carb problem

[Flyin#3-1/2]

i went outside today to start up my 400ex to check the oil, and the carb made a coughing/hitting noise. so i turned it off and looked at it. and i started it back up while looking at it and it runs for 1 or 2 seconds then the carb kicks violently once and makes this loud cough noise like it's hitting against something. can anyone tell me what could be wrong?? it's almost like it's backfiring through the carb:confused2

[Flyin#3-1/2]

could the intake boot be bad? it looked like the carb wasn't in it all the way, i haven't tried fixing it yet....and also could it be the spark plug? i put in a DPR8EA-9 instead of a DPR8Z.....so could that **** it up? (it's NGK) the store didn't have any of the 8Z's....

[Flyin#3-1/2]

someone PLEASE help me, i wanted to go riding SOOO bad today, and i don't want to put in a new spark plug and end up ruining it, so somebody please give me at least an idea of what might be wrong!

[JOEX]

First off put the right spark plug in. Some plugs have a longer threaded part some have a shorter one. If it is longer there is a chance of the piston hitting it. At least compare the two to see if they are the smae length.

Make sure the carb is hooked up properly.
Did you make any changes recently?

Joe

[Flyin#3-1/2]

no i haven't made any changes, and it was running real well the past two days. and i just picked it up three days ago. the guy said he hasn't done anything to it since last year, and he hasn't really ridden it since he brought it to Honda service to get checked up in 2002 except start it up and ride it around the yard with his son to keep it running. i'm going to change the plugs and see if it still does it.

[swamprider7]

My old warrior was doing the exact same thing. It turned out that it had a crack in the intake boot going from the carb to the motor and it was sucking air. I would bet that is the same thing that is happening with you. Make sure the carb is in the boot straight, and that the clamps are tight! Good luck.

[Flyin#3-1/2]

Originally posted by swamprider7
My old warrior was doing the exact same thing. It turned out that it had a crack in the intake boot going from the carb to the motor and it was sucking air. I would bet that is the same thing that is happening with you. Make sure the carb is in the boot straight, and that the clamps are tight! Good luck.

tomorrow i will drive it into my garage and take it apart, look at the boot and hope it's that because that won't be too hard to replace, it'd be better than having to replace a whole carb:ermm: .

thanks for the help everyone

[cals400ex]

the dpr9z is a colder plug which will make it harder to start and won't idle as good. check the intake boot also.

[swamprider7]

Originally posted by Flyin#3-1/2
tomorrow i will drive it into my garage and take it apart, look at the boot and hope it's that because that won't be too hard to replace, it'd be better than having to replace a whole carb:ermm: .

thanks for the help everyone


You might not have to replace anything. The carb just probably needs to be moved a little so it is sitting correctly in the boot. Don't forget to retighten your clamps!

[zlam27]

when i first start mine up, it likes to "chirp" and you can see the carb moving a little bit. it looks like a backfire through the carb kinda. i think its just a cold engine thing. my boots are on tight and im pretty sure there are no leaks. after its warmed up it quits doin it. i would make sure your plugs are the exact same lenght, then just run it a little bit to see if it stops once its warmed up.

zach

[Flyin#3-1/2]

Originally posted by zlam27
when i first start mine up, it likes to "chirp" and you can see the carb moving a little bit. it looks like a backfire through the carb kinda. i think its just a cold engine thing. my boots are on tight and im pretty sure there are no leaks. after its warmed up it quits doin it. i would make sure your plugs are the exact same lenght, then just run it a little bit to see if it stops once its warmed up.

zach

umm...this is the first time it's done it, and it's not a chirp, and if it is, then it's one big *** bird, lol, but it happened after it warmed up, and it's warm outside, probably 80 degrees. oh and it's also jetted for winter:D so could that make a difference?:uhoh: :uhoh:

also we have the new spark plug ordered and we're picking it up tomorrow so i'll put that in and see if it works better...:ermm: