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Discussion Starter · #1 ·
BackGround: 2007 MXZ Blizzard 800 H.O. PTek, 144 engine light flashes

Sled had lots of electrical problems and battery dying.,, eventually going dead... Gauges going whacky or not working, cluster lights blinking, headlight 1/2 bright, engine surging at idle....seemed to work ok when rpm high.... I replaced relay... works much better, gauges working, lights working, no surging, however battery continues to drain and when battery voltage gets low 10-11v..tach wont work at idol...sled continues to run

I ran the sled with multi-meter hardwired to battery.... When cold, battery responds to 13.5-14.5 v, approx 2amps across 30amp charging fuse. Once warm or high rpm... suddenly voltage drops to 12.? (what ever battery is at time) then battery voltage stays low, doesn't respond to rpms, and continues to drop over time...you can see a small voltage drop when turn on accessories or brights....
Once low less then 11 v or so tach starts to mess up at idol, however sled runs fine. I do find the battery lasts longer without headlights or accessories on

After driving a bit the sled can be difficult to start, reverse wont engage...then back fires while starting after a few minutes and then starts and reverse works... seems like its running rich and is a little flooded???? plugs show rich.

I have replaced: Relay, (improvements), faulty handwarmer and switch (no change), voltage regulator (No change), inspected wiring, locked out accessories, lights by pulling fuse... no real change, checked grounds, checked for a "draw", tested battery x2 both checked good, replaced all fuses (no change), repaired one small wire (on top of battery, 30 amp fuse to battery post) no change, tested for continuity in tail light and headlights, replaced spark plugs (no change)

Stator:

Continuity Test: to spec
Insulation Test: to spec
AC Output (engine cold): 0.8-3.1v (spec is 3.5-7v) Did the test several times highest reading 3.1
I cant start sled without battery and when I pull the 30amp fuse its stops running
My best guess: Stator or wiring from stator, ECM or faulty wire /connection etc. in some mystery location. However i am leaning towards stator.... My skills are ok.. but i am no pro so maybe my diagnostics arent correct etc

Any way I can rule out stator vs ECM..... any thoughts out there. I am stuck

G
 

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BINGO!!!
 

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When cold the battery is being charged, and when the sled is warm the battery is being asked to supply power the electrical.

You also saw the relationship between battery voltage and how well the sled starts and goes into reverse, and the funky needle syndrome. That is the difference with having a Volt Gauge hard wired to the sled.

Nice work!
 

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Now it's time to get the right tools to do the job right. No skimping here please.
 

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Almost forgot the Backfires!

Haha, that is another relationship with poor voltage.
 

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Discussion Starter · #6 ·
Judging by your response you are agreement that stator needs replacement? I am going to have a "pro" confirm my diagnostics...this pm. I have replaced stators in other sleds however they were "less" electrical... .

G
 

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Chances are good. You could ride until the battery charging circuit drops then leave it cool down for 30min or so to see if it gets back to normal.

When cold, battery is being charged between 13.5-14.5 Vdc with a 2A draw.

When warm or high rpm...suddenly voltage drops to 12.x and progressively drops from there.
 

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Discussion Starter · #8 ·
Hey Thanks

So i re checked the stator.... I had plugs in first time so i pulled them out...got up to 4.5v ac (cold) highest so seems ok (cold) need to test warm... I took it for a 10km ride... battery started at 12.96v ended at 11.91.. just ran light, little to no response to increase rpm. It was a little sluggish to re start after ride but much better... I find if i drive it with a little more jam it restarts better...I am having an expert take a look at it and recheck some of my diagnostics...

Updates to follow... suggestions welcome...

G
 

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Curous to see more info on this... particularly like checking stator and regulator

I have a 04 GSX 600 SDI that doesn't appear to be charging anymore... ran the battery dead on the trip back yesterday. Haven't had to do much to this sled, so it took a while just to find out where the regulator was located.

I went through all the fuses and relays. I was thinking the lights and grips were powered directly from the stator (maybe through a rectifier), but it looks like they are powered via the regulator. Seems like the 'run' relay when it's energized caused the battery voltage to 'backfeed' to the lights and heaters. I should have pulled those fuses and we probably could have made it back just on the battery, if I knew then what I know (or think I know) now. Is that right?

How hard is it to get the regulator out... if I remove the exhaust is it fairly simple or is there more that needs to come out??

Similar question on the stator (if it got that far)... do you need to pull the engine or can it be done with it in the sled?
 

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Discussion Starter · #10 ·
So all is fixed. Long story short it was the relay and the stator. I replaced the stator with engine in.... a little frustrating but got her done. All codes cleared non returned, no back firing.......... runs excellent.

Thanks for a ll the help

G
 

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Discussion Starter · #11 ·
The voltage regulator is relatively easy. Just pull the exhaust and muffler... 10 min. I also bought the manual start wiring harness for mine...in case battery ever goes... and as a diagnostic to rule out problems with electric start etc..

G
 

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So all is fixed. Long story short it was the relay and the stator. I replaced the stator with engine in.... a little frustrating but got her done. All codes cleared non returned, no back firing.......... runs excellent.

Thanks for a ll the help

G
Nice going! It must have been frustrating to work in a tight spot, but it beats the trouble of removing the engine. With good voltage you should no longer have trouble with the relay as long as the contacts are clean and with a little dielectric grease.
 

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Great idea to carry a manual start wiring harness for trail side maintenance. A good battery will help keep the stator happy. Since the stator is new this would be a great opportunity to take some voltage measurements at different rpm for a benchmark and posting the results. Take note of the ambient temp, number of days the sled has been resting and how long it ran prior to the test. For example the battery measured 12.6 Vdc after sitting 3 days at -20C (-4F). The battery after 2 min of warm-up idle at 1800 rpm was 13.9 Vdc and 14.2 Vdc at 3000 rpm. After a 1 hour ride it was 14.6 Vdc at idle and 14.4 Vdc at 3000 rpm.

Simple stuff like this can go a long way for future troubleshooting and help others along the way.
 

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Discussion Starter · #14 ·
Hey Thanks

I will take a few readings....heads up to all putting in new stator... remove coolant reservoir, loosen oil reservoir and remove or at least lift out way //carbs. Makes it much easier

G
 
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