Snowmobile Fanatics banner

1 - 6 of 6 Posts

·
Registered
Joined
·
12 Posts
Discussion Starter #1
Ok so here is the story. My buddy bought a 2004 pro x 440 with a 600 ves motor I believe It is from a 2000 xc from the extra parts that came with it all gen 2 stuff. He got it guy said it needed carb work or something never ran right motor made bad noises tore it apart replaced pistons and outer crank bearings now noises are gone but it won't run right like its stuck in limp mode can't get it to rev over 6000 rpm on stand off it is a turd barely moves. Replaced exhaust valves since it had 2 different ones on it, tested stator, Cdi, coil, temp sensor all ok. Timing is at 23 btdc with tps unplugged with plugged in its at like 12 checked with timing light. Runs the same whether tps is plugged in or not. Unhooked lighting circuit to check for draw no change in rpm. Clutching is my thought but they both appear to work as they should red epi primary 58 weights yellow secondary spring unsure of brand and helix. Im wondering if the absence of the key with the premium control is making a difference in it somehow. The Cdi is correct for the 600. I'm stumped and looking for any guidance any one who has done the swap before or who is just generally smarter about this than I am May have for me. Thanks in advance for any help.
 

·
Registered
Joined
·
3,435 Posts
have u checked the VES system to make sure the valves aren't gummed up?
 

·
Registered
Joined
·
2,708 Posts
I would be looking at the valves probably. Are the bellows sealing and allowing the valves to open, or are they warn out and need replacing. Also what are the exhaust valve springs like? Like XC600RMK said, are your sure that the valves are clean and not sticking to the cylinder.
 

·
Registered
Joined
·
12 Posts
Discussion Starter #4
Ves is clean bellows and springs are in good shape. Tried different ones no change.
 

·
Registered
Joined
·
3,435 Posts
sounds like clutching, madcow is great with clutching advice if u need any. Also are the clutches clean and working proper, if you raise the rear of the sled are they moving good and to top and bottom?
 

·
Registered
Joined
·
12 Posts
Discussion Starter #6
So here is an update on what I tried today. Ran with belt off I know bad Idea but I had to see I got it to 7500 but didn't want to push it anymore than that. Tried a different secondary with same result only 6k. Wondering if the primary is causing it all seems good they both open and close. Also had the wrong belt on it had a polaris 1175 I put an 1180 off my 03 pro x 800 on it didn't make a difference. Would it do any good to pull my clutches off my 800 and try it it is piped not sure how they are set up just got done building it and haven't dug into them yet. I would think if the clutching is the problem it would at least be better than it is now.
 
1 - 6 of 6 Posts
Top