Greetings all,
I'm looking at a 1980 300SD to take on as a daily driver. I've previously owned an '84 300D (and though not really relevant, a '66 Mustang with the I6). I only say that to show that I know what a wrench is and I'm not afraid to use one.

I'm primarily looking for the body and mechanical trouble spots on the w116 chassis that I need to be wary of. I've given the car a cursory inspection (and plan on going back with my ramps to get up under it properly)... these are my observations:

Exterior
- Original paint (dark blue) is fading on the high spots (trunk lid, hood and top).
- No sunroof! (I'm VERY happy about that.)
- Window seals are intact and are not dry/brittle/cracking.
- Aluminum trim is all there (but pulling away from the lower corners of the rear window).
- wheel wells, specifically behind the wheels, are rust free.
- rockers & jack points have no visible rust and seem solid. There appears to be a bubble about the size of my pinky nail at the trim under the driver's door.
- hood paint is cracking fairly badly.
- the lower front air dam seam (under the bumper) on the driver's side is rusted.
- front bumper can be pushed in / pulled out about an 1-1/2 inches
- body has it's fair share of dings here and there.

Engine Bay
- entire air cleaner assembly has paint peeling off and is rusty.
- dirty...but no more than what I've seen on other MB diesels
- with engine running and oil cap loosened, the cap stays still
- no rust in the hinge pockets.
- no smells indicating coolant leaks
- valve cover gasket needs to be replaced
- oil pan gasket may need replacing
- nothing leaking out of the coolant reservoir or brake reservoir
- it has a new hood insulating pad

Interior
- driver's seat bottom needs the usual work
- rear seat bottom looks a bit "deflated" but sits ok
- rear seat back at the top (adjacent to package tray) has pulled loose in a couple spots
- package tray carpet is faded
- all mb-tex is intact and fairly clean
- door vinyl/trim/handles is intact and looks good. Driver's map pocket is pulling away from door panel.
- carpets are somewhat faded, but are dry and don't have any funky smells
- dash as a couple minor cracks.
- trunk is nice and dry and no evidence of water stains or funky smells
- Climate controls do not work. Owner spent over $2500 on two occasions within the last two years to fix.
- rear doors won't lock (vacuum I'm sure)
- rear passenger window does the "thunk thunk thunk" when you roll it up. All windows work though.

The drive
- started on second try
- shift knob/linkage is a bit loose
- shifts ridiculously smooth in all gears
- steering was tighter than I expected (better than I recall my former 300D).
- very smooth acceleration
- brakes felt a bit hard
- slight dieseling on shut down.
- I felt like the Dictator of a 3rd World nation driving around
- the windows were down, and I could hear a very consistent rattle that sounded like a heat shield. My impression it was coming from the back end of the engine bay.

Overall, I give the car a 7 out of 10 based on my first impression and drive. The owner described it as "fair condition" but I think it's a bit nicer than merely "fair". From 20 ft away, this car is a real looker. Up close, you can see it's age but there is nothing I found objectionable.

My primary concerns about the car begin with the undercoating it has. I know that stuff is a blessing AND a curse. When I go back and get it on ramps, I plan on using the handle of a screwdriver to tap on every inch of the underside. Are there any specific areas that I should pay special attention to?

It's got some vacuum issues (as do they all). I think the central locking, climate control problems and dieseling on shut off are indicative of that. Under the hood, I can see many new vacuum lines and connectors.

I'm going to ask the owner if he can scan the receipts for the work done to the climate control.

He's asking $5,000 which is high.

Here's a link to photos: https://www.flickr.com/photos/110144767@N03/albums/72157687247905344

Peace,
Norm

I believe that car has the [evil] Chrysler servo-vacuum climate control thing-a-ma-bob. If it is working, and proper MB coolant was used and changed on schedule, you may be ok. If not, then price out the replacement of that component (about $800 or so?) and include the cost in the negotiation.

__________________
Respectfully,
/s/
M. Dillon
'87 124.193 (300TD) "White Whale", ~392k miles, 3.5l IP fitted
'95 124.131 (E300) "Sapphire", 380k miles
'73 Balboa 20 "Sanctification"
Charleston SC

Like Maxbumpo ssid, it looks like it is has the 'evil servo' which can be problematic.

Some areas to inspect for rust: rocker panels (rust through under the sills), floor pans, in trunk under spare and in rear fender pockets), lower front and rear windshields, and beneath the "evil servo".

Don't forget to inspect the condition of the transmission and power steering fluids, steering box play and leaks, date codes on tires,flex plates, exhaust hangers, rear differential mount and shift rod bushings.

$5k is high in view of paint condition, mileage(??), tired interior, visible rust (there is always more), and especially if the AC is not up to snuff.
Ask if regularly driven, currently resistered, back registration due, salvage title???

Realistic price woud be $3,500 (+/- $500) or less if AC "just needs refrigerant".
In the end it's worth what you are willing to pay to acquire it and also bring it up to your standards for road worthiness.

Bring cash in hand, if you are definitiely interested.
Be polite, describe the deficiencies you find, make your offer with the cash on hand - it is a good motivator for closing a deal that the seller may not otherwise accept.

I paid full asking price on my 78 300SD because the R12 AC was functional.
They handle amazingly well for their size and weight.

__________________
78 W116 300SD 'Desert Rose' new as of 01/26/2014
79 W116 300SD 'Stormcloud' RIP 04/11/2022

I went back this past Saturday and spent the better part of two hours going over the car. 40 minutes of that was spent under the car rapping on all the metal with the handle of my craftsman ratchet. Everything sounded solid. I noticed some surface rust on the Rear Trailing Arms... but that's about it... the underside of the car is surprisingly clean.

Other stuff I noted:

Rear driveshafts - look original. Some dry-rotting of the boots. No leaking splits, though.

Rear differential - didn't check oil level, but it has some odd surface rust.

Flex disc - no splits or cracks.

Jacking points - I lifted it with the mercedes jack at all four points. I couldn't detect any deflection/bending along the rockers.

Rockers - closer inspection revealed that some numb-nut put it on a lift just to the interior of the jack points (instead of using the frame rails or subframe). Those areas behind the rockers are pushed in about a half inch.

LBJ's - look new-ish. Boot is still intact, soft and pliable.

UBJ's - brand new. Looks to have been replaced within the last 6 months or so.

Sway Bar bushings front - brand new.

Tie rods - boots blown, but no play.

I pulled back the carpets front and rear. No moisture/water. Knocking on floorboards from top they sound equally solid. The thick almost roofing tile-like material that is under the mats is dry, cracking and coming undone.

Some difficulty starting from cold and smoky. Glow plug light flashes. I'm betting a weak/dead glow plug (or plugs) or glow plug relay.

Injector return lines were leaking like a White House staffer. Easy fix.

There was an odd box in the fuel line up from the in-line filter. It had a single wire that was tapped to a fuse in the fuse box (#6 the cigar lighter / rear window defog... this particular fuse was blown). What the heck is this box?

https://www.flickr.com/photos/110144767@N03/sets/72157687247905344



I did get a chance to look at some records regarding the ac system:

6/22/15 - converted to r134. System flushed and a new compressor (four seasons 58228), drier and evaporator were installed.

8/21/15 - Mercedes dealership replaced the climate control servo assembly and the amplifier. Auxiliary water pump was tested and working. They found that the compressor clutch would not engage (voltage and ground at compressor connector were ok... they suspected a compressor or clutch defect). They concluded that the system was operating as properly as it could in the absence of the working compressor.

I noted there is no belt on the compressor, currently.

(I also noted that the aux fan fuse, #3, was excessively corroded.)

Not sure what to make of that. Could be as easy as a bad connection in the ac clutch OR a whole new compressor.



I'm also concerned about the paint peeling off of the air cleaner and the brake booster (together with the cracking paint on the hood). Does that add up to an engine that overheated at some point? A friend of mine thinks so...



I did find some additional rusty bits... specifically the underside of the passenger front door and at the wiring access on the B pillar, passenger side. I was pleased to find that this was originally a North Carolina car that spent 4-6 years in Rochester, NY. Owner alleges it was garaged and not driven in winter, FWIW. It has less rust than an '84 300D I used to own. (I finally sold that car as the hinge pockets were rusted through... and that's one repair I felt was beyond my ability).


Any further opinions?

Mystery box looks like a cube style fuel pump to compensate for the leaking fuel lines.


Rusty air box, rusty brake booster, rusty PS B pillar, rusty PS fittings, etc... seems like car was driven on salted roads in the winter and not adequately rinsed off before being stored.

Cracked paint on hood, probably driven for a wihile without a hood pad and/or poor paint adhesion from a re-spray of the hood.

Front bumper shocks are blown which means a prior fender bender.


AC not working at present...and compressor not working...$$$ for new compressor and to convert back to R12 or upgrade to parallel flow condensor for R134.

Reasonable offer, with present deficiencies, would be $2,000 to $2,500...if you can correct the deficiences yourself.



If seller balks at your offer...ask seller what they would pay if roles were reversed.
Mention you realize it is worth more than that to current owner due to emotional (blood, sweat, and tears) attachment.

__________________
78 W116 300SD 'Desert Rose' new as of 01/26/2014
79 W116 300SD 'Stormcloud' RIP 04/11/2022

That is showing a LOT of rust...

If you love the car it’s worth it to you. You will be spending more than $5K bringing it up to baseline. If you drive it like it is, it will get worse.

I agree, $2K... good luck.

__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

What are your plans for the car? If AC is a must, I'd hold out for a car with working AC, or something that costs less to accommodate a Sanden retrofit.

https://washingtondc.craigslist.org/mld/cto/d/mercedes-benz-300sd/6338870968.html

https://huntsville.craigslist.org/cto/d/79-mercedes-benz-300sd/6300072206.html

Sixto
98 E320s sedan and wagon

That rust is certainly going to be a nightmare, and it's almost guaranteed to be in more places than you found. I personally would pass on the car even if it was listed for $2,000 just because of the rust, let alone the other issues. It's great that you inspected the car so thoroughly and you should do the same on another prospect.

Well, I'm disappointed but VERY glad to have your collective input.

I went over this car with a fine-toothed comb because my last diesel, an '84 300D, had some daunting rust issues. It's driver's door underside made this SD's passenger door look nearly pristine. Worse yet were the hinge pockets, which had rusted through to the interior. I don't have a garage and I got tired of bailing water out of the floorboards. I really don't want to pick up another car that needs more Rust-Eze (you know, the Medicated Bumper Ointment) than I can afford.

That add-on-in-line fuel pump bothers me a lot... a band-aid approach to a larger problem. As does the fact that the owner, after spending nearly $4500 on the ac, never took it back to have the compressor/clutch issue sorted out.

Search continues...

price is to high,should be no more than $2000 with rust issues. I'd say move to arizona with it,and drive till it quits.

__________________
1999 w140, quit voting to old, and to old to fight, a god damned veteran

https://bringatrailer.com/listing/1979-mercedes-benz-300sd-3/

Not mine, no stake in bidding or sale.

Sixto
98 E320s sedan and wagon

I politely backed out of the sale and am currently looking at an 87 300SDL... but that's another story.

A few days later, this seller contacted me and wants to know what it's worth and if I'd consider $3600. I hate to tell him that $2grand is about it (to a Benz person, anyway).

But I do have two follow up questions: One: Is the rust at the passenger B pillar grommet hole a bonafide structural concern? IE, is that alone a deal killer?

Two: The car does have a ringy sounding rattle under load. I thought it would be a loose heat shield, but I found none when under the car. I talked to a friend (who's a diesel Benz guy) and he suspects the timing chain and/or tensioners. Anyone here agree?

Tell him you don't know what it's worth to anybody else but you're interested at $2000 based on your plans for it, and how much you're willing to lose if there are surprises down the road. Show him $1500 listings that you can get home for under $2000 total.

1) I don't know much about rust but that's an unusual place to have bad rust with few other telltales. If you're really interested, open the door 45* and bounce the far end up and down. You don't want any flex ire or looseness whatsoever. If that's solid and there's no rust on the hinges, the rust can be neutralized and the area braced keeping the b-pillar sound through your ownership. You might have some splainin' to do to the next buyer.

2) That might just be a loose or broken air filter support. As a DIYer, it doesn't bother me.

Sixto
98 E320s sedan and wagon

I politely told the owner I was backing off due to the rust issues. He emailed me back and asked me to make an offer. I did for $2000. We'll see...

In other news, I also walked away from that '87 300SDL... looked like it had the beginnings of rear window sill rot. It was a nice car with a darn near immaculate interior... owner thinks he can get $6500 on a car that Hagerty's says is only worth $4100. Denial... not just a river in Egypt...