I'm looking to buy my first torque wrench to use when working on my 240D. I need recommendations on what to look for and what this work will require.

There is a large bolt on the front of the crank that tightens the damper there. It requires 200 lbs torque. I have had to rent a torque wrench with that scale to get that one set. Sort of depends on whether you are planning on replacing the front seal or not, but that is a consideration. $ort of pricey for the big torque wrenches though.
Other than that, there are other good tool pros here that will steer you right.

I torque wrench is the one tool where you always want to put quality and accuracy ahead of price.

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85 300CD
83 300TD
78 240D (daughter)

If you can find one, an old Proto click adjust. They're a Richmond/Sternavent(sp?) design and "were" the best out there.

Mac tools also makes a good click wrench in the 50-250 range if you need that high.

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1984 300D Turbo - 4-speed manual conversion, mid-level resto

1983 300D - parts car

1979 300TD Auto - Parts car.

1985 300D Auto - Wrecked/Parts.


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"If you don't know where you are going, any road will get you there". Lewis Carrol

The most accurate torque wrench on the market happens to be the cheapest one it is the type with the scale running horizontally across the top with a pointer a plastic handle that you must keep straight with the main bar that runs vertically and the little pointer points at the scale which is marked from 0 in the center increasing in foot pounds as the pointer moves to the outer edge see attached picture not only is it cheap but it is more accurate than a $500 snap on click wrench or any other bar none let the argument begin but be prepared I can back up my claims with well proven scientific facts And even my Saturn owners manual says so. But the aircraft industry has spent a ton of money on this and the simple cheap one wins by a mile.
Dave S

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That may be the most accurate type.... and that is the only type I have.. both ft/lbs and in/lbs....
But it is not easy to use correctly in tight spaces...
I wish I had a ' pretty good' click type myself...

I just assumed click-type as that is what more people use now days. You are correct in that a manual torque wrench is very accurate, but you still have differences between the cheap and expensive ones. The aircraft industry (at least the bigger manufacturers) use different kinds and usually have torque testing machines on hand to regularly test their torque wrenches. Us mechanics just usually send them off once a year to get re-calibrated.

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85 300CD
83 300TD
78 240D (daughter)

This is the kind of information that I needed and thats why the ? I assumed the more expensive models were better and didn't know that others would need to checked for accuracy.

Another consideration is that the "click' type of wrenches usually ratchet. The "beam" type do not.

A bolt is really a spring and when you torque a bolt what you are really doing is adjusting how much you are stretching the spring to preload it.

People tend to approach this with awe, magic and BS. It is not rocket science. Almost any decent torque wrench is adequate for your use.

I would buy a cheap 1/2" drive torque wrench and shop for a little better 3/8" drive that measures inch/lbs.

Now for the flame bait: As a teenager working in a motorcycle shop I was taught how to torque bolts by feel without a torque wrench. It can be done, I have checked myself with a torque wrench and I am pretty accurate. I use a torque wrench on critical parts anyway.

I don’t know about jet liners the biggest plane I ever worked on was a Lear jet got to fly it for a minute too what a blast. But in a general aviation shop be it light planes or helicopters you would be reprimanded or even fired for using a click type torque wrench. And I know since at least 1996 major automakers have been moving away from the click type wrench Saturn strongly advises against there use. The click type torque wrench is wildly inaccurate and does not even really measure torque as in clamping pressure but is much more likely to measure friction between fasteners. Why are we evan talking about somthing as outdated as tourque wrenchs when we should be using degrees of rotation
Dave S

One reason is because all the shop manuals specify torque settings, and mention nothing about degrees of rotation. The MB shop books all show the "manual" type torque wrenches, just for what it's worth.

There is a lot to be said for developing the "feel" for how tight is enough. I try to use 3/8 drive for just about everything except the really big stuff, it's usually harder to overtighten with a smaller handle.

Kevin

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'85 300SD

Well, I know a bit about overhaul and maintenance of jet engines and every single overhaul shop of large turbofan engines uses the click type torque wrench. They are calibrated on a yearly basis and the accuracy of these wrenches is about 1 ft.-lb. or so. The accuracy of the traditional bar wrench may be better than the click type, however, the traditional wrench is fraught with the risk of operator error. It is virtually impossible to for the average mechanic to operate the traditional wrench to an accuracy of 1 ft.-lb.

I use a Snap On and I recommed it if you want to spend the money. They last forever and Snap On will check it any time you want. I just had it done back in March.

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1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200

“One reason is because all the shop manuals specify torque settings, and mention nothing about degrees of rotation. The MB shop books all show the "manual" type torque wrenches, just for what it's worth.”
I don’t know what manual you are reading but my hard copy MBZ manuals all specify angle of rotation for critical joints such as head bolts bearings ect
The FAA specifically recommends against the use of click type wrenches for aircraft use I can look it upand quote chapter and verce. They do prefer the use of the new model TES or equivalent such as the snap on direct reading torqometer wrench it can be held at any angle without affecting accuracy because of this and other factors they are preferred over beam type torque wrenches. I don’t know about big jet engines but on small planes torque means just about didily squat for critical joints. Who cars if your bolt is torqued on at 800 ft lbs if your clamping pressure is 0 lbs it will simply fly apart no matter how much torque is on the bolt if it has no clamping pressure which is what degrees of rotation and stretch to fit bolts assures you.
Dave S