Topic: Wet Black spark plug?

[Meet The Twins]

Only one of my spark plugs is coated in a wet black liquid. Im guessing unburnt fuell because the other spark plug looks perfect. What am I looking at guys? A spark problem or worse?

Then engine was running but rough a few nights ago. The Clymer says to simply switch to a hotter plug.

Thanks

[mlinder]

could be oil. rings and such.

[333]

This is why Clymer is a bad idea.  A hotter plug won't fix a definite problem.  Try doing a compression check.  This'll give you an idea about the rings.  Did you start out with new plugs?  Could be just a bad one.  If all this checks out, it's back to the carbs!

[Meet The Twins]

I started with brand new plugs. The black stuff isnt oily though. It smells like gas.

I was getting a weak spark on that cylinder too. Its always something with this bike. I need to take a deep breathe and maybe bring the bike to a mechanic. Ill play with the spark today and fix electrical stuff and if its not fixed shes off to the shop.

[Gordon]

I need to take a deep breathe and maybe bring the bike to a mechanic.

Don't do it, Man!!!

[Meet The Twins]

Any more ideas guys?  I feels like gas and carbon mixed. The plug wipes clean I think Ill try adjusting my points again to get a better spark. Why would one of my rings be bad on a motor with 8,000 miles?

[Gordon]

Any more ideas guys?  I feels like gas and carbon mixed. The plug wipes clean I think Ill try adjusting my points again to get a better spark. Why would one of my rings be bad on a motor with 8,000 miles?

If it's black with soot and wet with gas, then it could be a carb problem, as in too rich.  The carbon fouling may have caused the plug to stop firing consistently allowing it to get soaked with unburnt fuel.

[333]

If the spark is weak on that one wire, then you may have a bad cap, or connection where the cap "screws" onto the wire.  "Unscrew" the cap from the wire.  Inspect carefully.  Some caps can be disassembled.  Look in the spark plug side.  If there is a slot for a screwdriver, it may unscrew allowing the metal innards to come out.  The connection to the wire is what looks like a sheet metal screw "screwing"  into the center of the wire.  Clip the wire back 1/4 of an inch to get a fresh connection.

[Uncle Ernie]

What kind of bike?  Do you have 1 carb, or 2?  1 or 2 coils? 

A hotter plug will do nothing to help.  Sounds like it's getting too much gas, air delivery could be messed up... Nothing too difficult, just time consuming.  Depending on how you value your time, I see nothing wrong with going to outside help.  Personally- I only work on bikes because I have to.  Unfortunately, that's fairly often....

[cb350f_rider_73]

Just to help elaborate on the bad spark plug cap theory, another test is to get a digital multimeter, set it to 20k ohms, then test the cap itself.  Your average cap will read at about 5000 ohms or so.  If it's too much more (in the neighborhood of 7000 or more) you probably have a bad cap. 

Hope it helps,

Wayne