helping to preserve your engine. I would also check out your oil system. Has it been taking oil? Also like stated before add a fuel controller. I know these seem expensive but if you are going to keep it they will save you in the long run.
I have a PC5 but slp doesn't have a map for the april reflash and said they don't support it so I haven't used it since the april reflash. Sled is an 09 and the throttle body boots are perfect. No air in the oil lines and hard to tell if using oil as i've only driven a total of 2.5 miles in two burn downs. the exhaust valves and the spark plugs seem to be really hot looking. Brother says not enough fuel and looks like lean condition.
T
theshadowrider
Well-known member
What about the cooling system? Do you recall what your temps where when it went down? Did you feel the tunnel and see if it was warm when it went down, or did you make sure to bleed the coolant system before going out? Just trying to brain storm with you.
I would re-flash your ecu to the flash recommended by your fuel controller manufacturer and make sure to run it although this doesn't seem to be the cause. Can you give more history on the sled? Where you running the PCV with different flash and then the sled went down, then you reflashed the sled and put the fix on it?
Here is an interesting post on another thread.
"we had a sled that went down down repeated times time last spring so we thought ya it has to be fuel so we bought efi box and a 02 sensor to find the lean spot, but the first ride out his year it went down within 10 miles of a brand new engine with 02 readings of 11-12 now that tells you that it isnt fuel now if you have ever looked at a piston that has been cold seized it has the scores on the side of it, same as the dragon pistons we put the redneck kit on that sled and it has been trouble free since it was installed at 400 miles since then it is extremely nice to ride with out having to worry about we are more than convinced that it was the problem and not fuel"
I would re-flash your ecu to the flash recommended by your fuel controller manufacturer and make sure to run it although this doesn't seem to be the cause. Can you give more history on the sled? Where you running the PCV with different flash and then the sled went down, then you reflashed the sled and put the fix on it?
Here is an interesting post on another thread.
"we had a sled that went down down repeated times time last spring so we thought ya it has to be fuel so we bought efi box and a 02 sensor to find the lean spot, but the first ride out his year it went down within 10 miles of a brand new engine with 02 readings of 11-12 now that tells you that it isnt fuel now if you have ever looked at a piston that has been cold seized it has the scores on the side of it, same as the dragon pistons we put the redneck kit on that sled and it has been trouble free since it was installed at 400 miles since then it is extremely nice to ride with out having to worry about we are more than convinced that it was the problem and not fuel"
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Cooling system was bled of air before the ride. Was reading 127 when it went down. Around thanksgiving last year dealer put the april flash in and then january in togwotee it siezed half mile down the trail. Last week put in the PMS/MTNTEK fix and within a mile or so siezed again. Never had the PCV on with the april flash, only last season with the old flash. Everything leads me to believe bad flash but dealer says april flash is awesome?
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theshadowrider
Well-known member
Logically is seems it would be the flash, but I do think that there is something else going on with the fact that it seezed so soon. What told you that it had scored the pistons, or was it a complete seize and motor died?
T
Trenchmaster
Well-known member
When was the fuel filter last changed?
