Got new jets fired up still same issue

[dirtrider73068]

Well got my new jets in, run down had a 136 main, 42.5 pilot, I took carb apart when put back it will stall or fall on its face if you blip the throttle or punch to WOT. I put in a 45 pilot and a 150 no change, but If I cover the intake but leave about a 1/4-3/8 gap between my fingers it revs right up no problem, so its getting too much air and not enough fuel, I would have thought going up on the pilot a tad and more on the main it would have made a difference but nothing has changed. Any ideas, the main jets I got were a 145, 150 which is on there, 152.5 155, and a 157.5 I would think I would have to go up to the 157.5 to get any results.

 

[Gen1Pat]

I would continue increasing the main until it runs right. Obviously you need more fuel to compensate for air you're pulling in. You may not have to go as big as the 157.5, but until you do some trial and error you're not going to know for certain. Just to be sure, your intake boots and manifold are in good shape right? No extra air getting in there? If you put in that 157.5 and it revs up good but surges at wot then back down 1 size on the main until it runs without surging at wot.

 

[dirtrider73068]

Ok I thought about going with the 155 since its in the middle, I have the needle clip on the 3rd from bottom or 4th from top. I am sure its not the intake boot I have spray it with B12 and nothing changed. I thought about getting some RTV black and covering the boot real good just to seal it off to rule that out.

 

[Gen1Pat]

Factory needle clip position is right in the middle. So you've richend the mixture by moving it down. Have/what mods have you done to the air box and the exhaust?

 

[dirtrider73068]

No mods to the air box has a K&N air filter, a FMF megamax suppertrapp muffler with the disc removed. I have turned the mixture screw almost till falling out that didn't change anything.

 

[Gen1Pat]

Turning the screw out leans the mixture, in richens. Put it back to stock setting and see what happens. I have a dg O series slip on with a slightly modded air box lid and foam filter. I'm runing stock pilot and a 155 main. I would put that screw back to stock and readjust jets from there.

 

[dirtrider73068]

Oh ok thought out would richen it, I am trying the 155, one thing I am wondering is the fuel filter could it be getting plugged up for some reason, I have another fuel filter on the bowl vent I thought about swapping it out if it still does it, maybe it needs a fuel filter.

 

[dirtrider73068]

I put the 155 in there no dice same thing, turn the mixture screw all the way in no change, almost all the way out no change, gave up for now it was getting dark and I was needing food. Will try my biggest jet and go from there.

 

[geeessfore]

Turning the screw out richens the pilot not leans. If you have to unscrew more the 3 1/2 turns they recommend going one step up.

 

[dirtrider73068]

Think i got it going. I first took off the fuel filter thinking maybe its plugged up same thing no change so then took petcock off fuel tank and there was gunk on it cleaned it off swished tank around dumped some gas out through the holes put it back on. Had a fuel filter on the vent line so used as the fuel filter put some gas in tank.

Took carb back off put my largest jet in a 157.2 put all back on fired it up still same deal let run some turned air mixture out 3 turns and it got better, so took it out for run down the street and its doing fine! Turned the mixture screw back in till it cut it gassing it then back out a half turn. So think its all done I can't believe i had to put in a 157.2 main this thing must be geeting good air flow or something but its all good its a PIA to take this carb but I have gotten really good at now.

 

[Gen1Pat]

Turning the screw out richens the pilot not leans. If you have to unscrew more the 3 1/2 turns they recommend going one step up.

I'm glad you caught that, dude. I really need to start proof reading my ****!:argh: Sorry for the missinformation dirtrider. If we ever meet up on a trail you have my permission to throw roost in my face for being a *******.

 

[dirtrider73068]

lol its all good, I was wondering that when I read it but thought maybe with the wheeler it could be backwards or something.

But over all its alot better, I did let it sit for a bit and cool off after I was giving it test run. I went to start it and its kind hard to start have to give it gas before you didn't and it still stumbles but let it run and it won't gets better, so either need either one more step up on main or pilot, or look at adjusting the float maybe there is not enough fuel in the bowl, I am thinking about taking it back off hook it to the tank with the bowl off and lift the float up see where it shuts the fuel off. But don't think thats it, since once it gets running it doesn't do it, also though about needle jet going up a clip, its on the 4th from top or 3rd from bottom which ever way you look at it. But at least its better, and think the mixture screw is at 3 turns out. Might just get couple more bigger main jets another step up pilot jet if these little tweeks don't work. But most important thing is I need a battery.

 

[MotoArts]

Stumbles ONLY when you blip the throttle? Can you "sneak up" on the revs and will it run mid/high RPM?

Sounds like an accelerator pump circuit issue to me.
Have you verified that the nozzle is discharging properly? The circuit is very tiny. Might be plugged a little.

Just a thought.

 

[dirtrider73068]

yea when the blip it or just go WOT it will stumble but you can ease up all the way to WOT it won't do it, I know the accel pump is working, with it off you can work the throttle and a good stream comes out. If you ease up past idle you can goose it fine, slowly goose it, its fine, but just to blip it or pin it WOT it stumbles.

But once it runs some let it warm up it won't do it.

 

[Gen1Pat]

Glad you're okay with it, cause I'm not! I do this **** for a living, take pride in my work, and stand behind it. I kinda crapped in my own backyard, lol. But, I guess there is only so much info the human brain can retain/process after beating your head against the wall with problem vehicles, and customers, all day. Just for ***** and giggles, is the accel jet squirting towards the engine? I did have an issue on a older warrior where the jet's whole was worn out and the jet spun around backwards. But, you did say it goes away once warmed up, so that kinda eleminates that possibility. How long does it take for it to warm up and go away? It could just be because it's litterally cold. All 4 quads in my family need to warm up some before you can blip or wot them without stumble. After warm up no probs at any throttle, fast, slow, stop, go, hills, pulling a trailer, you name it.

 

[dirtrider73068]

It might be but with the old jet which was a think 139 or could be a 136 I could look but don't want to go out and look, you could pull the choke(most times wouldn't have to) hit the start and it fire right up, take choke off would have to hold throttle to let it idle some till got some warmth in it then would idle just fine but now with this bigger jet it has to have some gas to it to fire up, and in this whole proccess I could have full choke and it would idle and could pin it to WOT, take choke off no go. So I know it needed more fuel. I am going to try something tomorrow when I get a chance, I am going to fire it up with choke on little throttle see if it idles with choke on, let it run for a few get warmed up then pin or blip the throttle if it doesn't stumble then its going to have to warm up.

Before when this mess started it didn't matter if it was cold or warmed up or hot it would stumble when blipped or pinned. But what gets me just letting it sit for about 15 min I had to let it run for a few before I could blip the throttle even after it been started and ran when I was test riding it.

 

[MotoArts]

I have turned the mixture screw almost till falling out that didn't change anything.

This says pilot jet increase needed. Look at the carb. The pilot meters what is discharged past the screw's taper.

Still may have leaky intake issue too (?). Sounds like needle height would have little to do with this symptom, main jet even less.

Go fatter on the pilot till she gags at/off idle, then back up.

 

[dirtrider73068]

This says pilot jet increase needed. Look at the carb. The pilot meters what is discharged past the screw's taper.

Still may have leaky intake issue too (?). Sounds like needle height would have little to do with this symptom, main jet even less.

Go fatter on the pilot till she gags at/off idle, then back up.

Thats what I was thinking going up a step on the pilot have a 45 in there right now next step up on pilot is 47.5 I think. Don't think it has a intake leak but anything can happen, might have to get the spray out again and see, I do know when I started this mess, it would not take long after start up for it be hot, not warm but hot with in couple min of running, and it only about 60 outside, it didn't do this before.

 

[Rhyno]

Just hangin' out and watching/ listening......

-Rhyno