Honda Discussions about Honda ATVs.

400ex fouling plugs?

Thread Tools
 
Search this Thread
 
  #1  
Old 03-31-2008, 07:50 PM
99_400EX's Avatar
Trailblazer
Thread Starter
Join Date: Mar 2008
Posts: 37
Likes: 0
Received 0 Likes on 0 Posts
Default 400ex fouling plugs?

new quad to me. It's a 99 400ex. It runs great. I've only rode it enough to maybe use up a tank and a half of gas. Today I had flooded it out and had to put in a new plug for it to start. This is the second time since I've had it. So I'm on my third plug in only my second tank of gas. The original one I was trying to start when it was pretty cold out but today was 60 gegrees. As I stated before it runs great, doesn't smoke but when I pulled the plug out today it was black (carbon?). I'm wondering how long a plug should last. I have a Clymer's manual and may try to adjust the carb but it runs and idles fine. Oh yeah, I bought it with K&N filter, HMF slip-on and it has been jetted but I have no idea what jets are in it. I have read about putting in a 42 pilot jet for better cold starting. Any other tips??????? My first thought is maybe it's running rich, but I don't notice any smoke.
 
  #2  
Old 03-31-2008, 09:30 PM
MIwolvy's Avatar
Pro Rider
Join Date: Mar 2007
Posts: 266
Likes: 0
Received 0 Likes on 0 Posts
Default 400ex fouling plugs?

mine does the exact same thing, and I'm the same situation...less than 2 tanks if gas, and bought it modded. My battery is a little weak, and I have fouled the plug a few times because of the weak cranking, plus it doesn't help that I have tried to start it in the cold every time.

I can't help you with the problem, but just to save a few bucks...hit the fouled plug with some steel wool and re-install it. Works for me every time.
 
  #3  
Old 04-01-2008, 11:55 AM
99_400EX's Avatar
Trailblazer
Thread Starter
Join Date: Mar 2008
Posts: 37
Likes: 0
Received 0 Likes on 0 Posts
Default 400ex fouling plugs?

K thanx, anyone else? This can't be normal.
 
  #4  
Old 04-01-2008, 01:59 PM
jrafter's Avatar
Pro Rider
Join Date: May 2006
Posts: 543
Likes: 0
Received 0 Likes on 0 Posts
Default 400ex fouling plugs?

they do go through plugs but i got a AMR coil and a sparks rev box and dont have that problem any more
 
  #5  
Old 04-01-2008, 02:00 PM
jrafter's Avatar
Pro Rider
Join Date: May 2006
Posts: 543
Likes: 0
Received 0 Likes on 0 Posts
Default 400ex fouling plugs?

you also cant use the choke ..just pump the throttle couple times and it will start
 
  #6  
Old 04-01-2008, 03:05 PM
hondabuster's Avatar
Elite Pro Rider
Join Date: Dec 2003
Posts: 5,599
Likes: 0
Received 0 Likes on 0 Posts
Default 400ex fouling plugs?

Easy on pumping the throttle. The stock carb has an accelerator pump, and if you use the throttle to start, its very easy to overdo it and end up with a flooded engine.
Try just using the choke, when starting cold. If it doesnt start, with in a few seconds of cranking, then use about 1/4 throttle, but dont pump....just hold it steady. Movement, is whats makes the accelerator pump discharge.
You could try an iradium plug..they resist fouling alot more than standard plugs do.
 
  #7  
Old 04-01-2008, 06:25 PM
99_400EX's Avatar
Trailblazer
Thread Starter
Join Date: Mar 2008
Posts: 37
Likes: 0
Received 0 Likes on 0 Posts
Default 400ex fouling plugs?

Cool. Thanx for the replies. I probably have been using the choke too much and definitely have been using too much throttle. I think I'll keep this new plug in and change my starting habits and see how it looks in the near future. I will see about changing the pilot before next winter but I hate to tear into the carb yet as it runs and idles great. Thanx again.
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
XxS0ccerstarxX
Honda
2
10-18-2021 10:03 PM
XxS0ccerstarxX
General Chat
0
08-07-2015 06:18 PM
cornermike
Polaris
1
07-30-2015 06:37 AM
metal249
Honda
1
07-28-2015 09:35 AM
metal249
Honda
1
07-24-2015 01:00 PM

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 


Quick Reply: 400ex fouling plugs?



All times are GMT -5. The time now is 01:17 PM.