Tuning new carb...surging idle...stumble off idle

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ccpeters04

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I'm new to the forum and hope someone can help me out. I have a 2000 Warrior that I picked up a couple of years ago. It has been running, OK at best, but I decided to try and get it running right. The original carb had a stuck accelerator pump, and it actually messed up the plastic arm that actuates it. That was the first issue, can't stab the throttle from idle or it dies, but I could deal with that. Seemed to be running just a bit rich at idle since I got it. A couple of months ago I decided to get a new carb (NICHE brand knock-off from Amazon). Since I put it on, I can't get it to run well at all. The off idle falling on its face is still there. I am at 4500ft elevation, so I am guessing I may need a bit smaller pilot jet, but I want to get a second opinion. It also seems to hunt a lot at idle. I have played with the fuel screw, idle speed, main jet, main needle clip position, float height. I have clean non-ethanol fuel in the tank. Throttle cable is adjusted correctly. Any advice would be appreciated. I've never had this much trouble tuning.
 
Hunting at idle is usually valve timing or air leak. I'd start with the easiest by spraying carb cleaner around the boot between carb and cylinder while it's idling. If rpm changes, you have an air leak. Warriors are notorious for cracking intakes. Good luck
 
Hunting at idle is usually valve timing or air leak. I'd start with the easiest by spraying carb cleaner around the boot between carb and cylinder while it's idling. If rpm changes, you have an air leak. Warriors are notorious for cracking intakes. Good luck

Original intake manifold/boot was split. New one installed with the new carb. Tried the spray, with ether. No intake leaks.

I reinstalled the OEM carb and it idled smooth as butter for 20 minutes. It has the faulty accelerator pump issue, but the engine runs fine.

At this point I think I'm just going to get a rebuild kit for the original carb and repair the accelerator pump lever.
 
Tried that as well. The main jet needle looks slightly different (oem is shorter). The pilot jet on the new one has no markings on it for size. Neither do the extra main jets. The one that was installed had a 1.45 stamped on it, and that's the stock size. I'm pretty sure the pilot is just oversized and that's causing the problems.
 
I'm new to the forum and hope someone can help me out. I have a 2000 Warrior that I picked up a couple of years ago. It has been running, OK at best, but I decided to try and get it running right. The original carb had a stuck accelerator pump, and it actually messed up the plastic arm that actuates it. That was the first issue, can't stab the throttle from idle or it dies, but I could deal with that. Seemed to be running just a bit rich at idle since I got it. A couple of months ago I decided to get a new carb (NICHE brand knock-off from Amazon). Since I put it on, I can't get it to run well at all. The off idle falling on its face is still there. I am at 4500ft elevation, so I am guessing I may need a bit smaller pilot jet, but I want to get a second opinion. It also seems to hunt a lot at idle. I have played with the fuel screw, idle speed, main jet, main needle clip position, float height. I have clean non-ethanol fuel in the tank. Throttle cable is adjusted correctly. Any advice would be appreciated. I've never had this much trouble tuning.
Intake boot. Possibly.or your safety switch for the Ebreak.mine did same thing I replaced the boot and bypass the Ebreak safety switch.it ran great.I ordered New carb of Amazon and now it is smoking revving high and keeps dieing when given throttle.put old one back on and same thing.
 
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