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220SEb smoker

I recently bought a '61 220SE coupe w/2 plunger and in the process of trying to get it to run smoothly. It belches continuous whitish smoke with occassional black soot upon startup but gradually thins out (still continuous) as the engine heats up. When really hot, the engine stops smoking at idle but appears as you rev to shift around 3000 rpm. I've run the car daily in the hope that the valve seals would sit properly but no improvements. Is this something related to the injection pump adjustment or the valves/cylinder head? Should I try different oil / additive combinations? All help and comments greatly appreciated.

Reply to
corix
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These smoke signals are symptoms of a head gasket problem. No combination of fuel and oil makes white smoke. White smoke upon start up is from coolant that's leaked into the exhaust being burned by the exhaust heat. Black soot could be from oil seeping into a cylinder or misfiring due to a wet plug or over fueling. Any oil in the coolant and or coolant in the oil?

Suggest you remove and inspect the spark plugs after the engine has stood over night. One or two may be wet with coolant and or oil. If nothing found, briefly crank the engine without the sparkplugs installed, then inspect the spark plugs' holes for expelled fluid(s). If still nothing is found a compression test is the next diagnostic step on this path short of removing the cylinderhead.

It's not what you wanted to hear but may be the reason for the smoke.

Reply to
T.G. Lambach

Further thought: When shutting the motor down for the day, loosen the radiator cap - carefully, it's hot - to relieve the cooling system's pressure that's forcing the coolant leak. In the morning tighten the radiator cap and start the motor - if there's no white smoke the head gasket diagnosis has one additional confirming clue.

Reply to
T.G. Lambach

Tried it out! Very little white smoke (less than before) upon initial start-up and idling. However, greyish-blue smoke showed up near operating temp. It was really noticeable (thick) when revving from idling. I haven't checked the plugs as I'm resigned to the fact that a cylinder job is in order. I just hope it won't include the pistons/rings.

Incidentally, I got rid of the black smoke during warmup by turning a screw at the left side of the base where the coolant thermostat is mounted. I assumed it was running rich and turning the screw leaned it out. My FI is an early 2-plunger with a separate air thermostat from the coolant thermostat (in contrast to newer 6-plungers). Can anyone out there with knowledge on this type of pump validate whether my guesswork was on the right path? Thanks and appreciate your help.

Martin

Reply to
corix

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