how do i tell if my servo motor is working? and if its not was would this hurt?
servo motor
- Thread starter kbest.1990
- Start date
Remove cover. Upon start up it should cycle once. If it cycles a few times u got issues... if servo motor isn't working will cause engine failure
If it is a EFI you have to rev it up past 6500-7000 rpm to get it to cycle. Not sure on the carbed sleds.
Efi cycles once upon start up also
it doesnt cycle at all? could this cause the motor to blow?
My ECU is a 05 and it does not cycle on start up the carbs do tho.
Could be the motor but morso the ecu could be toast. You can crank the motor to open the valves and then start it up and rev it up past 7000 and see if it closes if not either ecu or motor.
Sorry that's interesting.
If your sled starts and runs and guages work it shouldn't be your ecu, just the servo motor. Replace that first or get a p.v delete kit of possible. The ecu is expensive. I'm no expert by any means but have had both ecu's and servo motors go out and in my case with the servo motor it was either the servo or electrical short. When my ecu's went out nothing worked
They don't. If I had a little more time I would look it up in the service manual and copy paste it for you. Only the carb models cycle on start up. the EFI doesnt cycle until 7000 rpm.
Had 1 ecu that i sold that had the servo circiut in it did not work which did not matter to the guy because he had STM valves in it. Spent a lot of time trouble shooting that one and yes the new ecu is almost worth as much as the sled.
The newer ones don't cycle either at startup.
I believe we're just talking 1Ms, which for most people means a 900. The carbed once cycle once on startup if they are working properly, 3 times if there is a problem. EFI only cycle at ~6900.
As backcountry said, newer (EFI for the most part) sleds also do not cycle at startup.
As backcountry said, newer (EFI for the most part) sleds also do not cycle at startup.
ill see if it cycles at 6900 rpm. if it is not working could it blow the motor?
D
diggerdown
Well-known member
It can't hurt the engine, it just runs bad. Usually if the servo motor is bad it messes the running up even at low rpm but like most electrical issues they can act up in several different ways. You can unplug it and pulg a voltage tester into the feed lines and check for ecu signal if that is a concern. If you can, borrow one from a buddy and plug it in for a try. The valves just open up the opening for exhaust to allow for more of it to escape. All the engines went to this to give a flatter power band. Big opening means poor performance at low rpm, small opening means poor performance at high rpm, hence the variable opening size. Being electrical, cats valves can give more problems that the pressure operated ones and electical feedbacks seem to interfer with good running engines!
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ok thanks for all the advice everyone!!
Didn't see what you are riding. Can tell you with my '05 M7 the real problem with the servo motor failing was that the ECU/engine kept going into limp mode when it noticed the servo had failed. Make's riding miserable. Keep's you from harming the engine but sure take's the fun out of a ride.
Will cycle once upon startup. If cycles 3x cables out of adjustment...
