81 240D

So over the last few months, I noticed that when i turned the steering wheel to the right as part of a turn, the car idled very rough. I would put my foot on the pedal to up the RPM to go to high idle and it would smooth out. it was only when I was turning the steering wheel. now it got worse that idling all the time is very rough. i was thinking engine mounts, but i had recently done then and when I checked, they were holding up fine, no tears.

Not sure how it was only happening when turning, but it was odd for sure.

Thanks

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Grey '91 350SDL 214k Dad's car
Beige '81 240D 4 Speed 254k SOLD
Blue '82 300D 225k SOLD
White '95 E300D 46k SOLD
Blue '87 190D 2.5 Turbo 315k SOLD
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Blue '85 300D Model 186k T-Boned

More load on the engine from the power steering pump?

other things that cause shaking: worn engine shocks, bad injectors, compression problem

Sounds like engine or transmission mount issues. Did you use Lemforder or OE MB mounts? The cheaper brands only last a year or so before they become soft. Don't discount the transmission mount or loose exhaust components. Some 240's have an extra "T" mount that is known to cause noise as well.

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When was the last valve adjustment?

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84 300D, 82 Volvo 244Gl Diesel

Lots of potential reasons unfortunately. A valve adjustment and a compression test in that order is a good starting point. Look for movement in the mounts as suggested even though they are new.

Has the problem remained over a few tanks of fuel? I'm wondering if you got a batch of stale fuel.

Good luck!!!

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"Rudeness is a weak man's imitation of strength" - Eric Hoffer

The T mount Dieseasal mentioned is at the oil pan....on the side toward the rear end I believe. It fits into a socket in the cross member and will make a load of noise if worn and hitting metal to metal. It also makes trouble when swapping a 3 liter.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

I can pretty much guarantee that it's something rattling. Might be the air cleaner. Might be loose engine mount bolts. But these engines vibrate like crazy, something you won't notice until a part is translating that into noise. You would notice it more going around a corner because the engine would shift slightly to the side that has something rattling.

In my case it was the air cleaner, which had lost the piece of rubber hose isolating it from the valve cover at some point (a PO upgrade). I seriously thought there was an earthquake when I started the car.

But start with the harder stuff if you'd rather. Maybe pull the engine and swap the conrods out.

it is not just a rattling, but more that the whole car shakes when at low idle. if i had a full can of soda sitting bolted to the dash, it would shoot it out like crazy. i know the normal slight rattle might do it a tiny bit, this is teeth chattering.

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Grey '91 350SDL 214k Dad's car
Beige '81 240D 4 Speed 254k SOLD
Blue '82 300D 225k SOLD
White '95 E300D 46k SOLD
Blue '87 190D 2.5 Turbo 315k SOLD
Brown '80 240D 4 Speed 716k SOLD
Beige '80 300D N/A 119k SOLD
Blue '85 300D Model 186k T-Boned

That sounds exactly like when my air cleaner was rattling. It was like someone was jackhammering the car.

I'm not saying you don't have some other issue, but don't underestimate the power of these engines to shake the earth until it splits open.

A video would serve to clarify things a bit I think.

The procedure has you turn the wheel hard over thereby loading the engine with the steering pump while adjusting the idle/throttle stop adjustMent screw to compensate. If I recall it even includes turning the ac on high to compensate for that additional load. If you don’t follow that procedure you’ll probably shake with any load. The 616 is especially sensitive to equipment loading as would be expected. When the glow plugs are on I drop at least 100 RPM. If you’re under spec idle your shakin and quakin.

So as I started to take a video of shaking, i opened the hood and saw that Injector #4 was cl leaking. Will try to get the video uploaded, but this is makes more sense now.

__________________

Grey '91 350SDL 214k Dad's car
Beige '81 240D 4 Speed 254k SOLD
Blue '82 300D 225k SOLD
White '95 E300D 46k SOLD
Blue '87 190D 2.5 Turbo 315k SOLD
Brown '80 240D 4 Speed 716k SOLD
Beige '80 300D N/A 119k SOLD
Blue '85 300D Model 186k T-Boned