2012 pro rmk 600 low end bog

Turblue

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I have a 600 pro rmk for my son. Has a bit of a bog on the bottom end. When you hit the throttle it's bogs then runs fine. Seems to be worse the warmer the temp. I've adjusted the belt and it's new. Sled has 750km on it ... It starts and idles fine.
 
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Turblue

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Yeah I was planning on that, was going to have a look at the reeds, possible the tps, new spark plugs, and If that doesn't work I might have to swing it by your place.
 

Turblue

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Think found issue. Exhaust valve spring rusted and broke.

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Turblue

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So I am pretty sure I’ve fixed this low end bog issue when it warm out. I what I figured. The gas is getting so hot from the coolers it causes the gas to become so hot it cavitates the fuel pump. I put reflective insulated material along the bottom and front of the tank. Yesterday was 7-8deg and worked great ....but

now for some reason the mag side plug keeps fouling...yesterday I had to use both new plugs. Runs for a couple hrs and fouls the plug. I tried changing the resistor plug to ethonal the second time..see if that helps.

Injector issue?
 

Lund

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So I am pretty sure I’ve fixed this low end bog issue when it warm out. I what I figured. The gas is getting so hot from the coolers it causes the gas to become so hot it cavitates the fuel pump. I put reflective insulated material along the bottom and front of the tank. Yesterday was 7-8deg and worked great ....but

now for some reason the mag side plug keeps fouling...yesterday I had to use both new plugs. Runs for a couple hrs and fouls the plug. I tried changing the resistor plug to ethonal the second time..see if that helps.

Injector issue?

A fuel line running along any type of heat source will be prone to vapor lock, this generally will cause a lost of fuel flow, like no fuel till cools off or limited fuel supply.
The cure is generally rerouting the fuel line or insulating it.

Fouling plugs can be cause by a number of issues, one of them is old plugs but you have covered the plug thing. LOL
You want to start with the easy cheap stuff first and most common.
The first thing i would do is determine if it is oil fouled or fuel fouled, it makes a very big difference in which direction you will go next.
 

Turblue

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Thanks ...I’ll post a picture of the plug. Very dark ....in 3 rides it’s fouled 4 mag side plugs ...2 yesterday...I was riding it just to see if I can figure it out.
 

Lund

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Thanks ...I’ll post a picture of the plug. Very dark ....in 3 rides it’s fouled 4 mag side plugs ...2 yesterday...I was riding it just to see if I can figure it out.

Sooty or shiny around the rim ?
 

Turblue

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rings are dinked. probably all flaked. time for a rebuild.
You think? It had a new motor at 750 km due to mouse infestation and has maybe 1200km. Wiesco pistons. I guess I could do a compression test and see...maybe I’ll drop it off after I try a few things and you can have a look. Frustrating forsure
 
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Turblue

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Ok here is a couple pictures of the piston wash. Mag side definitely has more wash that pto side. Also both plugs from yesterday compared to the pto side. Top to pictures are the mag side. Plug pictures the single is the pto side. I’m suspecting injector? Mileage is 1156 km

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Lund

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Oil is the issue, the plug pictures, PTO plug is oil fouled.
You might want to check the oil injection adjustment first, failing that you might have a ring issue if the adjustment is good.

It is also running rich on fuel as the plugs are soothy black at the electrodes and you have alot of wash but that is not the cause of the plug failing. The oil is killing the plug.
 
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retiredpop

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I had a similar problem on a Rmk 700. It turned out to be that the plug cap wasn't screwed on fully to the plug wire. It's hard for a plug to burn cleanly when it isn't firing all the time so you get sidetracked with possible causes. My exhaust valve bellows look about the same as yours when I pull them.
 
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