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03 800 Running on one

OFT Racing

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I took my 03 RMK 800 out on sat ice fishing and to just get it out for the first ride of the year to make sure everything was working good and about 100 yards down the trail the pto cyl quit fireing and has not fired since. I have not ben able to check compresion yet but from what I can see and feel it does not seem to be the problem. It does seem to have like a ticking sound like a gasket leaking but I cant locate anything. Also this sled has ben very picky for me and I have had many days that it is not running up to par last season. I talk to other people with the same sled that run the same jets all year and they run great. But with mine I am re jetting all the time to try to keep it running the best I can. Any ideas? Sorry I dont have alot of info yet.
 
Check the plugs- check for spark- check compression and do a leak down test on that cylinder. If no spark at the plug-check the coil.
Keep us updated
But do the abvious first.
 
it had new plugs in it at the start of the ride then I put new ones in after it lost the cyl because it was easy to try. I switched the plug wires to see if it followed that wire and it didn't. Have not ben able to check compresion or do a leak down yet. I was just out messing with it and I knowticed my choke lever housing was broke and holding the choke at half choke so im not sure if that could have ben the problem. But the plugs looked rich and if anything the jetting should have ben a little lean but because I was not doing any long pulls or running it hard I left it. I started it on the trailer and it did sound like it was running good now but not being able to take it for a test ride anywhere near Anchorage it makes it tough. I used a IR thermometer to find out the cyl was not fireing is that the best way? The pto was constantly a decent amount cooler when I was checking it. So I may go try that again now to see if it is more even with the choke fixed.
 
its very possible the choke, i have had a tree branch pull mine on and you would think it was the end of the world, sounds like you loose a cylinder or plug, it took me a couple of times for this to happen to figure it out, slow learner.
 
my choke housing has ben broke for awhile but this is the first time I have had a problem with it. I should just replace it so it does not couse future problems. Hopefully it will run good now and the fix was that easy but my luck I doubt it.
 
Do a compression test, you can buy a tester at napa for about $30. First things I always check when a cylinder is down is spark and compression. To check spark just put the plug in the boot and hold it up against the head and see if you see blue. Good luck and keep us posted!!
 
If that sled is stock, you should not have to rejet that thing at all. Sounds like you do alot. That being the case, I would change you choke cable out first as that may be sticking in different positions each time causing the need for rejetting. Also check the rubber boots between the carbs and the engine for cracks. If you have one that is cracked or torn, it was cause a lean condition but if that were the case, you probably would have took out a piston by now if you rode all last winter that way. Start with the obvious, you have a broke choke cable, change it. If it has been stuck, you may have alot of fuel in the bottom of the motor and it may take a while to run it all out of there and clear up.
 
Yeah I am always re jettting and every other stock 800 I ride with never touches them. One day last winter I had a problem with it running very poorly about like this time and I took my power valves out, removed the carb boots, reed cages inspected and cleaned everything and checked compression everything checked out good then I ran it again and it ran decent but not great. The sled does seem like its always rich so hopefully the choke cable fixes it. But any other ideas on why it would be so picky would be great. I am getting very sick of this sled and it should be a great sled.
 
If it goes rich on you, it is usaully one of two things, 1 the choke system, (which you have a know problem) or a needle and set sticking it a carb. The new carbs aren't too bad about that. The xlt's were terrible. Had to change the needles and seats every year! If the choke cable doesn't fix it, check the compression to make sure you didnt hurt the motor already. If the comp is good, open the carbs, clean them up and check your float levels. Good luck.Let us know what you find.
 
Ok I replaced my choke cable now I would really like to take it out for a ride and see how its running. I cant tell with it on the trailer. Another question is that my temp light is on even when I justy start it up so I figured the sensor is bad and put a new one in but the light is still on. Ideas?
 
Just a thought here, but i have seen this before and they really do run like crap. Try checking the diaphram in the variable exhaust on that side. Though if they go bad they will start to make a mess of oil out the front. I'm not sure if you KNOW the cylinder itself is down or not but this will make it run like crap if you get a hole in that diaphram. Buddy of mine had it happen twice last year and kind of ruins your day of riding. he carries and extra one on him all the time now. Just a thought since you weren't positive on the spark and compression part of it.
 
Okay I was able to take it for a little test run tonight and it is still a one lunger. What I have checked so far is spark, and visually checked my reeds through the boot, inspected the boots. I am going to run and get a compresion tester right now to check that also going to check my ves and pull my reeds out to make sure that is all good. Another thing I knowticed is some strings from a blown belt raped inside my clutch so I was wondering if my pto crank seal could be bad? I am going to have to have my clutch poped off to get that off there but I can check for a bad seal by spraying some carb cleaner down there while its running right? I will post the results of the compression test. Thanks again guys.
 
Okay the ehaust valves look good as well as the reeds and carb boots. I have the carbs off now im going to look into them. Any suggestions???
 
I am stumped. I took the carbs apart cleaned and inspected them the floats are working good everything is clean. I have cleaned and inspected everything else I can think of. I ran it for a half hour let it get good and warm and clean out any excess fuel still running the same. I sprayed carb cleaner on the pto seal while it was running, no difference. Im getting frusterated, anyone want a 03 800
 
Mine did the same thing, ended up being the VES, the valvle stuck and had a hole in the bellow at the same time, wouldn't run for crap.

Not that this helps but I had nothing but problems with my 03 800 until I tore it ALL the way down, put the Big Boy Bearing kit on, new jugs, new pistons, and walla, ran like it should. Hope it doesn't come down to that for you.
 
Thats a summertime project not a begining of the riding season project! I checked the Ves and everything looks good.
 
When idling it 's running on both, will mean compression is good.
So when reving higher under load it starts miss firing and running on one.
If it was fuel mixture you would feel it bog first and lots of smoke.
If it is electrical ( which I would guess) you have changed plugs not just once ( some times new plugs are bad) the next would be plug wires/ coil pack
inter change them after checking which side is not firring , to see if now the other one now fires. Lastly the stator ( which I think is failing) they are known to go , and cause just that symptom.

Good luck.
 
Have you changed your spark plug boots? If you did, did you cut the wire back 1/4" to get some fresh wire? The screw in the end of the boot needs a fresh tight hole (Shut up you guys:rolleyes:) If you took off your old boots & just stuck them back on the end of the wire could be stripe or corroded.
Also, do you have ANY mods on the sled, Pipe (single, twin & what brand?) Some of my pipe would really act different. Did any one else do anything to it before you owned it like port the cylinders, bore the carbs, high compression head? When you checked your floats, did you pressurize them with fuel? You can do this by filling up a small funnel with gas, fix a fuel line to the bottom of it and hold it above the carbs. Have you emptied out the bottom of the case (motor) of gas? If your choke cable was bad or bad float, needles etc, you could have a puddle of gas in your crank & it will always foul out your plugs until it is gone. Keep letting us know what you have tried. There are some good guys on here that are willing to help, but we don't have a Cristal ball. Good luck
 
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