CGC419
New member
- Joined
- Mar 1, 2004
- Messages
- 7
I have been doing lots of reading on jetting, and have a few questions to make sure I'm starting out right. My problem is on my 2000 Mountain Max one piston is running cold. It is the PTO(cluctch) piston and its EGT temp is 1/2 of what the other two run at. When first started, it doesnt seem to fire in the PTO cylinder- The plug is gassy/oily. It fires up when on the throttle, and seems to run well in the upper rpms, but hesitates off the start.All the way thru the throttle the PTO runs much colder, and touching the head confirms this.... So My questions are--
1. Does the PTO usually run colder? Would leaning down help this cylinder?
2. From Reading, I come to assume that higher elevations result in less air, so it will make my sled run richer, and lower elevations will have more air= would make it run leaner? Am I correct here?????
3.Weather Temperature affects the sled in that Higher temps=richer mixture, and Lower temps result in Leaner mixture? Is this correct??
4.Any Ideas why the PTO would run so cold on my EGT gauges.
(The center and mag cylinders seem to run perfect-- both at 800 to 1150 degrees)
Specs-- Sled has PEAK HEAD, PI TRIPLE PIPES, 800CC WISECO PISTONS,dial-a-jets, and larger than stock Keihn Carbs... I run at 4-7k elevation also.
This is a new sled to me and I need some help. Thanks all
1. Does the PTO usually run colder? Would leaning down help this cylinder?
2. From Reading, I come to assume that higher elevations result in less air, so it will make my sled run richer, and lower elevations will have more air= would make it run leaner? Am I correct here?????
3.Weather Temperature affects the sled in that Higher temps=richer mixture, and Lower temps result in Leaner mixture? Is this correct??
4.Any Ideas why the PTO would run so cold on my EGT gauges.
(The center and mag cylinders seem to run perfect-- both at 800 to 1150 degrees)
Specs-- Sled has PEAK HEAD, PI TRIPLE PIPES, 800CC WISECO PISTONS,dial-a-jets, and larger than stock Keihn Carbs... I run at 4-7k elevation also.
This is a new sled to me and I need some help. Thanks all
Junior
New member
the temp of the guage will depend on where in the pipe the EGT probe is.
As far as elevation goes, you're correct, running the same jet at a higher elevation will make it rich, at a low elevation will make it lean.
I'm not sure your problem is fuel tho, sounds more like a spark problem to me, being a size or 2 fat wont make it not run on that cylinder, it'll run like shit on that cylinder, but it'll still spit and sputter, enough to keep the plug dry. Sounds more like either the plug is just fouled or you're got a bad coil/wire. If I where you I'd check the resistance on the coil.
As far as elevation goes, you're correct, running the same jet at a higher elevation will make it rich, at a low elevation will make it lean.
I'm not sure your problem is fuel tho, sounds more like a spark problem to me, being a size or 2 fat wont make it not run on that cylinder, it'll run like shit on that cylinder, but it'll still spit and sputter, enough to keep the plug dry. Sounds more like either the plug is just fouled or you're got a bad coil/wire. If I where you I'd check the resistance on the coil.
I see you mention it has differnt carbs on it, are they rack style carbs or singles????have you ever checked the choke plunger on it? is it seating all the way? does the choke cable have slack in it? this will do exactly as you describe and is often over looked.
follow Dons advice, he knows his stuff. I just ran my viper with the new egt gauge on it. My pto egt sensor is about 1/2 inch farther away than the other 2 from the piston skirt, and it runs about 30 degrees cooler. However by doind a plug and piston check it is right on. My point is don't jet by the egt alone, there are alot of variables. Maxdlx
Junior
New member
Jet each cylinder individually, the old fashioned way, and set your alarm temperatures accordingly, most guages that have an alarm feature will alow you to set the alarm temperatures individually for each cylinder.
If you're running single carbs also make sure that your'e throttle slides are syncronized.
If you're running single carbs also make sure that your'e throttle slides are syncronized.
CGC419
New member
- Joined
- Mar 1, 2004
- Messages
- 7
Thanks for the advice guys. I will have to check the coil and see if it reads low...Will also check the choke cable. Another strange thing on that PTO cylinder is even when it heats up to 5-600 degrees after a good run, once i shut it off it instantly goes cold(like 100 degrees) while the other 2 cylinders gradually cool down...
Will try to get some pics of the plugs on here.
THanks, CGC
Will try to get some pics of the plugs on here.
THanks, CGC
