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Discussion Starter · #1 ·
Anyone know about the power valves/servo motor on the ZR440 SnoPro? It has the adjust timing box from -3 -2 -1 0 1 2 3 My question is... When i had the sled running with the hood open, I turned the dial to -3 and nothing happend... I then turned it to +3 and nothing happend... What is this exactly adjusting? I then had a friend lift up the back, and ran the track more then half throttle and seen the servo motor that controls the cables to the valve covers... But when i was riding, the sled would get very! doggy, bottom and.. top end... so i would stop, and manually turn the servo motor to make it pull the cables outward... Then it ran fine I guess. had good power...

Is that servo motor move throughout the throttle position as you get faster? or does is it suspose to go to only a set adjustment setting from -3 to +3?

Me soooooooo confused!

Ben
 

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you have to have the sled offf in order for the timing dial to work..i would leave it at 0 if i were you, this gives you more timing advance if you don;t know what your doing you could do some serious damage!!!.... the servo motor should open the valves as you give it gas, when you have full throttle it should open all the way.....take your power valves out and clean them, and check to make sure your servo motor is working properly...if you don't know how to do it have somebody who does, you should never have to manually open your power valves!!!!!!!
 

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Discussion Starter · #3 ·
Thankyou for posting. So as I give it more throttle, The power valves should gradually open? or does it open when you pass the 3/4 mark?

I founda manual for 2001 Arctic Cats, but has nothing to say about the power vavles... Can you run me a quick list on what to do?
 

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I had 01 AC ZR 600 efi w/power valves...at about 4000miles I decided to clean them myself. Actually not too difficult...just pay close attention to what you're doing as you disassemble. (I don't recommend drinking 4 beers while doing this job)
First, check your cables...THEY MUST move freely...no corrosion, no kinks, burned/melted, gummed up cables. Replace if needed. The Servo will not be able to "work" when cables don't move freely. Next, remove cables from servo...be sure to note which one goes where on the servo. Now remove PV covers...inside will likely look black and sticky...you're gonna clean that up. Now you have to remove the retaining collar...and the screws that hold it in place are usually very tight...WD 40 can help. continue to take note as how each piece comes off...now Slide PV out carefully...detach...Clean it with carb cleaner and soft towels...reassemble it...OH...replace the gasket...you likely ruined it when you removed cover. BE SURE PV goes back in the same way it came out...NOT up side down. NOW,,,do the other side...NOTE...if PV's are put in up side down engine will not perform well....
 

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Discussion Starter · #5 ·
Anyone know how long the exposed cable at the servo motor end is suspose to be? So I know how its opening far enough like is suspose to.. and not hard enough stressing the servo?
 

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No doubt or you can just replace them with the Supreem Tool and be done with them!
I lost a valve and piston at bout 800 miles!
 
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