Black smoke during acceleration 1965 190dc

[nckmsn]

Is it normal to almost always have black smoke during any accceleration in a 190dc. t seems to put out black smoke even during a slight acceleration. I have heard that these cars do smoke a lot, but I wanted to hear it from someone that really knows. At times the smoke does appear to be white, but is usually black. If this is a problem, then what could be causing it. The car had been sitting for probably 10 years, and then I have driven it about 250 miles. Thanks for your help.

[nckmsn]

I have noticed that when you push the throttle that the air cutoff lever moves up which cuts down on the air intake. After it lifts up, it stays up. Maybe this would cause the smoke. Thanks

[GeoffDuckworth]

Diesels, in general, smoke when they are overfueled. So without being familiar with your car, I'd guess the smoking is the result of air restriction or excess fuel. You might see that the intake is not dirty or restricted in any way: air filter, intake manifold coking, etc.

[t walgamuth]

some black smoke on an old diesel under load is expected. if it is running smoothly and giving appropriate mileage i wouldnt be too worried.

tom w

[KCM]

These models do tend to smoke, especially under hard acceleration. I would definitely check for any restriction in the intake, and make sure the oil-bath air cleaner is clean. There is a full load stop fuel adjustment screw at the rear of the pump which is used to adjust the maximum fuel at full acceleration, and hence smoke output. But it has no affect at partial loads. I would buy a manual before messing with any adjustments on the pump.

There is a vacuum line from the butterfly on the intake to the top rear of the injection pump that controls the fuel rack diaphragm. Make sure this hose is in good shape and not leaking. A leaking line could mess up the fuel/air mixture. I guess you could have a leaking diaphragm as well, as vacuum pulls on the diaphragm (against a spring) which pulls the fuel rack to lean the fuel.

[nckmsn]

thank you for all of the replies. I will look into it and post my findings.

[nckmsn]

any ideas on how to inspect the previously described diaphragm on the ip. Does it require disassembly?

[300SDog]

Probly a good thing you're driving this car. Otherwise the injectors, pump and fuel feed system would fossilize and turn to stone. And based on what KCM said about the diaphragm (thats probly petrified from all these years) I'd go ahead an order the parts from bosch while they've still got em. I think the best mechanical work on the primitive diesel will come from somebody diesel certified to work on tractors and farm equipment - seriously! So dont even bother talking it to the corner garage mechanic.

Meanwhile air/fuel ratios on diesels are only important at the injectors and fuel feed system, as long as inj keep vaporizing fuel without pissing a stream or spitting air into the chambers thats about all that matters. The intake manifold develops no vacuum at all, so dont even go there or worry about the butterfly valve. Black smoke sounds alot like carbon fouled piston crowns to me, could also be injector pump timing. And to clean the oil bath air filter all you need is a scrubrush and kerosene soak - but that doesnt sound like the problem. Heck just rotate it so a fresh section of steel wool faces the opening and it should be fine.

[nckmsn]

what is the procedure for changing the diaphragm? Do you have to oull the ip? What is the name of the part ( diaphragm that I need to order)? Thanks for the help dog

[elipoppin]

I am new and i know nothing......I just aquired a 65 190dc and I have no manual...I manage to change fuel filter but i am sure there is a better method then how I did it....I changed oil but not filter because I wasn't sure how to do it....I just opened the oil bath to try to clean it....I can't seem to find these instructions online very easily....Any links you can offer would be great...

Thanks...

[t walgamuth]

i believe the oil filter on that car is underneath. it is a cannister type. be careful to align the center bolt when putting it back on. it is spring loaded and a little tricky.

the oil bath you just take a rag and clean out the gunky oil, then fill up to the line in the bottom with motor oil. i would use 10w30.

i dont have a book either. so this is mostly conjecture.

but i have had a lot of old benzes.

tom w

[elipoppin]

I got the filter out ok...what a pain...I couldn't seem to find a slot big enough to pull the filter can out...i finally found if i turned the wheels a certain way I could get it out...It had a plastic screen disk on the top but it was so nasty I did not put it back in.....Where do you buy this extra filterand is it stock?? What kind of oil should I be running? I put the reg Delo I use in my duramax...Is that too thin of oil?? I am sure getting alot of smoke....my buddy following me today said it smelled like oil not diesel....I love the car but the massive smoke kinda sucks!!

[Mike D]

You do need that plastic pre-filter. You can clean it up by soaking it in a smail pail of hot soapy water and giving a light scrub with a soft bristled brush.

You could probably clean it with solvents but be careful. That old plastic can react to some cleaners and get very brittle. Those pre-filters are still available.

[elipoppin]

What oil weight should I be using in my 65 190dc??

[t walgamuth]

in the absense of hard info i would prob use rotella 15w40.

tom w