Snowmobile World banner

1 - 5 of 5 Posts

·
Registered
Joined
·
4 Posts
Discussion Starter #1
I have a freind that has a 2001 zr 440 and has gone through 2 sets of pistons within 200 miles. i have ben told they are melting down. He suspects the the power valves are not opening ,but we are not sure whats happening here. any help is greatly appriciated.
 

·
Registered
Joined
·
11 Posts
I have a freind that has a 2001 zr 440 and has gone through 2 sets of pistons within 200 miles. i have ben told they are melting down. He suspects the the power valves are not opening ,but we are not sure whats happening here. any help is greatly appriciated.[/b]


Engine is running too lean caused by improper jetting or possible air leak somewhere
 

·
Registered
Joined
·
49 Posts
I have a freind that has a 2001 zr 440 and has gone through 2 sets of pistons within 200 miles. i have ben told they are melting down. He suspects the the power valves are not opening ,but we are not sure whats happening here. any help is greatly appriciated.[/b]


the leaning out my be caused by a hot burning plug i think in the zr 440 u should be runing a "br9es" if i remenber right. All so if you take it for a good ride and get it nice and worm your plugs should not be lighter then a "double double coffe" anyways hope this helps
 

·
Registered
Joined
·
79 Posts
I've come accross a couple of instances where engines burnt-down & were warrantied by the dealer (twice), to later find out that there was a crack in the fuel supply hose INSIDE the fuel tank. I pull mine out once a year to check them. Hold it up to a light, and if you see any lines, which would indicate cracking, replace it. check with the dealer, because that fuel line is not always the same as what's outside the tank.
 

·
Registered
Joined
·
18 Posts
I would definately go up 2 on the mains put timing at -2.Start there you cant ride a 440 if your not
willing to get your hands dirty getting the motor dialed.Do plugs reads and pull the heads to read piston wash.Pulling the heads will only take about 10 min if that.Uncork the hose from the bottom of the coolant bottle first though.
I will tell you i had an 01 zr440snopro cross country edition that ran the best on 310 mains and -2 on timing.
I now have an 2001 zr440snopro snocross edition withe wiseco pistons and v force reeds and that sled has 270 mains and +3 on timing with pump gas premium.Dont know how to explain that but piston wash is perfect and you can hold it to the bar all day.
Always start rich and on the - side on the timing!
 
1 - 5 of 5 Posts
Top