Still fouling plug, help people...

[RiPPiNiTuP7]

A few weeks ago I posted on here how my 400ex kept fouling plugs...well most people said to lean the jetting. Well I tested just about every jet and all my quad does is foul the plugs. I think Iwent through about 10 or so by now. In the summer I used a 165 main, and a 52 pilot. Now I am at a 142 Main, and a 42 pilot and it still fouls the plugs. I do not get it. Is there something else besides jetting that will cause plugs to go bad? Maybe bad gas or something? Someone please help, this quad is 5 months old and I have hardly any riding time on it and its getting me very frustrated :(

BTW, the pic attatched is from a 142 main/42 pilot. All I have is an LRD Exhaust, K&N Filter, and the lid is removed.

[Doibugu2]

I am not going to be a big help here, but your way lean at 142.

My bike is stock other than the filter, and I am running 142. Try putting the lid back on, just for the time being.

Also, have you messed with the air mixture. I think its supposed to be between 2-1/2 and 3 turns. It seems like that is the only thing you haven't mentioned. Try checking that.

[jerry-89-250R]

i agree with trying it with the lid on, and you are lean,

[RiPPiNiTuP7]

OK, I'm still using a 152 main, and 42 pilot, but this time I stuck my lid on and here is the result with a new plug :(

[RED121572]

Running lean? Not with that black of a plug! If you were lean, your plug would look like xmas. Your plug wet by any chance?(oil)

You maybe running lean on one circuit and running way rich on another. I agree, check the screw.

[Doibugu2]

When is it turning black?

Will it idle fine?

We need to isolate it to where it is happening.

idle,1/4 throttle, 1/2, etc, like red said. We just need to start eliminate problems.

Sorry, man, but I feel your pain.

[RiPPiNiTuP7]

Ok, the plug is not really wet, it has more of a chalky type look to it. It will hold an ide...not totally smooth, but it will stay running. Every single plug I stick in it will turn black within 5 minutes of the motor running :eek:

Is anyone familar with octane boosters? Would this be of any cause to the bad plugs? I recently used a little bit in my motor because I couldn't get ahold of the correct octane, so I mixed some 87 octane gas...just trying to think of ANYTHING that would cause the plugs to go bad.

About the air screw, how many turns out should I go with it?

[jerry-89-250R]

your first post said 142 main that would be lean, now you said still running 152? are you riding it and doing a plug check the correct way? you can't do a plug reading idiling

[RiPPiNiTuP7]

Originally posted by jerry-89-250R
your first post said 142 main that would be lean, now you said still running 152? are you riding it and doing a plug check the correct way? you can't do a plug reading idiling

Ahh, sorry about that, I tried to edit my post and the page won;t load up for me, anyhow I had a 152 main in for both readings, the first pic is with lid off, the second is with lid on. I have not did plug checks the correct way, those are from running it in the garage, but the fact still remains...the plugs are fouling out...they shouldn't be doing that...

[Ralph]

the first thing you should do is check the gapping of th eplug a stcok 400ex plug should be at .6-.7mm (.024 - .028 in.)

you plug looks carbon fouled, are the plugs misfiering?
it is probably cause by spark plug heat range too cold, a faulty ignition control module, prolonged idleing, or bad compression. i would not think its from faulty cmpression cause ur machine in quite new, and i doubt it is your ignition control module for the same reason but it could still be the problem caused my loose wires and bad conncetions. another thing i would check is make sure u have a clean airfilter...

u welcome,
ralph;)

[odie]

IM reading in my ex repair book it says it could be from-

1.poor compression
2.clogged air filter
3.prolonged idling
4.faulty ignition control module-like mine was,I had a wb rex box
5.plug heat range too cold
6.rich fuel mixture

[powerslider]

You are definitely rich, are you running the stock plug? Try removing the air filter for a short time and see if it improves.
Check the float level, if it's to high it will run rich.
Where is the needle clip set at? Check the slide operation, make sure it closes ok. Set your fuel screw at 1 1/2 turns out with the 42 pilot, check all the vent lines, make sure none are plugged up.

If you have a propane torch you can clean the fouled plugs, heat them until the carbon is burnt off....

[Ralph]

im thinking ur wrong on the 52pilot

[Dave400ex]

Have you called LRD and told them what setup your running? They will know what Jetting to run any better then us, or at least be a good start...

[powerslider]

It shouldn't foul the plugs like that with a 42 pilot and a 152 main. I'm running a 42 pilot and a 150 main on a stock EX, lid on. No plug problem at all. Don't go any larger than the 42 on the pilot though, a 52 would be way to large for what you have.

[Ralph]

lrd told him 52:rolleyes:

[RiPPiNiTuP7]

I already called LRD before and they said a 165 main and a 52 pilot...I already know theres no way it will run like that. I'm not sure what else to do. I might break down and take it to the local shop (not a rip off dealer), and just tell them "fix it" :D

[Dave400ex]

lol a 52 pilot? Man that is huge. Maybe trying asking Jeff or Colby...

[powerslider]

Are you getting this info? Don't wimp out here, it's not that tough. Read the previous posts then do it. We are here to help!!!

That jetting info you got from LRD is for a 38mm Keihin airstryker for a 2 stroke motor, I have one.....

[RiPPiNiTuP7]

Originally posted by powerslider
You are definitely rich, are you running the stock plug? Try removing the air filter for a short time and see if it improves.
Check the float level, if it's to high it will run rich.
Where is the needle clip set at? Check the slide operation, make sure it closes ok. Set your fuel screw at 1 1/2 turns out with the 42 pilot, check all the vent lines, make sure none are plugged up.

If you have a propane torch you can clean the fouled plugs, heat them until the carbon is burnt off....

Ok to clarify a few of your questions, I am running the stock plug. My float is ok from what I can tell. The needle is in the 4th groove from the top as LRD said to do. The slide checked out ok. My screw is already 1 1/2 turns out as LRD said to do as well. I will go check to see if vent lines, etc are ok ;)

[jerry-89-250R]

a 52 pilot would foul a plug, where's your needle clip "position", are the boots tight, is the carb level "in the notch on the boot"?

[powerslider]

Drop your needle back to the 3rd position, you will be fine by tomorrow....

[RiPPiNiTuP7]

Originally posted by jerry-89-250R
a 52 pilot would foul a plug, where's your needle clip "position", are the boots tight, is the carb level "in the notch on the boot"?

Needle is 4th notch from top, and the carb is installed like it should be, I'm sure of that.

[jerry-89-250R]

i agree 2nd or 3rd notch from top down you should be ok 152 main 42 pilot,

[RiPPiNiTuP7]

Originally posted by powerslider
Drop your needle back to the 3rd position, you will be fine by tomorrow....

I will switch it back to the 3rd, but I can't tonight, its getting to late. Also, someone mentioned the CDI, err "ignition contol module"...I have a buddy with a spare one, I will also see if that does anything. I will update this post when I try these things out. Any other suggestions are more than welcome :D

[400exBro]

i am running a 160 main and 3rd notch on the needle with a 42 pilot and seems to run okay and it won t idle tho???

i also have 4 7/8 inch holes in my airbox... and i am only running a wb slip on...

no i am sure that the 165 is perfect (or some where in the region) for the lrd exhuast..

i would suggust you talk to lou(quad 041) and see what kind of jetting he was running on his ex with the lrd..

good luck, i know jetting is a *****

[powerslider]

I wouldn't worry about the cdi, from the info here you were just set up way to rich for what you have.

Do you know how to check the float level? If you have to take the bowl off this should be checked. I will tell you how and what it should be set at if you want to know......

[nakomis0]

Ok, man...

You plug is black as h@ll, moving the needle and whatnot is ok for finer tuning but basically just mess with your main jet.

The pilot jet, sounds slightly to big to me, drop that a few sizes. Its basically just for idle.. And if the bike is running good but just fouling plugs , then its the pilot.

You mentioned gas additives.. If you want to jet it the easest way, start with the basics. Fresh Gas, no additives. Hows your air filter? If its not clean, makes sure it is. Don't drowned it in oil, and give it a few hours to dry before you go out and try and jet your bike again.

How are you reading the plug? Are you actually riding the bike? If its just sitting there, your probably have that pilot to fat, and thats why no matter what you do its black. If you can ride it down the road thats better.

I would put a 148 main in, ride it down the road for a little bit, see how it feels. Look for top end bog, or backfiring. And pay attention to where it has hesitation and where it doesn't.

After you ride it down the road don't stop or anything, Shut the bike off while your going decently fast. And coast back. I think its called a 'plug chop' or something.

But anyways read your plug and go from there. If its black drop the main again, if its white go up a main.

I have done alot of jetting, and its a HUGE pain in the butt. But after you do it a bunch of times you can tell what to do just by riding the bike. Good luck, take care of the basics and you can do it.

Just be concerned with how it runs at full throttle. Get that first and get the midrange, and idle later.

[RiPPiNiTuP7]

Thanks for the tips guys, I will give them a shot and see how it acts tomarrow...I'm done messing with it for today :o

[beerock]

I dont think you have a jetting problem.

If it was your jetting and you didnt change anything from the summer it woudl be running more lean then rich.
(colder air needs a larger main)

Is it smoking at all?

U possibly have a bad cdi, bad ground, valve seal or the oil ring on the piston is letting oil by.



I would try your friends cdi and see if it fixes it.

[RiPPiNiTuP7]

Originally posted by beerock
I dont think you have a jetting problem.

If it was your jetting and you didnt change anything from the summer it woudl be running more lean then rich.
(colder air needs a larger main)

Is it smoking at all?

U possibly have a bad cdi, bad ground, valve seal or the oil ring on the piston is letting oil by.



I would try your friends cdi and see if it fixes it.

No smoke really..just for a couple seconds due to cold weather, etc... I am going to try a different CDI just to rule it out. I will see what happens, and let you guys know. Thanks for the help.

[Doibugu2]

Did you get it running?

There is some good info here, not from me, but hey.

[RiPPiNiTuP7]

I changed the needle position to the 3rd from top, and put some fresh stuff in...I was able to fire it up in my garage and let it run about 15 minutes and the plug didn't go bad :) I am waiting for my hubs to come in the mail, and when they do I will be able to take it out and see how it does. I have a good feeling it will be ok, but if something happens I will post back here to try to get the problem resolved. Wish me luck :p

[YZROOSTINYA]

a 165 is way too rich along with the 52 main

i am at 4th clip down on needle
158 main
stock plug heat range
42 pilot with my mods

i was fouling out with a 162,165,170 main

i am suggesting a 42
3rd clip
stock plug
150 main

[Leo]

before you go crazy playing with the jetting you have to RIDE the thing..

I could go out, start the quad cold, goose it a couple times and give you a plug that looks like that in about 5 minutes..

Just sitting there running the accelerator pump is dumping way more fuel than the motor needs during a no-load condition..

If I don't let mine fully warm up before riding it'll foul the plug every time.

Leo

Leo is 100% correct..trying to jet a cold motor is like pissin in the wind..:ermm:

[sly400ex]

Rippin, what's the outcome? Hope you didn't stay out in the garage with it running and the door closed!!!!:eek: :eek:

[Ralph]

i dont think he has gotten his hubs back yet,,,

[RiPPiNiTuP7]

Yea, I'm waiting for my hubs...I expect them anyday now. When I get them on I will take it out and see what happens :p

[RiPPiNiTuP7]

FIXED! :D I just got my hubs back from Pappy and I took it out for a spin and its running great. I guess all those times I let it idle in the garage got to it or something. Well at least its back in action now. Thanks for all the help guys.

[powerslider]

Good deal, what is your jetting now, pilot, needle setting, main jet?