[motohd66]

That pump will support a few hundred HP LOL.

How did you drive that pump motohd66?? It draws 12-13 amps at 12 volts.

Is it as quiet as the original pump?

Do you think the OEM pumps failed from dirt, or something else?

Plug and play. I didnt notice any sound difference. Our 2019 has used up 2 stock pumps, the filters were meh but not horrible. Im going to bet its because the first replacement pump was the 2019 part number and those had issues

 

[nm9stheham]

OK, I saw in the spec sheet that this is a turbine pump , which are quiet, so that is good. I suspect that is the type used for the OEM also. Turbine pumps are more 'touchy' for trash coming in.

I could not remember if this was a 12 volt pump or the higher voltage pumps like the ETEC. This makes it easy indeed.

Just a thought you might want to check: If like the earlier 900's, the pump ground side controlled is through the ECM. I recently was taught (thanks Daag 44 and others) that the SDI's had issues with 2 fuel pumps being grounded through an ECM output that was not up to the task of passing the higher total current and that casued soem real problems. I suspect the current is higher in this new DW pump than the OEM, So I would suggest checking the operating voltage on the ECM wire that is grounding this pump to make sure it is not too high. I looked at the 2015 900's (non turbo) and this is a brown wire to the fuel pump.

A high voltage on the ground side of the pump can cause pump performance problems, as well as put a lot of heat into the ECM driver at that output that could burn it out eventually. A few tenths of a volt is what you want to see; a few volts would be bad and would show that the driver's current capacity is being seriously exceeded.

 

[Olypopper]

To the OP, I'd recommend a scientific approach. What is your fuel pressure? I'm betting it starts off normal then drops. Keep us posted.

 

[Saber]

Seems like the black is from the motor brushes. Gas is flushed by them continuously with the excess fuel returned to the tank. Is the sock filter really plugged or just have a black appearance

 

[Wink1]

Here's my story, maybe some of these RPM fade sufferers can get something out of it. The sled is a 2017 MXZX 850 with 8000 miles on it. Runs strong and fast when everything is right. Last weekend things started to go bad for me. First I had the dreaded 7400 RPM max condition. Still ripped down low but nothing up top. I rode it anyway. No codes until the last day when I got a 1474 unable to achieve Rave position or something like that.

I could tell the motor was out of position and not cycling on startup. Got it home and did seals and cleaning. Apparently the motor went nuts at some point and broke the cable. I could not move the servo lever arm by hand at all. I did cleaning and seals, replaced the motor (ebay) and cable (had one) and synched using CanDoo. Did not change plugs since they were new this season.

Took it out and still getting top-end fade/limit but now bouncing around between 6000 and 7200 around there. Took it apart again and replaced Wix filter, put new plugs in it, and re-synched Raves for the fun of it. Made my own fuel pressure test kit and ran the sled was perfect 45 or so with very little bleed down in the first 5 minutes or so. Even put a load on it with the brake and wound it up - fuel pressure was still perfect. Sled absolutely ripped - felt like I got some previous power lost (when it was younger) back. Knew the filter should be changed, but thought probably a plug was fouled from riding it all weekend with closed valves.

Took it out again tonight and half-way through the ride it did it again...like someone else said gut instinct tells you it is starving for fuel. Read some threads during this whole thing and work on road race bikes all summer so am familiar with the sock screen.

Tore it all down tonight and YES, I would call that a dirty sock (see picture). Actual sludge on it had me wondering what was clogging it. Took a look inside the tank (see picture) and can see a spot where the "rubber" coating in the tank is wearing off/delaminating. No idea what could be rubbing there other than the pickup hose? For those considering putting the old style metal screen pickup on the end of that hose, I would think twice due to the coating on the inside of the tank. You can feel it's coated with your hand and the flaking material is very likely what the sludge on my filter sock is. This is maybe why some are having to replace this filter more often than it should be able to go. After all mine went 8000 miles before causing an issue.

I'm not sure how to fix this particular problem. If I knew of a coating that is impervious to gasoline and wouldn't further harm the rubber I would try to re-coat the area to prevent more flaking. I have a feeling I will be replacing this filter every couple seasons at least if the rubbing/flaking continues.

View attachment 2019284
View attachment 2019286
View attachment 2019285

I know this is from the 850 forum but check his opinion of what’s causing the black sludge.

 

[Judge64]

You guys may want to look at this thread. While the guy has a G4 850, his fuel sock was very dirty with a lot of sludge on it. After closer inspection....

"Took a look inside the tank (see picture) and can see a spot where the "rubber" coating in the tank is wearing off/delaminating. No idea what could be rubbing there other than the pickup hose?"


Could explain while I have gotten 5000 - 7500 on multiple XS 900 and never had to change a fuel sock or filter but the guys with the G4 / G5's are having more issues at lower mileage.

Maybe the smoking gun and not the fuel source after all?

Leaking Raves, crazy servo motor, broken rave cable...

Here's my story, maybe some of these RPM fade sufferers can get something out of it. The sled is a 2017 MXZX 850 with 8000 miles on it. Runs strong and fast when everything is right. Last weekend things started to go bad for me. First I had the dreaded 7400 RPM max condition. Still ripped down...

www.dootalk.com

 

[nm9stheham]

Yes, I saw that. Another idea on the table. The scratched area seemed to be limited, and not enough to make a repeated issue. Unless the material under the scratched area continues to fall apart.

 

[SKIDOOCHRIS]

that photo looks like the outside of the tank
every tank I have seen is white/clear on the inside
and black on the outside

 

[thinksno]

All the G4 tanks I have pulled the pump from are black inside, unlike the previous models

 

[Daag44]

These are 3 of the 4 filters that got clogged after fuel at an outfitter. I must say, I have fueled at Lac Repo many times without issue. It is very possible that a delivery truck was onsite just before we arrived, but still, there should be filter on fuel being pumped.

This is their latest pump. Is the storage tank the grey container behind it?
What was the last place you filled-up?

 

[Daag44]

I think this you tube video will help. There appears to be plastic in the tanks.

I wonder if this is an issue that spans other snowmobiles. Below is a comment from that video.

Josh A
13 days ago
Same with sidewinder. Changed filters in two of them last season and both full of plastic

 

[Daag44]

Here is a good video from Airtex for several different styles of pumps. I am thinking these sleds use a turbine style, due to the need to be quiet in this sled use. In the later part they discuss some effect of crud that gets inside the pump.

Did you mean the vane pump shown at the 2min mark? If yes, that is the one used in snowmobiles.

 

[Daag44]

IDK the actual micron rating of the Ski-Doo fuel socks but I'd make a guess in the 20-50 micron range, considering how they clog up.

I would have thought the sock pre-filter to be 100 micron. The EFI used on the ZX chassis (earliest except for a 1993 EFI) used two round plastic pick-ups with 50 micron filters that looked like a see through mesh. You can find this in the complete 2003 shop manual package in a supplemental section for the 2-TEC (or find the file mmr2tec 2003_sect.04_a) in the first few pages of the Engine Management overview section. Then came the sock filters in the 2005 REV and RT., but I don't know the micron size. Next came the XP and XR chassis which had a small sock filter which began to give problems, so the filters were changed to what I suspect was 100 micron from the X100 showing on the filter in the thread linked below. Also note Thumbdoctor's explanation. In looking at a source of sock pre-filters (Fuel Pump Inlet Filter Socks), the smallest one was 65 um, then 80 and 100. Holley’s HydraMat is 15 micron, but it's huge. It can be seen in Holley’s article titled How To Choose A Filter which also provides an explanation to the suggested micron size for a conventional sock pre-filter.

So knowing that BRP had trouble in the past as Thumbdoctor explained in the link below, and the upgraded pre-filter showed X100, it would be a good guess. Assuming this is the case, how could particles already been strained with a Twin Air 40 micron filter? I think you already explained it with the sizing it in post #62 and the one I am quoting from #72, which applies to both filters. We know all four sleds filled-up at multiple gas station, so we really don't know the condition of the pre-filters prior to the bad gas at Lac Du Repos. Ironically repos means taking a rest.

Fuel filter update 2010+ [Post #1 and #4]

 

[Daag44]

Ya....but heading to Kanawata for the night, getting gas at Mattawin on the way up and the next gas stop is Repos before hitting Kanawata......236km between Mattawin and Kanawata so rather grab gas at Repo......or go out of the way and get gas at Manawan!

The last time I went to Manawan they only sold 87. I had a carotor type fail following gas that we filled-up there, but we also topped-up less than 2 gallons at Repos before heading back to Hotel Central. The pump didn't seize until after arriving and the temps then dropping to below -30C, so that was dumb luck.

 

[Saber]

I posted the gas situation on lac repos facebook page yesterday. They took it down today so I know they read it. We will see what happens

 

[Saber]

Nice pic of lac repos gas pump. I don’t see a cartridge filter at the pump. Should I be able to see it ?

 

[EXTremist]

I would have thought the sock pre-filter to be 100 micron. The EFI used on the ZX chassis (earliest except for a 1993 EFI) used two round plastic pick-ups with 50 micron filters that looked like a see through mesh. You can find this in the complete 2003 shop manual package in a supplemental section for the 2-TEC (or find the file mmr2tec 2003_sect.04_a) in the first few pages of the Engine Management overview section. Then came the sock filters in the 2005 REV and RT., but I don't know the micron size. Next came the XP and XR chassis which had a small sock filter which began to give problems, so the filters were changed to what I suspect was 100 micron from the X100 showing on the filter in the thread linked below. Also note Thumbdoctor's explanation. In looking at a source of sock pre-filters (Fuel Pump Inlet Filter Socks), the smallest one was 65 um, then 80 and 100. Holley’s HydraMat is 15 micron, but it's huge. It can be seen in Holley’s article titled How To Choose A Filter which also provides an explanation to the suggested micron size for a conventional sock pre-filter.

So knowing that BRP had trouble in the past as Thumbdoctor explained in the link below, and the upgraded pre-filter showed X100, it would be a good guess. Assuming this is the case, how could particles already been strained with a Twin Air 40 micron filter? I think you already explained it with the sizing it in post #62 and the one I am quoting from #72, which applies to both filters. We know all four sleds filled-up at multiple gas station, so we really don't know the condition of the pre-filters prior to the bad gas at Lac Du Repos. Ironically repos means taking a rest.

Fuel filter update 2010+ [Post #1 and #4]

Yes it seems unlikely much would get past that sock/screen, but while I was troubleshooting my issue I did ride the sled for about 2 hours before the symptoms came on again. Only thing I did was blow out the WIX filter with air and put it back in before that test ride (changed plugs too but not the issue at all). I think the tank "dust" ultimately makes it to the WIX filter.

 

[Judge64]

All the G4 tanks I have pulled the pump from are black inside, unlike the previous models

Then I wonder if EXTremist in the thread about his 850 tank having a spot rubbed off is on to something?

And I wonder if additives a gas station may be adding to their tanks could cause the problem to pop up after a refill?

 

[nm9stheham]

Nice pic of lac repos gas pump. I don’t see a cartridge filter at the pump. Should I be able to see it ?

There are filters typically inside the machine, behind that large blue panel, if it is a 'fuel dispenser'. (Where the pump is located elsewhere, like at the storage tank.)

If the pump is inside too, then it technically becomes a fuel pump. I assume there are filters inside a pump but IDK for sure; they might be over at the tank.

 

[nm9stheham]

I would have thought the sock pre-filter to be 100 micron. The EFI used on the ZX chassis (earliest except for a 1993 EFI) used two round plastic pick-ups with 50 micron filters that looked like a see through mesh. You can find this in the complete 2003 shop manual package in a supplemental section for the 2-TEC (or find the file mmr2tec 2003_sect.04_a) in the first few pages of the Engine Management overview section. Then came the sock filters in the 2005 REV and RT., but I don't know the micron size. Next came the XP and XR chassis which had a small sock filter which began to give problems, so the filters were changed to what I suspect was 100 micron from the X100 showing on the filter in the thread linked below. Also note Thumbdoctor's explanation. In looking at a source of sock pre-filters (Fuel Pump Inlet Filter Socks), the smallest one was 65 um, then 80 and 100. Holley’s HydraMat is 15 micron, but it's huge. It can be seen in Holley’s article titled How To Choose A Filter which also provides an explanation to the suggested micron size for a conventional sock pre-filter.

So knowing that BRP had trouble in the past as Thumbdoctor explained in the link below, and the upgraded pre-filter showed X100, it would be a good guess. Assuming this is the case, how could particles already been strained with a Twin Air 40 micron filter? I think you already explained it with the sizing it in post #62 and the one I am quoting from #72, which applies to both filters. We know all four sleds filled-up at multiple gas station, so we really don't know the condition of the pre-filters prior to the bad gas at Lac Du Repos. Ironically repos means taking a rest.

Fuel filter update 2010+ [Post #1 and #4]

And I was just making a guess on the sock micron range, Daag, based on how quickly they seem to plug up. I wold like to know the manufacturer of these 900 fuel pumps to see if we could find out what micron of sock the manufacturer recommends.

And yes, we don't know the filter conditions prior to the Lac Repos fill up. But due to the fact that all 4 sleds started acting up soon after their filling at Lac Repos, I think it is reasonable to conclude that location was the main and final source of this particular problem. If it was an accumulation of contamination from several locations, then the timing of the problems would be more random.

And my past personal experience agrees with this totally... I have had a few incidents over 50+ years and such fuel problems appear soon after filling at a small, low volume rural station. Their fuel maintenance and practices are more likely to be not very good.