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Discussion Starter · #1 ·
I recently bought a 98 700 RMK took it out once and blew the head gasket. I took it to the local Polaris shop to get the engine fixed, haven't really been around sleds all that much so thought this would be the easiest way to fix and ride last winter. Took over a month to get the sled back. Once I got the sled and went to the mountains to ride. Seemed like it was idling a little low when I started the sled to warm up. After I let it warm up for a bit I hopped on and got on a trail. The sled had lots of torque and power when I started out, then a little ways down the trail it started to bog out and would barely move, like 5 mph. I picked up the back end of the sled and had a friend run the throttle. the track would start spinning and sounds like it regained all the power. Set the sled down, got on and took off with all the power again. It would backfire most of the time right before the power loss. Called the shop and they said it may just of had some bad fuel left over in the engine from when the head gasket got replaced, just told me to put more fresh gas in and run it. Same results with the fresh gas. I usually ride at about 10,500' So I don't know if it is a carb thing or what it is so I thought I would see if anyone on here could help me out with something to try. Thanks.
 

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DId you pull the plugs to see if they were wet after it bogs down? It sounds like it needs a good carb cleaning. Im thinkin that when you lift the track and rev it up, its burnin up the excess fuel. After it has, it will run fine til it loads up again and starts to bog. Maybe a stuck float or needle and seats need replacing? I'm sure someone will chime in and correct me if i'm wrong.
 

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It also needs to be properly jetted and clutched for that altitude..
 

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do they run richer or leaner at higher elevation? I've never rode in the mountains.
 

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Discussion Starter · #5 ·
Pulled the plugs and they don't ever looked fouled, I even pulled the plugs, replaced with a brand new set and same thing. The shop told me they cleaned the carbs and set the jets and everything for the altitude I ride. Might just need to adjust them while I am up in the mountains, Im just not very good at messing with carbs.
 

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If they are adjusted for mountain riding, then they need to be re-adjusted for lower elevation. I dont think the plugs would be fouled, just wet?
 

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Discussion Starter · #7 ·
I don't ever ride in lower elevation so I shouldn't ever have to re adjust the carbs. They could have been slightly wet, but i don't exactly recall, they weren't super noticeably wet. How's the best way to know if your carbs are out of adjustment?
 

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j1s said:
I don't ever ride in lower elevation so I shouldn't ever have to re adjust the carbs. They could have been slightly wet, but i don't exactly recall, they weren't super noticeably wet. How's the best way to know if your carbs are out of adjustment?

Best way to tell if your jetted properly is actually quite simple.

Pull the plugs and look at the color.

Black means running Rich

Cardboard Brown means running nice

White means OH S$#T Way too lean.

You want to see that nice cardboard brown color or a mix of brown and black. You can also take a snake light and look at the piston was as well but the plugs are a simple way to tell.

When you blew your head gasket did it get hot at all?
What all did the dealer replace and fix?
 

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Discussion Starter · #9 ·
Thanks for the tips on carbs. It never got super hot, never even got it out of the parking lot and had to push it back on the trailer. They replaced the gasket and some o-rings.
 
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