W126, BENZ AID - COMMON QUESTIONS AND ANSWERS

1983 300SD Turbo: Light black smoke at idle

The symptom is unburned fuel at idle. A light puff-puff of black smoke -- not heavy, but visible, at 700-750 rpm with car in gear and A/C on. Much less smoke when the tranny is in neutral, A/C off, and engine is idling at 800 rpm. The presence (or absence) of an air filter has no effect. Except for this bit of smoke, which is embarrassing at stoplights, the car runs and shifts great. 0-60 in 14.5s, and I measured 10 psi boost during hard acceleration. On long trips getting 20-22 mpg (milage verified with GPS).

Chassis Model Number

W126

Forums

Diesel Engine Specific Aid

1985 300d diagnosing transmission leaks ??

I have developed a transmission leak, originally i thought it was the pan gasket so i replaced the filter and put on a new gasket. that didnt work it is still leaking. i think it is comming from where the dipstick tube goes into the transmission, or maybe the transmission cooler line, i have tightened the cooler line and it still seems to be leaking. if anyone has any sugestions i would be most greatfull.

Chassis Model Number

W123

Forums

Transmission / Suspension Specific Aid

85 300CD no charge to battery

I'm not getting charging to the battery. I have replaced the voltage regulator on the alternator (the old regulator brushes where about worn out), but did not get any change in the charge to the battery. At idle, voltage to battery shows 11.9v and dropping. When rpm increased, voltage will increase to 12.35v max, than right down below 12v when back to idle. What am I missing?

Chassis Model Number

W123

Forums

Diesel Engine Specific Aid

1984 300D Boost fuel pump routing

I have a single tank wvo conversion on a 1984 300D. I currently have the following fuel routing: Fuel tank to pre-filter to boost pump to vormax fuel filter to heat exchanger to stock system. Is there a problem with me putting the vormax filter first, then the pump? In other words, is it ok if the pump pulls through the filter instead of pushes?

Thanks.

Chassis Model Number

W123

Forums

SVO Fuel Conversion Specific Aid

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