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Discussion Starter · #1 ·
Hi Guys, i am swapping a 2000 model mxz 600, rotax type 593 engine for a 2002 model legend 700 type 693 engine.

I ran into a problem with the MPEMs i was going to run the mxz 600 mpem but the plugs don't match up. The mxz 600 plug from the magneto is triangular and the one on the legend 700 is square.

The legend engine had DPM, which i have deleted. Is there a MPEM without rer or dpm that has the square plug to suit the legend 700 engine.

Any help would be appreciated with this, thanks.
 

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That '02 700 Legend has a newer 360w electrical system... my advice would be to either switch the stator and flywheel to the 600 stuff or switch the sled over to a newer MPEM and harness. You could get RER by switching the sled over to the newer system.
 

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I would go the route of the stator and flywheel that match the chassis/mpem, but you should be able to use the legend 700 MPEM even without the DPM not being there. The engine should run without the dpm solenoid or airbox sensor plugged into the MPEM.
 

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Discussion Starter · #4 ·
Thanks guys, the 360w stator sounds like a good thing to have.

I did see that the 700 has twin ignition triggers and the 600 only has one, if i use the 600 stator set up on the 700 would that have a negative effect?

So from what i am reading here i can buy a 700 MPEM and run it with the dpm disconnected. Can someone explain to me what exactly RER is? and why is that a good thing to have?

Can i use the 700 MPEM and just leave off both the DPM and RER from the MPEM?

Sorry if these questions are a bit silly but i have no idea when it comes to snowmobiles.
 

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RER is Ski Doos electronic reverse, there is another trigger in the magneto area that an fire the engine in reverse with I do believe that all the engines have the mounting tabs for but some need to be tapped. but... then you would have to add the wiring, mpem, RER secordary clutch, And pick up in the magneto, upgrade for sure but kinda a pain in the arssssss. but if you want time put a little time in, up to you, I do have a MPEM for both the 02 without RER and DPM and with bth as well if you need them
 

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RER means rotax electronic reverse. That's where the two trigger coils come into play. It momentarily stalls the engine, then fires it in reverse rotation. So you have reverse without having mechanical gears in the chain case doing it. Need a different secondary clutch though. To do the complete swap, you would need the appropriate MPEM, wiring harness, voltage regulator, RER button and secondary clutch. You would already have the needed flywheel, trigger coils and stator in the 700 motor I assume. One thing to note with the '02 Legend electrical system... They need a battery to run. No battery and it won't give spark to start. Another thing... A RER MPEM needs to see both trigger coils or it won't give spark.
 

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RER is Rotax Electronic Reverse. It allows the engine to run backwards, and the sled to move backwards. Thats what the second pickup coil is for. Im uncertain about not using the RER fucntion, but have used a DPM equipped MPEM without the DPM equipment plugged in..

You would need not only the 700 MPEM but the full 700 wiring harness, RER button& RER clutch for the sled as well.

The simplest method is to use the 600 MPEM, Stator & Flywheel and just the one pickup coil.
 

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Discussion Starter · #9 ·
Wow thanks guys, great information.

I guess the MPEM with RER would be the one i want because the plug on the end of the lead coming from the magneto on my 700 is square and it has to fit the MPEM. The 600 MPEM has the triangular plug.

Does the non RER MPEM have the square or triangular plug? From what i have seen i can't use the triangular plug MPEM with the 700 stator.
 

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The 2002 360w electrical system is much different than the 2000 290w. With the 360w, the stator feeds the voltage regulator then the voltage regulator feeds the MPEM. On the 290w system, the stator feeds directly to the MPEM.
On your 700 the stator doesn't plug into the MPEM, but the rectangle four wire plug for the trigger coils does.
This is a case where you are not going to be able to mix and match... You need to use one system or the other.
I agree with TT, easiest thing would be to swap the 600 flywheel, trigger coil and stator.
 

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And can you get the wiring from the 02 700... Would be the easiest way to do the swap, that way no splicing and its done right, or just transfer all your 600 electronics if they will fit (im not sure) to the 700 and get a reverse chaincase and make it easy if you want reverse.... so many options and 10 different ways to do it.
 

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Discussion Starter · #13 ·
Things do get messy when i try to modify things.

So if i get the wiring from a 2002 700, the MPEM and the voltage regulator i should be able to sort this out?

The engine will run ok with the DPM and RER disconnected? I can just leave the plug holes in the MPEM empty?

CrackerJack i am swapping engines because i got the 700 very cheap and it has very low hours on it. The most important thing is i am sick of the single ring pistons causing problems like ring de laminating and fast wear. I rebuilt the 700 with MCB dual ring pistons, love those ***** rings!
 

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Discussion Starter · #14 ·
If i was to go with the 600 stator and MPEM, which i think will physically fit ok, how will the 600 calibration, software and hardware work with the 700, anyone have any ideas?

I have checked some of the numbers from my 2001 manual and there seems to be 3 different hardware/software numbers for the 700 and 2 different calibration/software numbers. And the same for the 600 but none of the numbers match with the 700.

Can there be that much that is different between the 600 and 700 engines to warrant changing the ignition curves and timing. I don't want it to burn pistons and i sure don't want to kill the performance.

Any one know where i can get the MPEM programmer for these engines?
 

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I have torn a crap ton of these sleds apart and have never seen a 600 and a 700 have the same numbers or calibration on the mpem... but on the other hand I have seen 700 and 800 use the same number mpem so this leads me to believe the timing curves are the same on the 700 and 800 and different on the 600 and smaller bore sleds, but due mot quote me on that. I do have 4 mpems layin around 3 are for a 700 with and without rer and dpm if you need one let me know, don't have any use for them now since I have just revs now.
 

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Things do get messy when i try to modify things.

So if i get the wiring from a 2002 700, the MPEM and the voltage regulator i should be able to sort this out?

The engine will run ok with the DPM and RER disconnected? I can just leave the plug holes in the MPEM empty?

CrackerJack i am swapping engines because i got the 700 very cheap and it has very low hours on it. The most important thing is i am sick of the single ring pistons causing problems like ring de laminating and fast wear. I rebuilt the 700 with MCB dual ring pistons, love those ***** rings!
Yes you should have no problem if you get all of the 700 electrical system associated with the engine, but you will need the secondary clutch too if you want to use the reverse. The 700 will run fine on the 600 MPEM, done it a number of times, I even ran an 800HO on a 500ss timing curve for a season in a pinch and unless I told you, youd never know.

While Im not trying to make you paranoid, Im more concerned with the "Dual Ring" 700 pistons. Did you measure the piston to wall clearance on assembly? Reason I ask is that there's no such thing as a dual ring 700 piston, you were sold 670HO pistons and they're slightly larger than a real 700 piston. Id say as a guestimate, without having the bore properly sized, the success rate that Ive seen with the 670 piston in the 700 is around 50-60% if the bore doesnt have much wear and theyre tight, they're going to stick.

Ive built and owned many different variations of 700's and still have a ported 700 today in my 2009. Its my favorite engine and have found the OEM single ring Elko piston to be the very best for that application and I think youd be hard pressed to find a reputable engine builder that would dispute that. Most 700's will run 10k+ miles on OEM's and still crank 140 psi.
 

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Discussion Starter · #17 ·
Ok,now i am pissed off on two counts, no TT670 i didn't check piston to wall clearance, just ring end gap, silly of me but i just assumed the pistons would be right.

I just measured a set of 670 SPI pistons i have here and you are spot on TT, the pistons look identical but the 670 measures 77.9mm and the original Elko measures 77.8mm. To think i already had a brand new set of 670 pistons here and went and bought another set. To top that off i thought i was buying pistons made to fit the 700!

The bores were a bit rough so i had them honed with a diamond hone and i didn't notice anything out of the ordinary when i assembled the engine.

I think i am just trying to talk myself into trying the engine without stripping it to measure the piston to wall clearance.

I can't thank you enough TT, excellent information to have.

CrackerJack will your 700 non RER/DPM MPEM accept my 600 plugs from the magneto and ignition trigger or will i have to change the wiring anyway? I would need to get the DESS Cap key to suit the MPEM as well. How much do you want the MPEM and Key?

I really appreciate your input guys, thank you all for your help.
 

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While confirming the clearance always gives peace of mind, If you had them diamond honed odds are they could very well be just fine, especially when you take any bore wear over the last decade into consideration too. Just as an FYI for the future, to use 670 pistons in a 700, they must be 670HO pistons to match the combustion chamber as they are flat tops, the non HO 670 piston has a crown.
 

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sorry I Though bomber said Touring not Legend... wasn't trying to correct you bomber just semi retarded and don't read good some times.HAHA..... The legend does have the 360W magneto.
 
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