# 3 sec of spark....



## Brute_Brian (Jun 10, 2011)

Going thru the typical "my brute wont run" diagnostics....
The front plug fires just fine as long as I hold the start button. 
The rear plug only fires for 3 seconds when I hold the start button.
I've triple grounded the frame / motor / harness so its not a ground problem.
Replaced both coils / wires / boots / plugs (and re-tried the old ones).
I'm thinking the Dynatek CDI is gone (even tho they "dont fail")
Any other ideas? 
Anyone locals have any stock CDI's lying around?
Im stumped.


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## NMKawierider (Apr 11, 2009)

Brute_Brian said:


> Going thru the typical "my brute wont run" diagnostics....
> The front plug fires just fine as long as I hold the start button.
> The rear plug only fires for 3 seconds when I hold the start button.
> I've triple grounded the frame / motor / harness so its not a ground problem.
> ...


Coil might be opening-up. Switch and see if the problem follows the coils.


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## phreebsd (Dec 16, 2004)

he said he replaced both coils. i think that dynatek is causing some beef.


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## speedman (Nov 3, 2010)

dynatek should be good, before it was on that bike we put it on another brute and it did good, but you never know pc3 i had didnt work left it in the sun for 2 days and started working again. check the fuses under the seat also, my fuses would'nt let the bike turn on at ryc last time.


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## Brute_Brian (Jun 10, 2011)

I re-did all the wiring and fuses when I first got the bike and swapped plastics (has ran perfect ever since). But I DID re-check and those are all good.
The symptom is really weird - front plug fires fine, rear plug fires briefly. I swapped the coil circuits front to back and the problem definitely follows the rear coil output wire (blu/wht) from the Dynatek. 
I just need a stock CDI to get it going.


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## primetime1267 (Aug 31, 2009)

Brian, I will get a hold of Matt and see if we can meet somewhere to try his stock CDI once again.


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## speedman (Nov 3, 2010)

then has to be dynatek, wish i had the stock one to send you but when i had the bike i traded it for the dynatek lol


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## Brute_Brian (Jun 10, 2011)

I really think the Dynatek has a bad rear coil output circuit - like a blown trace on the circuit board or something.......prob from all the ground wires I added to the harness / frame / motor :aargh4:


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## DAVIDSON (Oct 1, 2009)

This is strange.. I have a 09 brute 650i that will fire both plugs for about 3-5 seconds.. EVERY now and then you can get it to start but it acts like it is in kinda in limp mode although it is not. And it seems to have a low rev limiter around 2k or so.. It has already gotten a NEW pulser/crank trigger. Tried known good cdi box, swapped kebc modules etc.. This bike is pristine with no typical mud bike related corrosion that can be seen.. It looks like a nearly new bike. I have not checked the buss connectors due to how clean the bike is and it is hard for me to believe it could be there. Thinking about trying a good invert /rollover sensor.. What is really strange is this bike belongs to a friend. It was running perfect pulled into a garage and would not start the next day or start and run horrible. This is where i ended up with it...


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## DAVIDSON (Oct 1, 2009)

What i guess i should have asked is did you ever figure out what was wrong with this bike?


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## NMKawierider (Apr 11, 2009)

DAVIDSON said:


> This is strange.. I have a 09 brute 650i that will fire both plugs for about 3-5 seconds.. EVERY now and then you can get it to start but it acts like it is in kinda in limp mode although it is not. And it seems to have a low rev limiter around 2k or so.. It has already gotten a NEW pulser/crank trigger. Tried known good cdi box, swapped kebc modules etc.. This bike is pristine with no typical mud bike related corrosion that can be seen.. It looks like a nearly new bike. I have not checked the buss connectors due to how clean the bike is and it is hard for me to believe it could be there. Thinking about trying a good invert /rollover sensor.. What is really strange is this bike belongs to a friend. It was running perfect pulled into a garage and would not start the next day or start and run horrible. This is where i ended up with it...


Crankshaft position sensor. Either a bad connection or its failed.


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## DAVIDSON (Oct 1, 2009)

NMK,

It already has a brand new crank sensor . Just installed.. Same exact thing


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## NMKawierider (Apr 11, 2009)

DAVIDSON said:


> NMK,
> 
> It already has a brand new crank sensor . Just installed.. Same exact thing


Darn...looking more like the CDI then. Can you borrow one from someone to see?


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## DAVIDSON (Oct 1, 2009)

Nmk, Thats the thing i have substituted a known good cdi box, ebc controller, new crank sensor.. even substituted a tilt sensor same thing!!! And the diagnostics out of the service manual are almost useless. First brute i have had that gave me a fit like this.. lol Correct me if i 'm wrong on these bikes the stator has NO effect on the ignition system.?


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## NMKawierider (Apr 11, 2009)

DAVIDSON said:


> Nmk, Thats the thing i have substituted a known good cdi box, ebc controller, new crank sensor.. even substituted a tilt sensor same thing!!! And the diagnostics out of the service manual are almost useless. First brute i have had that gave me a fit like this.. lol Correct me if i 'm wrong on these bikes the stator has NO effect on the ignition system.?


The stator itself no, but the position sensor is in there...somewhere.. Might check the connectors.clean all the dielectric grease off everything with some sprat contact cleaner and try it. Sometimes the wrong stoff on the low voltage connection has a bad effect. Sometimes the female parts of the round connectors get spread apart with it and they loose contact..


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## DAVIDSON (Oct 1, 2009)

Just a update.. For reference the stator plays NO PART in firing the ignition system.. Only charging system.. It will run fine without it.. On this particular bike i found voltage was dropping very low on the cdi voltage supply wire.. Upon further inspection the "rest of the story" was this guys son had tried to tie into the ignition switch for a stereo connection and there was only about 3 strands of the entire 12 v feed feeding power to everything due to a botched connection. Repaired that connection and she runs fine.. I should have never broke my rule of checking everything and NOT taking what the owner said as gospel on what had actually happened.. Either way its fixed now..


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## tristin (Feb 6, 2013)

Brute_Brian said:


> I really think the Dynatek has a bad rear coil output circuit - like a blown trace on the circuit board or something.......prob from all the ground wires I added to the harness / frame / motor :aargh4:


was it your cdi I have the same problem?


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## brutepower95 (Oct 22, 2012)

i have a moose cdi and dynojet jet kit id sell


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