Arctic Chat : Arctic Cat Forum banner
1 - 3 of 3 Posts

·
Registered
Joined
·
37 Posts
Discussion Starter · #1 · (Edited)
In the continuing story of my 2007 Artic Cat 500, which runs rich and rough at idle, I’m trying to figure out whether I have the stock jets in my carburetor. What I found inside my existing carb is a number 40 slow jet, a number 85 starter jet, and a number 142 main jet. As you can see from the service manual excerpt below, the number 142 main jet does not match the specification. The service manual says it is “138” but the parts manual doesn’t list 138 as an option, listing instead main jets ranging from 142 to 150. I’ve found quite a number of errors/inconsistencies in these manuals. Does anyone know for sure what is the correct main jet, and even better the OEM part number for same? Would an oversized main jet cause a rich idle condition?

Rectangle Font Parallel Screenshot Number
Font Parallel Number Rectangle Screenshot
 

·
Registered
Joined
·
37 Posts
Discussion Starter · #2 ·
Parenthetically, the main jet for a model 400 (CVK34 carb) is listed as a number 135, and the main jet for a model 650 (CVK36 carb) is listed as a number 132. I would think that the main jet number for the 650, having the same carburetor but a larger engine, would be larger than the main jet number for the 500, but the manual suggests otherwise.

Rectangle Font Parallel Number Screenshot
 

·
Administrator
Joined
·
7,990 Posts
If it has a dyno jet kit in it, the numbers wont match. This would come into play if you are not the original owner and dont know its history. Second a 142 main jet has absolutely nothing to do with idle and comes into play at half throttle and up. 3rd a 142 isnt that much larger than the 138. A starter jet and a slow jet can be put in the wrong spots, actually flip flopped as they are the same threads. On the exterior of the carb bowl is the pilot jet adjustment screw. If its more than 2.5 turns out, it may idle rough and rich. A dirty needle and seat may cause a rough idle. Carb machines are dinosaurs as everything is EFI now. Nothing wrong with carb machines though. Hows the air filter? if its falling apart, it will cause havoc to a carb. I would look at the electric choke first and see if its fully seated while its running, if not a rich condition would exist.
 
1 - 3 of 3 Posts
Top