Fouling plugs

[catjim813]

All, I have a 69 280sl manual that has been sitting off and on for eight months while doing body work. The car has the 123 ignition and had been running great. It starts up well but is losing power and the plugs are black and wet. I replaced the plugs, car runs great then re-fouls the plugs I am thinking its the injection pump but no problems before.  Any ideas?   thanks in advance.

[w113dude]

Check wires to make sure you are getting good spark at the plugs. coil wire maybe not in all the way?

[badali]

If you are starting and shutting off without driving this could happen.  The engine never gets up to temperature or speed like in highway driving.  The high revs help burn this off.

[ja17]

Sounds like your engine is running rich during cold starts. Check to make sure that your injection pump air filter is not clogged. Also check to make sure that the cold start valve on the intake is not leaking fuel. You should also be using solid stranded copper ignition wire (not carbon wires) and non suppressor spark plugs. The WRD must be functioning properly (check to see if the intake air closes after the engine warms).  Lastly do a split linkage CO test on the injection to see if the injection is too rich during warm up cycle.  Remove shims as required.   Keep us up to date and let us know if you need more details.

Joe Alexander (ja17)
Blacklick, Ohio