really slow until warm?

[240dddd]

I finally got my 84 300TD OM617 turbo diesel on the road and am starting to take care of some of the quirks...

The car is really sluggish for the first few minutes of driving when it's cold, then as it gets warmer, usually 2-3 minutes into driving, the boost will kick in all of sudden and then everything is fine. Until that point the car feels slower than a 240D.

The thing is I'm pretty sure I can hear the turbo spooling even when it's cold, so I don't really understand why I'm not feeling any boost?

[jabstick420]

Mine is the same

Don't know the reason. But definitely more pep when warmed up

[tyl604]

My SD is the same; always has been. After a minute or two on cold days, it wakes up.

Is yours really a TD - a wagon? If so, how about a pic.

[240dddd]

yes, it is a wagon. I don't currently have any pics, but she's not particularly pretty anyway Kind of a long term project to make her a reliable daily driver so I'm focusing on the mechanics more than cosmetics.

[Junkman]

There are links to adjust the turbo back to factory boost. Perhaps hood up a gauge so you're not guessing.

[unkl300d]

Very cold temps outside?
Proper motor oil weight?

[240dddd]

not extremely cold. I live in seattle so it is generally above freezing. I use liquid moly 15w40

[NZScott]

Welcome to the world of old school diesels.

Diesels need heat to combust the fuel, and when the engine is stone cold, not all the fuel combusts properly, so you don't get same power Modern diesels allow for that with the computer controlled injection.

[jake12tech]

It's an older IDI diesel.. This is not news to anyone. It should warm up 5 minutes before you drive it. I never just jump in my diesels and just drive them. You also don't idle them for extended periods of time or "lug" them. You will build up carbon. Diesels need to be driven, and IDIs like to rev so if you run it at 4500 RPMS, its not beating on it by any means. It needs it once in awhile. People around here call it an "italian tuneup".

[dieselbenz1]

I had that problem on my old 617 dog slow when cold out. After I put in new injectors that problem disappeared and I no longer had to warm it up.

[240dddd]

Actually it's not my first rodeo with a w123, i've owned a '77 240D and an '85 300D Part of the reason I ask is that the 300D didn't have the same issue that I remember, at least not as extreme. I usually took it easy until the 300D warmed up, but as a comparison the 300TD feels like it's towing an anchor until it starts warming up whereas the 300D felt normal.

[HershalM]

May be your batter is weak. How long are you using this?

[Diseasel300]

Battery has nothing to do with how a diesel engine runs once it's started.

Is it possible you're getting air in the system when the car sits?

[240dddd]

I though I had followed up here, but apparently not...

I spent some time adjusting the throttle mechanism which helped a bit. This weekend I changed out the thermostat because it seemed like the engine was never getting warm enough, usually hovering around the lower quarter of the thermostat. With the new thermostat the engine warms up to 80c quickly, and the turbo starts coming in strong after about a minute of driving.

The thing I don't understand is that when the turbo starts working it's like a switch being thrown, i.e. mid acceleration it will be creeping along then all of a sudden the turbo kicks on really strong. There is nothing gradual about it.

[bricktron]

let me second the suggestion to connect a boost (pressure) gauge. then you will be able to see how intake manifold pressure rises and when.