W123

Valve Adjustment Oddity

In adjusting my valves on my 300D nonturbo I am perplexed with an odd occurence. After adjusting a valve to the right gap and tightening the lock nut and adjusting nut, I check the gap again and all is good. But when I use a wrench to spin the valve stem using the two nuts, which turns the valve stem and the spring assembely, the gap changes, even though the nuts are tight. It will get either tighter or looser, but if I keep spinning it it will return to my original adjustment. That is if it gets tighter, by spinning it further it will eventually loosen up.

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Biodiesel additives needed? + warnings

I converted the fuel lines on my '82 300DT and plan to run B100 biodiesel consistently. I heard about the need for adding lubricity to low sulfer petrodiesel but does anyone know if too low of lubricity is a problem with biodiesel? The only fuel addative I have used so far is a product called "Killem" to clean out the fuel tank.

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300D turbo running hot

What is the normal running temp for my 83 300D? Right now it gets hot quickly and moves up above 90C and will approach the 120C point if I run the AC. I've changed thermostats and flush the radiator and put in new coolant along with a water wetter. Seems to run somewhat cooler but not what it should be. The electric fan used to come on but doesn't now. What is the most common thing I should look for if the fan doesn't come on? Thanks, Dan

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W123

A/C Comes on and off periodically

I have an 81 240D and when I turn on the A/C the compressor will kick in and it will blow really cold for a while only when the the analog dial is in the max-a/c position. However periodically it will kick on and off with no real reason behind it. I don't think it's the switch b/c moving it up and down does not fix the problem. It seems as though some part of the system decides its had enough and stops for a while. Anyone have a problem like this? Thanks.

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W123

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Diesel ign. switch problems

I have never really understood, on our 123's, why I have to return the key all the way counter-clockwise if the engine fails to start. Strange voodoo with the vacuum shut-off? A peculiarly odd tuetonic accomodation for the hearing-impaired? What prevents it from functioning. Every now and then I have trouble with the switch stopping before the crank position, no matter what I do. Is this something that popping the cylinder and spraying WD40 would help? It is so intermittent that I could go for weeks without it happening again, or I could get stuck at the drive-up tomorrow. Thoughts?

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transmission compatibility? 1979 300sd to 1980 300d

hi, i have the excellent guide on how to replace transmission, and am about to try this with my dad. he has the transmission out of the parts car, a 1979 300sd, and the torque converter wouldn't come with it (broken timing chain so no turning over). before we take out the badly slipping transmission from my 1980 300d, we're trying to determine compatibility issues. any known problems?? any help much appreciated, thank you! -noah

Chassis Model Number

W123

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