'10-'11 etec head up

sounds pretty minor, the piston thing is pretty much nil, that applies to most sleds

taylorbok said:

sounds pretty minor, the piston thing is pretty much nil, that applies to most sleds

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LOL !! It's funny how Doo boys have bashed Poo for a while over piston issues, but now that the known Doo issues are in the open, "it's pretty much nil". This is funny !!

HV..while you might be right about that, at least doo follows the very next season with an update and not 2 years later with an incorrect dimensioned piston.

High Velocity said:

LOL !! It's funny how Doo boys have bashed Poo for a while over piston issues, but now that the known Doo issues are in the open, "it's pretty much nil". This is funny !!

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I've never understood why other brand guys surf the ski-doo section. Since I like to ride ski-doo's I dont ever go on the other sections. I just dont care.

piston ring locator pins have been a problem for years in many sleds mainly doos actually I will be the first to admit it. I almost cant believe they are doing a recall,

I will admit the first time through i miss read the post i read 4000km not 2000 but either

i know of 2 also. was told in april that brp would take care of 2011s and the 2012 production engines would fitted with new pistons, sounds like they are standing behind their word thanks b.r.p. ( i-90 remko your are going to be busy )

In 30 yrs of piston changing, through all the different brands and aftermarket.....I have always trusted the expensive rotax pistons the most. Tryed others but always went back. Had way more poo, cat and after market ring location pin problems. Just saying.
Actually blamed the fuel that was used rather than the manufacters. Must be hard to keep up with piston designs with the way that fuel has been changing.

Mines on the list. I put on 2900km of steady mtn riding. I'll be stopping in to see my dealer this weekend to see what the deal is.

I would like to know what your dealer says. I am looking for a lightly used 11x and I dont want to have a piston problem.

Can someone link the list?

cfi it would be great for you to get a free rebuild at 3000kms. Sounds like your engine ran fine but a refresh with better parts would be nice.:face-icon-small-hap

So will they not do the update if you have fewer miles on your sled?

Its a recall/update deal. Warranty covered.

Even if you dont meet the criteria I would be pushing your dealer to take care of you and get it done.

I have looked at a couple etec motors that did this. Skidoo has had plenty of locating pin issues in the past. I lost an R motor doo too this. Crown temps come up a bit too high and out they come. The etec is especially prone too this issue because 1) The pin is mounted above the ring 2) They dont run fuel through the case too cool the piston from underneath and 3) Its a big heavy piston that is subject to big expansion rates

This is a big recall.. Props to BRP for putting out the bulletin..

Really not surprising, though.. HUGE thick single ring pushing on a small pin all day.. Big things always eventually win over little things...
Remember last season and even this Summer, how the BRP piston was the best piston without failures.. and now this...

The fact is.. this SUPER thick ring is just a plain poor design.. They need the greater surface contact to HELP with heat dissapation.. BUT, it is not working well. It is too much mass concentrated in one area (end pin).

If you look at my website you can read why I think they use the single ring. LINK-->> RING THEORY. You get massive drag and friction and the crown gets heat soaked and the piston will fail.

The ETEC has had many reports of engine failure.. especially in the mountains.. Please remember.. just because you do not hear it on DT, does not mean it has not happened. Contrary to popular belief, MANY snowmobiles have never even been on DooTalk.. hard to believe.. but true nontheless

The fact that there is NO fuel entering the bottom end to cool the Crank AND Piston is a major issue IMO.. Fuel is the #1 cooling source for a 2 stroke engine. remove it (like the ETEC does) and the parts heat up in a hurry.. Hence, the super smart ECM that is constantly monitoring heat and making adjustments to try and cool down (ie remove power) the internal components.. There is a reason why the ETEC is running a lower RPM and why it was lowered even further for 2012..

After this update, expect your 2010.5-2011 ETEC to run at the lower rpms and at a lower power output.

Installing a GOOD dual ring piston will help out greatly.. but the bottom end will still suffer from lack of fuel passing over the internals and cooling.

Funny,last year how that new BRP thick ring piston was the cat's Meow .. Now it seems it is more of a cat's scream..

The bottom line is.. that ALL this ETEC running is still in its infancy.. After 1 or more MOUNTAIN riding seasons , the problems will start to appear (like they are now). The testing method of sending a company rep(flatlander) to ride the mountains for a month and then calling it all good.. simply does not work. well.


The stress put on these engines under TRUE mountain riding conditions is very heavy.. The engine should be tested in the TRUE enviroment it will be subjected to.. not a scaled down version..

Again.. good on BRP for recognizing this issue and taking the steps to fix it..

Ask yourself this.... How much time (REAL RIDING TIME) do you think do you think BRP has on the NEW piston?? Answer?? Slim to none.. How good is this new piston going to be since it has no real time on it?

RKT I think you are greatly exaggerating the problem.

diamonddave said:

HV..while you might be right about that, at least doo follows the very next season with an update and not 2 years later with an incorrect dimensioned piston.

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Touche'

Powderboy said:

I've never understood why other brand guys surf the ski-doo section. Since I like to ride ski-doo's I dont ever go on the other sections. I just dont care.

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yep.

BTW, what pistons are in the 09 800r motors? Single or dual. Is there an issue with those?

winter brew said:

"Ask yourself this.... How much time (REAL RIDING TIME) do you think do you think BRP has on the NEW piston?? Answer?? Slim to none.. How good is this new piston going to be since it has no real time on it?"

RKT, do you feel there are different forces at work that would relate to ring pin failures when an engine is in a sled vs the endurance testing done in controlled conditions?
Doing destructive testing for a living on a wide variety of products, we put things through much more torture in a lab than they will ever see in service.
It's my understanding the new piston is identical to the old with the only change being the locator pin....or so I'm told. What other changes are being made that lead you to believe the power will be lower? I am hearing the opposite for '12.....just curious.

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Paul..
Great questions...

Every rider rides different and subjects their sled to different stress levels.. I have my "group" that I ride with and only a few of us pull the big chute.. So, mountain riding is not all equal in these terms..

The dyno "hour tests" durability tests that the manufacturer's use is great testing but does not factor in ALL the parameters that are at play in a realworld situation. Take the 07 800R for instance, why was the case tolerances not caught in the durability testing? 08 testing.. why were the bad rods not caught? But back to the other players.. the durability testing has not tracks spinning, elevation changes, temp and density changes (maybe they can simulate this to an extent).. and just overall twisting and vibration of the engine and chassis.. there is simply not an easy method for simulating this sort of thing.

As for the new piston.. simple.. the #1 cooling agent at work in ANY 2 stroke engine IS the incoming fuel charge entering the lower end. The ETEC has eliminated this agent.. this WILL cause premature engine failure and accelerate component wear..

There is a reason why the 800R (2007) ran at 8500 rpms (stock) and the 2008-2010 800R at 8150 .. Now, the ETEC runs , initially, at 8000 rpms and now 7900 rpms. WHY? because lower rpms WILL always LOWER crank bearing, rod and rod bearing stress levels. This all relates to the ABSENCE of cool fuel entering the crank. So, lower rpms and this will alleviate SOME of the stresses at play in the crank.

The piston will keep getting hotter and hotter every revolution . this hot piston heats the lower end components every time it passes there.. So, the hotter piston (single ring vs. dual) contributes to the stress and heat on the crank.


Simple math and engine building formulas.. you can not EVER make more HP at a lower rpm on the same engine UNLESS the torque has been increased.. Maybe they have increased the torque at 7900rpm from the previous year engine..but I suspect they have not.

Kelsey