I just bought this 1990 300 SEL:

Untitled by ttownthomas, on Flickr

I live in cary NC

The car is from California and has 109,000 miles on it. From the looks of the paperwork it was owned by the original owner until 2 or 3 years ago. It appears that the car then transferred to the daughter of the owner (mabee he passed). It has been very well loved. The paint is glossy and the interior is nearly perfect. The last owner donated it and the dealer I bought it from got it from an auction. Then sold it on bring-a-trailer.

So far my punch list of broken stiff is pretty small:

The on-off buttons on the Becker Grand Prix BE 1480 light up but nothing else works. When you press the "on" button nothing happens

The antenna is stuck half way up and bent. It also makes no noise whatsoever even if you pres the up and down switch on the dash. I assume this cannot be troubleshot until the radio is fixed

There is a broken plastic collar on the cold air intake tube.

The wood veneer needs redone

The driver seat bolster has a hole and I think the seat springs are broken

This is my first Mercedes-Benz. Im Excited

Chris

Current:
1990 MB 300SEL
1990 Volvo 240. 5.3LS swap in my home garage
1987 Porsche930 Coupe

Past:
1987 Porsche 951
2004 BMW 335i
1985 Porsche 911 Targa 3.2

Hello and welcome to the forum Chris - I'm guessing that you're already signed up on our Pelican Part forum from your various Porsches. This community is just as knowledgeable and helpful; so please feel free to post any inquiries. As with our Porsches, we have a vast DIY tech article section - I'm attaching the W126 one for you. Welcome!

https://www.pelicanparts.com/techarticles/MBZ_Tech_Index-W126.htm

Yes on the pelican forum.

Thank you for the heads up on the diy section!

The radio probably needs a code but it would display CODE if waiting for the code. They probably disconnected the antenna power wires to keep it from trying to retract continuously. Replacement masts are available for OE antennas.

Did the car come with service history documents? If not, checking and replacing fluids and filters is a good way to get to know the car. Authorized and bootleg CDs of barely passable factory service manual scans are available. Or spend the money on printed volumes if you’re a DIYer. Oddly, the CDs don’t include transmission service volumes.

Mike Murrell on this forum was particularly helpful when I had a ‘91 300SE.

Sixto
98 E320s sedan and wagon

I remember that car on bring-a-trailer, congrats! And like Sixto said, start with all the fluids, filters and do a coolant flush and replace the green stuff with the right Mercedes approved coolant.
There is so much information out here and on the web about the W126 in general or the M103 engine. I've tackled a lot of things myself on my 1990 300SE, including a head gasket and front suspension with the help here or the information I found on the web.

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1979 Black on Black, 300CD (sold), 1990 Black 300SE, Silver 1989 Volvo 780, 1988 300CE (vanished by the hands of a girlfriend), 1992 300CE (Rescue).

Lol. It does have the green stuff in it. Thanks for the pointers. I plan to replace all the fluids, filters and fuses first.

According to Metric Motors it ruined the head on my 300SE with only 90K miles.

__________________
1979 Black on Black, 300CD (sold), 1990 Black 300SE, Silver 1989 Volvo 780, 1988 300CE (vanished by the hands of a girlfriend), 1992 300CE (Rescue).

The radio was still connected correctly and the multi tester says it has 12 v at all the right places. I sent it to Becker to get repaired and delete the tape deck and put a blutooth module in its place.

How do I know I am getting a Factory service manual. I am a DIYer. Is this one:

https://www.ebay.com/itm/MERCEDES-SERVICE-MANUAL-CHASSIS-BODY-126-300-380-420-500-560-/191779994657

That looks like a factory service manual. I haven’t heard of bootleg hard copies. But that’s just one volume. There’ll be an engine volume, chassis and body volume, transmission volume, electrical volume, maintenance volume... maybe others like the model year introduction volume with information not found anywhere else. MB has about a foot tall stack of factory service manuals for any model of the vintage.

If you don’t mind printing a few pages or getting a PC dirty, you can use the engine section of this site - Model 124 Maintenance Manual Index

There is a 300E bible or two available for the engine section, and contrary to purists I found the Haynes W124 manual (not printed in US) was good enough for engine tasks. Don’t expect much on CIS function and troubleshooting beyond won’t start. FWIW, the Haynes book also covers Diesels which is useful when you graduate from the 300SEL to a 300SDL. Most of the factory volumes cover the SDL as well, you’ll just need the OM603 volume in place of the M103 volume.

Sixto
98 E320s sedan and wagon

Why is that considered a graduation? <-(not intended to be defensive or snarky)

I was being snarky. I had a 300SE and a 300SDL at the same time. I’ll let you guess which I preferred. It’s more about second gear start than engine capability.

Sixto
98 E320s sedan and wagon

Gotcha, Lol.

I couldn't help myself. The tires were shot and the Tirerack website talked me into these 16's

Untitled by ttownthomas, on Flickr

Looks good!

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1979 Black on Black, 300CD (sold), 1990 Black 300SE, Silver 1989 Volvo 780, 1988 300CE (vanished by the hands of a girlfriend), 1992 300CE (Rescue).

X2. Wheels look great. Much better than the chrome 15" 15-holes.

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Watch him go!!! link

#dontdealwithkahlil