Too rich for my blood

[abruzzi]

My previously perfect running steamer (1995) suddenly started running rough.  First I thought the old coils might be the culprit, then I noticed that if I revved it, it would shoot black smoke out the pipes.  What is most likely the cause, and please don't tell me I'll need to pull the carbs....

Geof

[JetdocX]

Pull the carbs.  Just get it over with.  Even if it's a clogged air filter, the carbs still need to be removed.  Time to pay for your Steamer ownership with a little sweat! :lol:

In the future consider a pre-filter on the airbox ends.  They make air filter cleaning sooooo much easier.

[aeronca]

 just do it man :shock:    then check your valve clearance.good luck, and stay thirsty my friend

[Rocinante]

You don´t have to pull the carbs as a first measure, try everything simple first. It has been said on this forum by far more tech savvy folks then me, that most problems that you believe relate to the carbs are electrical problems, one way or the other.

- Pull plugs and check for sparks
- Start up and let it run on idle for a little while. Check how warm the pipes are. If one is a lot less warm than the other two, go to next. (one safe way to check the pipes is to throw water on them, on the running ones it evaporates immediately)
- Swap coils between the culprit cylinder and a good one, start up and check the pipes again to see if the problem moves. If it does then the problem is the coil, if not it´s most likely to do with carbs.
- If it doesn´t move, swap plugs between the problem cylinder and another, check pipes again. If it moves it´s the plug.
- If it still doesn´t move, swap the plug cable between a good and the bad cylinder. Again, if the problem moves the cable´s the unlikely culprit.

If not:
- Check the air filter. When I used a K/N re-washable filter it used to suddenly stop functioning, and the symptoms where the same as yours, rough running and lots of black smoke. A quick wash and fresh oil and it was back in business. The original seems to take a lot more dust and dirt before giving up. That´s why I went back to it.

If all this to no avail you might pull the carbs. But if you suspect a jet to be clogged, then - correct me if I´m wrong please - it wouldn´t blow black smoke. I just recently had that problem with the pilot jet, and it didn´t smoke at all, it just ran poorly up to a certain throttle position.

[abruzzi]

FYI, I'm avoiding pulling the carbs because the tank has developed a spun nut, and it all becomes a big to-do.  If I have to pull the tank, this probably won't be getting fixed for several months.

Geof

[Mustang]

one way or another you are going to pull the tank.............

[Bixxer Bob]

[Rocinante]

Nice song.  8)

Actually I think you can easily remove the tank with one of the side panels still attached, or else just grind off the bolt head and leave it. I have a tank nut that has been left like that for ten years. Lots of hold in the remaining bolts.

[BruKen]

Let's be clear. Black smoke or brown smoke?

Brown smoke carbs and or ignition

Black smoke valves pistons and rings

Ja hey, nog n YAPI :D