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Spark plugs

JH@CM

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Aug 12, 2018
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Melted? Definitely need pics.
 
S
Dec 4, 2009
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Porcelain is broke and electrode fell into motor and screwed the piston and turbo. Then another one in our group has did it to 3 plugs in last two days but the electrode was still in tack.
 
C
Dec 14, 2020
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**** plugs or they're not designed to take the vibration the 850 is putting out.

If you look around, there's been a lot of people with broken porcelain. Haven't seen any dropped yet though.

I'm still running bpr9eix with good luck, have always found they are almost impossible to foul. May be time to change away from the NGK for standard plugs.


If they're stock plugs I'd push real hard for Polaris to warranty everything. They need to push on NGK to figure it out.
 

JH@CM

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I had one porcelain separate this year on my 9R at about 200mi.

Makes me wonder if there are a bad batch of NKG plugs or if there's truly something else wrong with the polaris engine causing the plugs to fail.
 

blindman

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i am thinking det like teth said but with polaris maybe the ngk guy bought the polaris pres too many bahama trips oh and of course a new 75 big screen.
 

damx

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Both 23 boost in our group had the porcelain separate on there first ride. Both pto side first, one sled stayed on 91 non eth , the other he put it in 91 eth. And it still did it again, but on meg. Side.
 

Track Man

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My son and his buddy both had 800 Polaris with Boondocker Turbos, and we’re doing the same thing? We put the SLP spark plug wires on them and took care of the problem. The spark plug wires need to be tight connection.
 

kylant

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is this a bad batch of plugs or what??
makes me nervous. never had a plug fail before
maiden voyage on the boost tomorrow...
 

AndrettiDog

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I replaced about 5-6 plugs on my 2019 850. My 2023 Boost lost a plug at about 200 miles. Dealer thinks it has to do with the super rich map on the 2023. I never had the 2019 map updated, so there could be something there.
 

Timbre

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Nov 1, 2008
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Muskoka broke 2 spark plugs in one ride on his 9R.
Gotta be something going on to cause this.
Sure does not seem normal to me!!
 

Fosgate

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A plug can break from detonation. Test your fuel to see if it has ethanol. If you run ethanol you need more fuel (ethanol mode) or it will be running lean and can detonate.

Exactly what I was thinking. Had an AC 800 that I pulled over soon as something didn’t feel right. pull the cap on one plug and oil ram down. Cracked the plug and was shooting gas/oil mix up. Found out it was detonation.

Gotta be careful filling up. Never know what you get in the first 1 1/2-3 gallons of fuel anymore due you get what’s in the hose from the last fill up. E85? Etc. After that detonation I always full up the truck first (91 oct clear gas) then pull forward and fill up sleds/fuel cans wit that same pump. Never experienced plug detonation issues again.


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JH@CM

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I did have a plug break on my 9R, and use exclusively ethanol free gas (all the pumps at the station I frequent are non-ethanol).

Wondering what else may be causing this issue besides the potential for detonation? The common backfiring of the 9R and also the general way it runs and smells feel quite rich. Maybe poo will come out with a revised map sooner than later.

Used to be that I complained about how much oil my turbo doo burned. Now maybe that's transitioned to excessive need to reaplace primary springs and spark plugs?
 
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damx

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I'm wondering if its from detonation? Mabe 94 octane or a mix of av or race gas.
 

live2beel

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I was thinking of Snowchecking a 9R. All of these broken clutches & plugs from detonation are a major bummer. If I owned one I would definitely mix a little race fuel in it . The next problem will be the piston ring locator pins falling out. Hopefully a new map can fix it if there's a lean spot.
 
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