Plug fouling

[wheels244]

Hello All

Go easy on me - 1st post !!

Ive just bought a 2002 EC250.

Ohlins Forks
Performance PV cover
Gnarly
Pivot pegs
Wavey discs

etc.

I'm very happy with the bike apart from a plug fouling problem.
I've just swapped from an XR400 which was, as you would expect, very reliable.
I knew there would be much more maintenance than my previous thumper. Carrying out the work is no problem to me.

On to the problem.

I've had the bike out twice now, both times on Green Lanes ( trails ).
The 1st time the plug fouled and stopped the bike on a long, slow, downhill section. I had a spare with me and swapped it and carried on.
Today, I fouled the plug twice, again on slow sections.

Can anyone shed any light on this please. I haven't had 2 strokes for over 20 years !

I'm guessing that it is running too rich ? - I haven't touched the bike since I bought it, so I've no idea what settings the bike has, jetting or otherwise.

I've noticed black slooge coming from the PV cover and around the exhaust where it joins the cylinder.

Over to you guys.

Thanks in anticipation.

 

[Brian VT]

Welcome to the site. Don't worry. Not much flogging of newbies here.
Quite a treat coming from an XR to an EC. I came from an XR650R and an XR500R before that.
My EC has been just as reliable as my XRs, but lots more fun.

Your bike certainly sounds rich. Check the easy stuff 1st. Clean air filter ? Clean muffler packing ? Correct spark plug ? Choke fuctioning properly ? Fresh gas ?
Next I'd check for a clean carb, correct float height, jet sizes, needle # and clip position.
I assume the spooge is coming from the PV drain and not by the gasket ?
There should not be spooge coming from the pipe/cylinder joint. I suspect a broken exhaust flange. Most of us here have broken the stock aluminum one and replaced it with a steel one. It's almost inevitable and will surely ruin a good ride.

 

[wheels244]

Thanks for the reply Brian

Clean air filter ? - Not checked, but I'll replace with a new one

Clean muffler packing ? I'll replace

Correct spark plug ? - I've definately got the right plugs

Choke fuctioning properly ? How do you check ? It works in that helps start the bike from cold

Fresh gas ?Definately fresh gas - straight out of the pump.
Next I'd check for a clean carb, correct float height, jet sizes, needle # and clip position. Can you give more advice on this, I know there are multiple answers to this one, I use the bike mostly for trail riding, I think a previous owner may have set it up more for racing - tickover is intermitant, Can you suggest some generic settings for jet size, needle etc for trail riding
I assume the spooge is coming from the PV drain Yes, I believe this is normal ? and not by the gasket ?No, gasket is fine
There should not be spooge coming from the pipe/cylinder joint. I suspect a broken exhaust flange. Most of us here have broken the stock aluminum one and replaced it with a steel one. Can you tell who supplies the steel one please It's almost inevitable and will surely ruin a good ride.

How often do you change the rings ?

It's done about 45hrs since a new piston and rings.

Still seems to have more than enough power, do you just wait for the power to drop off before replacing ?

Thanks again for your help, much appreciated.

 

[JTT]

1. jetting is very personal. Answers to jetting are like eyebrows (filters prevent using alternate, more appropriate term ). First step is to see what's in there now. Then maybe step down a little on the pilot and needle. Also check the float height. The horizontal mold line on the plastic floats should be parallel with the gasket surface of the carb body when the little arm "just" contacts the needle plunger (not allowing the little spring loaded tip to compress)

2. Regarding plugs, I make it a habit to run 1 heat range hotter (NGK "7" rather than the stock "8") in every 2 stroke I've had in recent years. There is absolutely no harm in this unless your planning to run at Bonneville as there is lots of safety margin there. The hotter plug means the tip runs hotter and is more adept at cleaning itself at the higher temps.

3. Steel spigot bits are available from LTR Racing (a sponsor of this site, so links are readily available). Les has shipped to the UK many times, so that's not an issue.

You shouldn't have to think about fouling when things are set up correctly.

 

[dogboy]

244..I have a 1999 EC200 that I bought around 4 years ago...It has been an awesome machine but I also had bad plug fouling problems at first just like you I could go through 2 or 3 a ride...I would say you are just going to have to play with the carb until you get it dialed in...I bet I went into mine 7 or 8 times until I had it right...Its been so long I dont remember exactly what to tell you..... Float level is CRITICAL...Do some research on the different things you can do to lean the carb and experiment, even keep notes...such as adjusting the needle position..changing a size on the main jet..tweaking the low idle air screw....The LTR jet kit is great and if yours does not have it it would be a excellent place to start...Hotter plug, yes... until you get it dialed in carry extra plugs..Run a high quality and probably synthetic 2 cycle oil mixed with premium gas..I use Mobile 1 full synthetic 2 cycle at 40:1 that can even be bought at your auto parts..Auto Zone here in Tenn...Good Luck...

 

[wheels244]

Thanks JTT and Dogboy

I haven't had chance to strip the carb yet - too busy at work.
I will try and get to it this weekend and I'll post my findings on here. Your comments would be much appreciated.
I run fully synthetic Castrol at 50:1, do you recommend changing to 40:1, I'll change the plug to a hotter one.
The LTR kit sounds like the way forward, I'll place my order after I've checked exhaust spigot.

 

[iancp5]

Thanks JTT and Dogboy

I haven't had chance to strip the carb yet - too busy at work.
I will try and get to it this weekend and I'll post my findings on here. Your comments would be much appreciated.
I run fully synthetic Castrol at 50:1, do you recommend changing to 40:1, I'll change the plug to a hotter one.
The LTR kit sounds like the way forward, I'll place my order after I've checked exhaust spigot.

Quality full syn should be fine at 50:1. If I were you I wouldn't bother running a hotter plug it wont need it when the jetting is correct. They don't foul plugs unless something is very amiss so why risk hiding the problem? Speak to either Kev at the GasGas importer, Dave at BikeTech or Liam (when he's on here - he is an automotive engineer and EC200 owner) what is a good jetting for UK. The US jetting doesn't always work well for the UK but it is personal as stated. Anyway those 3 sources can give you a starting position that won't, provided no other faults, foul the plug. Then you have eliminated the most likely cause.

When it is running fine then you can play with hotter plugs etc - though you shouldn't need it then!

 

[RPB111]

My 2001 EC250 was fouling plugs when I first got it. It had the LTR Racing kit in the carb and that was the problem. LTR machines off the markings so you do not know what needle you have. The needle and idle jet were much too rich for the trail riding I do. I went to a K needle with the clip in the bottom slot and 38 idle jet. I left the 178 main jet in and the bike is running fine in cooler weather. Keep records of every change you make and note just what each change does to the bike. Once you have everything right in the carb just a little tweeking is all you should have to do unless you change altitudes.

 

[jlk_250]

This is all good advice. The jetting may take some experimentation to sort out but not to worry, you're probably only a small change away from having it be acceptable. The first step is to find out what you've got at present.

Regarding the exhaust spigot, if it's leaking you may simply need a new gasket and o rings. If the spigot is broken you may opt for a steel LTR piece instead of the stock aluminum one but the stock one is adequate if it's not broken.

Jon
'01 XC300

 

[wheels244]

Thanks guys.

I still haven't had time to get to it.
Altitude is not really an issue in the UK, we don't have the mountains that you have in the states. Where we ride ranges anywhere from sea level to about 1200 feet.

I'll see what I find when I get it stripped.

Thanks again.

 

[wheels244]

Right guys

I've finally had chance to strip the carb.

The main jet is 178.
How do you check what setting the needle is on ?

The float line is not parallel with the carb body before it touches the needle plunger - could this be the problem - how do you adjust it ? Bend the steel that it is attached to ?

Also is there an easy way to get the carb on and off - I had a bit of fight with mine.

 

[Brian VT]

To check/remove the needle pull the spring up from the slide and hold it compressed to the cap. Push the throttle cable down into the slide and off of the recess that secures it. Align the cable so the lead end can be pulled up through the hole in the slide. When reassembling take care that the washer tab seats properly on the top of the slide.
It takes three hands to do this until you get a feel for it. lol

To adjust the float bend the thin metal tab that pushes on the plunger. A little goes a long way.
Also check that the floats are parallel. It's not uncommon to find that they are a bit twisted.

Be carefull not to over-tighten the boot clamps. After you get it all back together run the bike and spray some carb cleaner or ether around the carb boots to make sure you don't have any air being sucked in (lean, not good). Wear safety goggles to be safe.

 

[iancp5]

Be carefull not to over-tighten the boot clamps. After you get it all back together run the bike and spray some carb cleaner or ether around the carb boots to make sure you don't have any air being sucked in (lean, not good). Wear safety goggles to be safe.

What happens does it catch fire? Why the safety goggles?

 

[Brian VT]

What happens does it catch fire? Why the safety goggles?

LOL. I just put that in as a disclaimer. I've probably done it 500 times with no problem but, for some reason, it still doesn't "feel" 100% safe and I'd hate to hear of someone getting hurt because of something I wrote.