WHAT CAUSES WHITE RESIDUE IN EXHAUST???? Other than coolant Leak???

BIG-BALLZ

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Heres the scoop!!! 2006 Ski-Doo Summit 800 151, Just freshened it up with new top end (2000km) and such, new o-rings etc...
Went on our first trip of the year, Ran Flawless!!!! Pulled like a Train!!!! Ate a lot of fuel but thats in its nature....
Came home and started to look over sled a bit, coolant level was good, seemed like it was using proper amonts of oil...
Pulled off the can to see what the Exhaust looks like, and noticed the internals of the can, along with the inside of the pipe is covered with this DRY, WHITE RESIDUE....
Kind of struck me as odd, mind u I never really notice it before either... The film isnt loose or anything, it seems like its "Baked" on...

The only thing I can think of is maybe coolant leak... But I have no coolant loss...

This trip however, I did decide to try to use a "20:5 Premium to AV Gas (100Low Lead) mixture... Could the AV gas, being a Dry fuel, cause this colour change in my exaust pipes????

HELP!!!!!!!!!!!!!!!!
 

BIG-BALLZ

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yes and also did you check to see how your sled was running? you say it pulled like a train perhaps it was running a little too good on the lean side.

check your plugs at all?

No Unfortunately I did not get to check Plugs, I had to leave the sled at my Dads in Edmonton... So your saying the AV Gas and running optimal will cause white residue???
 

maxwell

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No Unfortunately I did not get to check Plugs, I had to leave the sled at my Dads in Edmonton... So your saying the AV Gas and running optimal will cause white residue???

never seen it myself but the etecs leave almost a light grey coating on the exhaust system simply because they run on the edge and use minimal oil.

just my best guestimate that burning hot and the fuel combination. if you havent lost any coolant it cant be that.
 

BIG-BALLZ

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never seen it myself but the etecs leave almost a light grey coating on the exhaust system simply because they run on the edge and use minimal oil.

just my best guestimate that burning hot and the fuel combination. if you havent lost any coolant it cant be that.

Does adding Av gas make it run leaner??? Or your purely Stating this towards Etecs , not powertecs?
 

BIG-BALLZ

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Heres the scoop!!! 2006 Ski-Doo Summit 800 151, Just freshened it up with new top end (2000km) and such, new o-rings etc...
Went on our first trip of the year, Ran Flawless!!!! Pulled like a Train!!!! Ate a lot of fuel but thats in its nature....
Came home and started to look over sled a bit, coolant level was good, seemed like it was using proper amonts of oil...
Pulled off the can to see what the Exhaust looks like, and noticed the internals of the can, along with the inside of the pipe is covered with this DRY, WHITE RESIDUE....
Kind of struck me as odd, mind u I never really notice it before either... The film isnt loose or anything, it seems like its "Baked" on...

The only thing I can think of is maybe coolant leak... But I have no coolant loss...

This trip however, I did decide to try to use a "20:5 Premium to AV Gas (100Low Lead) mixture... Could the AV gas, being a Dry fuel, cause this colour change in my exaust pipes????

HELP!!!!!!!!!!!!!!!!


Heres a Pic of the can.... If it helps anyone out....

DSCN1686.jpg
 

BIG-BALLZ

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Since I got the Attention of the Doo Dudes, I gots another question with a pic to go with.....
This picture is taken from a REMAN shortblock from brp....
Around 600kms on the Isoflex...

Almost looks like the Isoflex hardened, Compared to new ISOFLEX right out of the Tube....

DSCN1684.jpg What ya all think???? Issues? Or normal for ISOFLEX to do this??
 

pfi572

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Yes it is Av gas doing this and not sure why . On my 1107 triple i ran av gas and pipe looked the same. Someone that knows why may pipe up and let us know.
 

007sevens

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The reason why is that AV gas burns cleaner and hotter. You can run fat on AV gas and cause a reburn in the pipe making it as white as paper. Your pipes are bang on and if you check your plugs they will be light brown to white in color which is right.
 

BIG-BALLZ

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The reason why is that AV gas burns cleaner and hotter. You can run fat on AV gas and cause a reburn in the pipe making it as white as paper. Your pipes are bang on and if you check your plugs they will be light brown to white in color which is right.

So... I'm spending all this time worrying about my Motor, turns out its running about as good as I can get it??? Well that's a huge relief!!!! I'm new to the REVs and how to read Plugs and such... I know some people do a "Burn Test" which entails doing a WOT pull and killing the motor while still WOT... any accuracy to this, or how would I get an actual ACCURATE plug reading??

Thanks!!
 

007sevens

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So... I'm spending all this time worrying about my Motor, turns out its running about as good as I can get it??? Well that's a huge relief!!!! I'm new to the REVs and how to read Plugs and such... I know some people do a "Burn Test" which entails doing a WOT pull and killing the motor while still WOT... any accuracy to this, or how would I get an actual ACCURATE plug reading??

Thanks!!

You can do a WOT pull and idle back down and still do a plug check. Plugs don't change color that fast. light brown to dark brown your fine. white to extra clean is bad. Keep in mind when using lots of AV gas your plugs will be cleaner, light brown to clean. yes it is accurate, A good way to know how your engine is running.
 
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