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hey guys quick fuel screw question...
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Posted by: idro

Ok, got the dynojet tool and was checking my pilot circuit. All seemed fine, i bottomed out the screw the engine died. Blah blah blah.

Ok my question is, on the fuel screw. I am really scared to start just backing the thing out a bunch, i really do not know how long it is. Can someone with a 05 or 06 400ex tell me how much it takes to actually back the whole screw out? I was doing the fuel screw adjust 'how to' on here and didnt want to go crazy with the screw right yet.

Any help is appreciated...

Posted by: MO-EX-RIDER

ive had mine 4 full turns out and it stayed threaded

Posted by: chiaml

out makes it run richer?

Posted by: GPracer2500

For a fuel screw, out is richer. Normal adjustment range is around 1 to 3 turns. Beyond three turns out and there's usually very little effect.

Posted by: kcliff

unless having a 90degree angle flat head screw driver or taking the carb off you cant get to the air/fuel screw right?

Posted by: idro

well, i did something. It's 20* outside and probably like 50 in my basement and i went downstairs and hit the start button 1 time with no choke and it crunk right up. Last it was running was about 4pm and its now 9pm now...

was very amazed.

FYI i havent taken the 38 pilot out atm, the pilot circuit check indicated i didnt have to replace my pilot jet. If i have time this weekend ill break it down and install it, but i doubt i need to.

Posted by: hornetgod13

I have the same DynoJet "D" shaped fuel screw tool. With a Sharpie marker I marked a RED line on one side of my tool and a BLACK line on the exact opposite side to track every half turn I make on the fuel screw. I backed mine out to between 2 and 2 and a half turns. Between 1 and 3 turns is typically normally if you have the right sized pilot jet installed.

Posted by: hornetgod13

quote:
Originally posted by kcliff
unless having a 90degree angle flat head screw driver or taking the carb off you cant get to the air/fuel screw right?

If you have a 2004 or older 400EX than the fuel screw has a flat tipped head. If you have a 2005 or newer than it's a "D" shaped screw which requires a special tool. I have learn from other that with the carb removed, you can remove the screw with needle nose pliers and cut a slot in it so you can use a screwdriver to adjust it.

Posted by: NRTHBUSH

can you post a pict of this tool? and were can i buy it? my 400 is runing way rich and im fouling spark plugs. even after i put a FMF power core slip on exhust on. no air filter kit yet just stock and no jeting done yet. but it will be done shortly....

Posted by: hornetgod13

The part number is DT008. It's made by DynoJet and come with there DynoJet kit for 400EXs. I imagine you can contact them by phone or e-mail and see if they will sell just the tool individually. You could also check with a Honda dealership but, I'm sure they will overcharge you for the same tool.

Posted by: NRTHBUSH

do most jet kits come with this tool?

Posted by: hornetgod13

I know the DynoJet kit does. I don't know about others.

Posted by: NRTHBUSH

seems like dynojet is a pretty popular jet kit for the 400..... did the kit come with a k&N air fillter or did u get that seperatly....

Posted by: hornetgod13

I have a UNI filter. The Jet Kit comes with a fuel screw, adjustable needle, main jet adapter, and 10 various sized main jets. I used the needle and fuel screw tools and ended up switching my main jet back to keihin. I prefer sticking with stock brand jets.

Posted by: NRTHBUSH

i was runing rich before i put on my FMF power core exhaust .. but other than that the jets and air filter are stock untill i can get it here they said 10 to 12 days.... and i can't adjust my air fuel mixtuer becuse of that special tool u need. i put in a brand new spark plug put about 2 hours of time on it pulled it and it was black. thats just not right. any suggestions on how to lean it out.... i thought for shure that the exhaust might do it while im wating for my jets and fillter..

Posted by: hornetgod13

It's fairly normal for the outside thread area of the plug to be black. It's the center of the plug that you should look at. The porcelin below the electrode should be a tan color or roughly the color of a brown paper bag if your jetting is correct.
What's your altitude? Is your filter clean? A great way to lean it out is pull your airbox lid but, you have to be cautious or mud and water when you run it that way.

Posted by: NRTHBUSH

nope its black to the point were the bike won't start.

my local shop doesn't sell the proper tool and they won't even look at my bike for 4 weeks... to busy with skidoos they don't think we can ride in the snow.
im at about 1500ft. does air temperature afffect your jeting too? around here in the winter it can be any were from 3*C to -50*C
the coldest we go riding is about -20 to 25*C.

Posted by: hornetgod13

Elevation and temperature have a lot to do with jetting. The higher the elevation or warm the air is the thinner the air becomes. Those at sea level can run a larger jets than those at 3,000 feet.
Are you certain someone hasn't jetted your quad already. Did you get it new?
If it's really that rich than it should work fine with the lid off until you get it rejetted.

Posted by: garandman

quote:
Originally posted by hornetgod13
If it's really that rich than it should work fine with the lid off until you get it rejetted.

If his jetting is so rich it won't start, taking the lid off certainly won't hurt, but to say it "should work fine" might be a tad wee little bit of a stretch.

Posted by: NRTHBUSH

yes i bought it brand new and havent re jetted. the only thing ive done to it since i bought it was play with the idel screw. and put a the FMF slip on pipe on. i ordered my jet kit and air filter today but it won't be here for 7 to 10 days. any one know of a way to turn the fuel screw with out that special tool?

Posted by: hornetgod13

You can remove the carb and spin the screw out with a small pair of needle nose.
I would just wait a week and adjust it when you have the tool or ride with the airbox lid off

Posted by: NRTHBUSH

good thing i have some extra spark plugs then..... the thing is gona eat them up and spit them out.

Posted by: hornetgod13

If you pull your airbox lid off it should be fine until you get it rejetted. You shouldn't have to go through spark plugs.

Posted by: NRTHBUSH

if the darned thing will even start ..... ive got spark... so im guessing it has somthing to do with my jetting to.... it only starts when it wants to lol.

Posted by: AbnMP13

I went to my dealership and the guy gave me a tool for the screw. They come with jet kits and evidently my dealer keeps them. I know him well so he gave it to me.

Posted by: NRTHBUSH

yea i went to my dealer were i bought quad and they said they have never heard of this special tool and that a flat head screw driver would work... i told the mecanic he was full of it bc i had my carb off to get a good look at the fuel screw and jeting. my jet kit is on order so hopfuly it comes with the tool i need..... just didn't realise that the pilot jets don't come in a jet kit... so i guess i need to order one..... right now its 38..... should i order a 42?

Posted by: hornetgod13

Either get a 40 or 42. Most get a 42 installed because it pretty much removes the nightmare of the cold winter starting that most 400EX owners have learned to dread. Buy your new pilot from www.jetsrus.com