Hi everyone! New member and new '72 280SE 4.5 owner

[Baxterdown]

Hi everyone!

I’m the proud new owner of a 1972 280SE 4.5. And, since I know the protocol on discussion boards, first things first. Click here for the pics! :p:

I’m loving the car; it’s in great condition. Most stuff that it needs is either cosmetic or minor mechanical. It runs amazingly well and the interior is in fantastic shape.

Of course, I have A TON of questions. I don’t have an owner’s manual (planning on buying one), but for now here are a few inquiries:

• What is the proper position of the Defrost sliders to make sure that it is OFF?
• What do the two knobs on the bottom of the gauge cluster do?
• The gauge cluster light is out, how do I replace the light bulb(s)?
• What does the knob between the light switch and the speaker balance knob do?
• Can the A/C be upgraded, and if so can anyone can share their experience after upgrading? I’m in Florida and the A/C doesn’t seem able to keep up in this horrible summer heat.
• The steering wheel has A LOT of play. Any ideas?
• And last but not least...
• One headrest is straight up and the other is bent forward. I cannot move them to save my life! How can I adjust them?

Any help or feedback is greatly appreciated. And, I’m looking forward to being an active participant on the forum

Jose

[124Coupe]

Great looking car and welcome Jose.

To answer some of your questions, the upper left heater switch is for the blower, upper right diverts air to the windshield or floor and the lower two control the temperature on their respective sides. During the Summer, I have all four towards the middle.

Beneath the gauge cluster, the left dims the instrument panel lights and the right resets the tripmeter.

There are a handful of bulbs in the instrument cluster which is a bit of an ordeal to remove (search). Once accessed, replace all of them for good measure.

The knob between the light switch and fader with a white dot is for the heated rear window. It should illuminate when you pull it on. Pull it again and it should go off.

My 4.5 still runs on R12 and properly working, it gets quite cold. I would shy away from modifying the system if still original.

[billhard]

Great looking car! Yours appears to be very well optioned, the armrest alone make me jealous.

According to info I have found on this site play in the steering could be a number of things but often is a bushing in the coupler between the column and the power steering box. Search w108 steering for more info.

The headrests have a hole in one side with a philips head screw inside that tensions the movement. Be careful not to take the screw all the way out, if i recall it's a pain to get it back in.

Cheers.

[Baxterdown]

Guys, thanks SO MUCH for your responses!

124Coupe

• I'm gonna follow your lead on the defroster positions. It's 94 degrees down here right now
• The left cluster knob turns and turns, it also pulls out (feels like its spring loaded). But no lights come on.
• The right cluster knob is stuck. I don't need to reset the speedo so I'm not gonna touch it.
• I searched how to remove the instrument cluster. It looks like a weekend project. Gonna add it to the to-do list.
• The rear defroster knob pulls but no light comes on. I can't tell if it's working as the temperature is pretty high right now. I'm gonna leave that one for another day.
• Thanks on the A/C advice. You're the second person who tells me not to modify it. I think there is definitely something wrong with mine though. Gonna have it checked.

Billhard

• I met a great mechanic who specializes in MB today. Great guy and he came highly recommended! Indeed, he said the steering coupling bushing is gone. He's gonna fix that and the reverse horn problem that just started yesterday (I'm not comfortable taking the steering wheel apart yet). He estimated 3 hours of work ($300 total). Well worth it!
• I tried to fix the headrests but I don't seem to have a Phillips screw in there. I hit it with a flashlight and the screw looks more like an hex bolt. I'll take another shot at it tomorrow.

Thanks again guys; appreciate it!

Jose

[pj67coll]

Beautiful car. On your steering play. Probably just what the mechanic said but from my experience and given that you live in Florida make sure that there is no sign of rust around the steering box mounting position on the chassis box frame section. Also make sure the three steering box mounting bolts are torqued to spec. Snapped steering shaft is no fun.

- Peter.

[berfinroy]

Two comments regarding the ac. The system will definately work better with R12 that 134a, but even at its best its not as powerful as most modern systems. That said, I found that when I removed the lower dash panel to replace a faulty fan reostat that the foam material used to seal the cold air plenum had completely disintigrated with age, thus allowing cold air to leak out under the dash in various places rather than all coming out of the cold air vents. The foam that Mercedes used in that era for certain padding and other purposes was not chemically stable; every bit of it has now virtually disolved! (Check out your "B" pillars; the covering is now limp and loose because the underlying foam padding has disintigrated)

[Baxterdown]

Thanks guys!

pj67coll
I'm counting on this mechanic to know how to torque to specs. His shop is 100% MB driven--that's all he works on. Also, the person that recommended him said he knows classic Benzes well. -- Thanks for the advice, I'll have him check for rust.

berfinroy
Yes, definitely the A/C needs work. I'm gonna check the cold air plenum foam material. Thanks for the suggestion!

[billhard]

Originally Posted by Baxterdown

Billhard

• I tried to fix the headrests but I don't seem to have a Phillips screw in there. I hit it with a flashlight and the screw looks more like an hex bolt. I'll take another shot at it tomorrow.

Thanks again guys; appreciate it!

Jose

Yeah could be a hex either way that's the ticket to headrest adjustment.

[vandor]

>What is the proper position of the Defrost sliders to make sure that it is OFF?

The two lower levers control the heater for the left and right side of the car.
The red triangle denotes less or more head, more heat toward the larger part of the triangle. So to shut the heater off, those two must be moved toward the center.
The upper left lever controls outside air. Again, look at the triangle, blue in this instance. You get more air toward the larger part of the triangle, ie. toward the left. The last ~1" of travel makes the fan come on, it has 3 speeds. So for the fan to be off, move the lever toward the left until you feel a little resistance. When you engage the fan you will feel the lever engage into a notch. There are 3 notches for the 3 fan speeds.
To get no outside air into the car, move it to the right.
BTW, you can also control outside air going directly to the left round vent with the lever next to that vent.
The right upper lever determines where the air comes out - push to the left to defrost and to the right to get air to the floor.

The w108's HVAC system is a bit weird, as the Heat and AC systems are, I believe, separate. AFAIK you cannot get AC'd air to the defrost vents, or heat to the round side vents. The heater either blows to the windshield, or to the floor.
The AC system is also plumbed into the left vent's fresh air inlet, so if you have the AC on make sure you close the fresh air inlet with the lever next to the left round vent.
My AC blows mostly from the middle vents and very little from the side vents.
It has been converted to r134a by the PO, and it works OK, but not great.

BTW, nice car!

[Baxterdown]

Billhard,

It was a hex screw indeed. A 10mm hex to be exact (see attached). I loosened both sides and the headrest adjusted back and forth beautifully. Hope this info helps someone else.

Thanks again!