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The Downfall of the 1000 SDI ???

92462 Views 384 Replies 35 Participants Last post by  Daag44
When I first joined DooTalk there were a number of owners who took a special interest with the 1K and we tried our best to understand this beast. We were all fighting to figure out the reasons why these behemoths were failing and how to avoid the aftermath. At times we created such a ruckus that it eventually drew us apart even further. It got to the point that it turned into a choice between BRP designed the engine to fail, or they were not running right. To me this was the demise of the 1000 SDI on the DooTalk forum.
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Hello new to this sled, so do you guys recommend running the XPS mineral oil for the injector oil?
The big end rod bearings likes it.
Stuck Injectors

On occasion we get to see the brilliance from different owners tackling the various problems with SDI injectors which crosses all three engines, the 600, 800 and 1000. Below is a link to one of those.

Stuck Injectors
Should you measure the Run-out on a Rebuilt Crankshaft???

This is how the story goes. Owner buys a rebuilt crankshaft from a professional that was said to be straightened to under two thousandths of an inch and it goes straight into the crankcase without checking. Sure some owners do check, but maybe one percent and likely far less into the tenth of a percent.

The stories are endless, but here are two. The first one is my own from last week with the rebuilt crankshaft having 1 thousandth of an inch on the mag side. Sounds good? The pto was at a whopping 24 thousandth of an inch! It took some coaxing just to get the crankshaft to be measured, and a little more to do something about it. I handed the owner a ball pen hammer and chisel and said to start whacking lol It took many shots to get it moving a few thousandths, but it was important to me to have the owner experience doing the work to better understand it. Once it had reached six thousands of an inch, I asked to switch places so that I could whale on it and we reached under two. This story is not about how to straighten, but rather about what really happens in engine builds.

The second story is one I was told last evening. The gentlemen follows this forum so I will let him recount it if he chooses. But I will say that the vast majority of owners who do not measure is because they do not believe they can, and even if they could they do not believe that they can do anything about it. To me this is a fundamental problem.

The subject of rebuilding a crankshaft is complex, but the work that we as owners who take on the task of rebuilding our own engines is relatively simple and far easier then rebuilding a skid. The work is also cleaner and faster.
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Electrical Troubleshooting


1. Forget about needing to be a pro.
2. Easier than most other work on the sled.
3. The resistance (ohm) setting is rarely needed.
4. Vast majority of problems can be diagnosed in 60 seconds.
5. Tools needed: DC Volt meter (or test light) and a second set of hands (or alligator clamps).

DC Volt meter leads:

Red on Battery Positive, Black on Battery Negative.
Red on Battery Positive, Black on Chassis.
= Shows bad contacts on battery ground strap.

Red on R11 fuse, Black on Battery Negative.
Red on R11 fuse, Black on Chassis.
= Shows bad contacts on ground straps.

Black on Battery Negative, Red on Starter solenoid switch.
Black on Battery Negative, Red on Starter solenoid coil.
Black on Chassis, Red on Starter motor Positive.
= Shows power delivery issues to starter.

Black on Chassis, Red on F8, F9 and F12 fuses.
= Shows power delivery issues to appliances.

Those are examples, but enough to troubleshoot most problems. The last one will diagnose all three relays within seconds. If I were to make a troubleshooting flow chart it would be too long to be of any use when it is mostly needed trailside. Open the hood and see if you can outline the main circuits. There are only a hand full to know, and maybe a dozen test points to remember. The SDI is in my opinion the easiest Ski-Doo to diagnose and repair. Take a real example: Sled is running great, stop it for a break, then no start and no gauges. Discouragement sets in about two minutes, so you have 60 seconds to diagnose the problem, and another minute to fix it well enough to run. I realize that you probably just want to replace the relay, but it's -20C (-4F), the relay contacts are stiff, the plastic tabs that hold the relay socket are cracked and will let go when plugging the new relay, the fuse box will need to be unclipped to hold the socket from underneath, and the fuse box clips are about to break too. I am inadvertently using an example that leads into a more complex subject of what's best to do in what circumstance, but the goal of this post is to show the value of troubleshooting fast and effectively.

Do me a favour by taking a few minutes now and then to focus on the battery area and fuse/relay box. Start with the Red/White wire and follow/imagine its path. Then move to the Violet/Red that starts at the VRR. Start with those two and learn them well. The further these two are understood, the easier it is to simplify the circuit down to the essence. The less that needs to be remembered, the better. Try to find the shortest way to write down the path of the Red/White wire. As a hint, there are two starting points, either the battery or the VRR.

Find one common electrical problem that cannot be diagnosed trailside in a timely manner, and fixed good enough to run without freezing your hands at -20C (-4F) with winds of 40 kph (25 mph).
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Sound wisdom! Very well done!
Question : Is it just Ski-Doo wiring that you have had issues with? Or other sled manufacturers?
I grew up in the 70s and 80s on Yamaha and currently have a couple triples. I never had any wiring issues that I can think of with any of my Yamaha sleds , The occasional T.O.R.S here and there but nothing to bad.. Really easy to figure out trailside, that being said, these are not fuel injected either.
Being fairly new to Ski-Doo and seeing how the functions of this sled operate is really quite interesting. I am a little bit surprised that Ski-Doo did not have some type of limp mode, or mapping in place when fuel pressure drops to an unacceptable level it notifies you .
I'm more than appreciate all the advice from you folks on this site absolute seasoned veterans of Ski-Doo. I'm quite fond of the shut up and listen and you'll learn something approach especially valuable when it's something I recently acquired.
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The main problem with any powersport is the size of the stator and poor connections. I follow your other questions, but can you provide any specific Yamaha sled with model and year to compare with?
Nothing to compare with one of these fuel injected sleds. Just sxr 600 and 700 triples.
Yamaha make good sleds. I would enjoy hearing more about the wiring and grounds. On the Ski-Doo SDI there is much to be desired with the ground points like the battery ground strap that is secured to the lower portion of the right footwell where snow accumulates. The VRR chassis ground is bolted to the bottom of the pan where water and coolant tend to accumulate and promote corrosion. A cleaner location for this ground would be a few inches away next to the engine ground strap.

A fuel pressure sensor would be helpful for any EFI sled. Polaris added one to their Patriot in 2019, and a fuel temp sensor. I wonder if the fuel mapping adjusts with fuel pressure change. When it gets down to -25C (-4F) we have noticed a higher fuel pressure on the Ski-Doo SDI.

2019 POLARIS 850 PATRIOT: An In-Depth Technical Preview
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I have been told that. It's supposed to keep rave exhaust vales clean longer.
Cylinder Finish (Honing)

This is the missing ingredient for our two strokes. A few years back I picked-up what I thought was some cool info with a fancy mirror finish. I took a picture and brought it to my local plating shop in Quebec to ask if he could do the same on an 800R I was working on. He looked at me and shook his head. The shop owner did his best to explain what I was showing him was not the way it should be done and how he had learned the art from what he measured on OEM cylinders with the use of a profilometer and from other sources skilled in the art.

I did leave the Quebec plating shop smarter, but unfortunately I was not yet convinced. So I called [email protected] and recounted my experience. When the next phrase started with <Charles,> I knew that I was in trouble lol The cool part is that they both employed a profilometer and did the leg work to achieve the best results with NiCaSil plating. Scott gave me enough to figure it out on my own, hence the video I found which I asked him about before posting it here.

Essentially the honing is the most important part of the cylinder finish to retain the oil and seal the rings, and of course other things like seating the chrome coated rings and oil flow. I am not all that technical, so I added a video below to better explain the importance of honing.

Affordable vs Backyard Rebuilds

At least by that time I had already learned from my own experience that re-rigging an engine was poor work that fell to the backyard standard. I prefer the affordable rebuild standard which is one that I have coined for the best work we can do in our home garages. Some times we are stuck using the backyard standard, but at least we can set our expectations accordingly.

The standard is more important to repair an engine failure. There are off-trail sled owners who replace the pistons and rings after say 3,000 miles with success, but these are working engines with first class OEM cylinder finish. If you are used to seeing 150-160 on your compression gauge for a newly plated cylinders and new pistons/rings, and then see 125-140 with a cheap ball or finger hone job, then you will know what to expect... Personally I believe the excess blowby is not good for a two stroke, and too far uneven compression is even worse.

The video below does not focus on NiCaSil plating that we have in our snowmobiles, but the company does do work with this plating in the automotive world. By the way all the newer G4 2S and 4S sleds have a plasma steel coating that BRP has developed over the years. I need to dig a link for this that explains the advantage of a superior porosity, but the key thing for us is knowing the NiCaSil or similar type plating is perfectly fine as long as the finish is appropriate. Note the special drawer of abrasives for hard coatings shown at the 10m50s mark of the video.

Total Seal Youtube Channel

Below is a Webinar type video from Total Seal that goes further in depth. At the 1h30m50s mark and to 1h34m11s it covers a question on NiCaSil plating for two strokes!

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I have a chance to aquire a 2007 mxz renegade 1000sdi. Looks like a nice sled, well kept, rebuilt engine, 3500 kms, $3500
Should I go for it?
I’m not afraid of maintenance and love to try this machine
I have a chance to acquire a 2007 mxz renegade 1000sdi. Looks like a nice sled, well kept, rebuilt engine, 3500 kms, $3500

Should I go for it?

I’m not afraid of maintenance and love to try this machine
My usual answer is no if the question needs to be asked, but since you would love to try this sled, then heck ya. Safest bet is to see it as a vintage sled where as long as it is clean and straight, then we deal with whatever problem comes along.

If you want to get a reasonable idea of the engine before buying, then that's something that needs to be planned ahead with the owner. Let me know if you need any insights on the can. It is something that keep meaning to cover in this topic if I haven't already.
I’m thinking I would doo a compression test anyway. My buddy bought a new 2005 summit 1000 with a 151 track back in 2005 and it stayed at my house so I got to ride it alot and maintain it. We had an issue once with an erave cable breaking so I bought all new and learned how to set those up. It was easy once you got into it. Arm pulling power thats for sure. Always wanted a shorter track version
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I’m thinking I would doo a compression test anyway. My buddy bought a new 2005 summit 1000 with a 151 track back in 2005 and it stayed at my house so I got to ride it a lot and maintain it. We had an issue once with an erave cable breaking so I bought all new and learned how to set those up. It was easy once you got into it. Arm pulling power thats for sure. Always wanted a shorter track version
A 2007 is start with a good footing. It has many upgrades to eliminate a bunch of problems that you don't need to worry about.
2007 Ski-Doo Press Kit for the Mach Z

I found this press release among my shop manuals. I am not sure if the pdf uploaded, so I copied the text below.

2007 Mach Z Adrenaline
Means Business – and Fun

2007 Mach Z® Adrenaline Highlights

  • The 21st century musclesled – power, handling and technology
  • 170 hp Rotax® 2-TEC 1000 SDI twin
  • Driver-centered RT™ platform for outstanding handling
  • Race-proven SC-4™ rear suspension
  • Pilot 5.7™ dual-runner trail skis

Snowmobilers used to have to choose between top-end speed and good handling. High
horsepower and decent fuel mileage. Power and light weight. Then the 2005 Ski-Doo® Mach Z snowmobile debuted and made these choices moot, thanks to smart design and sophisticated technology. With the Mach Z, riders get it all.

Every discussion of the Mach Z starts with its engine, the 170 hp Rotax 2-TEC 1000 SDI. Power delivery is linear and spot-on thanks to a sophisticated electronics package that includes semi-direct injection, e-R.A.V.E. exhaust valves, throttle position sensor, knock sensor and more. The system keeps the engine running solidly through changes in atmospheric conditions, even different fuel octane.

And in these times of high gasoline prices, Mach Z owners will appreciate the sled’s incredible fuel mileage – 16.7 U.S. m.p.g. [7.1 km/L] according to BRP testing. It is also fully U.S. EPA certified.

Because it’s a lighter weight two-stroke engine, the 2-TEC 1000 SDI is a major factor in the Mach Z sled’s agile handling. And it’s handling that sets the Mach Z apart from all other musclesleds. The RT platform’s relaxed driver-centered positioning makes cornering easier and quicker, as do the Pilot 5.7 dual-runner skis.

The race-bred SC-4 rear suspension with HPG shocks deftly soaks up bumps and works with the R.A.S. front suspension to enhance cornering even more. The drivetrain is absolutely state-of-the-art, with the TRA V drive and HPV Roller driven clutch delivering smooth shifting and long belt life.

Sure the Mach Z is packed with high-tech, high-performance goodies. But it is also easy to own, with standard RER™ electronic reverse, full instrumentation and the ability to add the exclusive 1+1 seat for occasional two-up rides.

In the end, it all makes the Mach Z more than just a lake runner – it is also a fun all-around trail sled that gets great gas mileage and is U.S. EPA certified.

Throw in an upgraded appearance package with new graphics for 2007, the world will know a Mach Z owner means business.

®, ™ Trademarks of Bombardier Recreational Products Inc. or its subsidiaries.


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Advertised 16.7 US mpg @ 45:1

The fuel consumption as shown in the 2007 Ski-Doo Press Kit for the Mach Z in post #357 fits perfectly with the 45:1 ratio that BRP posted on DooTalk back in the BRP corner days.

As much as the fuel consumption seems unrealistic, so is the oil consumption. As a quick reference for typical trail riding in the range of 12 to 14 mpg US, a ratio in the range of 30:1 to 35:1 will be in the ball park.

12 mpg US @ 30:1
14 mpg US @ 35:1

15.5 mpg US @ 40:1
16.7 mpg US @ 45:1

A worn oil pump will output a greater amount of oil at a set adjustment. For example, if you rely on the original 16.5mm setting, you may find it takes far too much oil, perhaps even twice as much. If the pump is excessively worn then even 18mm may be too much oil. Bigworm is still on DooTalk and repairing the oil pump. Just need to send him a PM.

Sticking oil pumps
by bigwormskidoo05

Pictures of a worn oil pump
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Looked at those pump pix.. wow, that is WORN. Needs a bronze bushing installed in the housing.
That would work. With this particular repair it gets bored out to fit a bearing.
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