This is a long post, if you’re in a hurry skip on by.

I need some advice or a reality check on keeping this car. (84 300D, 237,000 miles)

It was originally driven by my mother-in-law from 84 to 91, then purchased by our neighbor, who always wanted a Mercedes diesel. My son, 4 years old at the time, asked our neighbor: “Ed, when you’re finished with grandma’s car, can I have it?” I don’t remember Ed’s response. Ed drove the car for about eight years then parked it in a garage (dirt floor) and it sat for the better part of the next six years. Ed passed away last summer, his son and daughter called to confirm my son was home and came over and signed the title over. “Ed always said this car was to go to you,” they said to my son. Very tearful. In November 1994 this vehicle had 26,000 fewer miles on it then it does today.

We parked the car in my in-laws barn (cement floor this time) for the winter and finally got it out about a month ago. I studied this forum carefully over this past winter and spring and have taken much away to utilize on the vehicle. Thank you to all frequent posting participants!

Here’s the good:

I have all service records since new, along with window sticker.
Vacuum system seems to be great, door locks & ducts working fine.
Engine not smoking (for a diesel of this vintage).
Engine starts quickly and reliably (with it’s new battery).
Glow plugs test OK.
Alternator & VR test OK.
Block heater tests OK.
No fluid leaks (so far).


Here’s what we’ve fixed (with the help of this forum):
Battery replacement.
Replaced brake hoses.
Replaced LR & RF calipers.
New pads and brake fluid change.
Oil & Filter change.
Fuel filter(s) changed.
Differential fluid change.
Re-attached wood trim at center console and glove box.
Re-attached vinyl to pillar and pillar to frame at drivers seat belt (not sure why this was off).
Replaced hood pad – most rested on engine.
Replaced air filter and filter housing bushings.
Repacked front wheel bearings.
Four new tires from Sam’s Club – Goodrich Touring T/A – I am still waiting to hear back from their general manager about restoring my exhaust system.

Here are pending issues:
Still need to troubleshoot vacuum regulator to attempt cure of 2nd to 1st “clunk” on downshift.
Engine Mounts.
Subframe mounts?
Ball joints?
A/C doesn’t work – maybe just a charge?
Rust – this car has been in Michigan all of its years. Nowhere near the WHUNTER pics but still has rustthrough at LF jackpoint, rust at remaining jackpoints, rustthrough below front bumper at seams in front of horns, rust and/or rustthrough at wheel wells. Rust beginning at RF door weatherstrip, rust beginning in trunk wells. Imagine what the engine compartment looks like with eight years of heat/cold cycles stored in a garage without a floor! We’ve treated quite a bit with Eastwood’s rust encapsulator and brushed over with a close match from Finishmasters. I’m certain this car’s mechanicals will still be functional long after the body is shot.

What am I hoping for?

Reliable transportation. My son will take his Jeep Cherokee to Houghton during the college term. My daughter might drive this vehicle unless there’s snow flying, then she’ll drive the family van and I would drive the 300 (rear drive + snow). Use it until it dies? Will it be unreliable and a constant pocketbook drain?

Or – My son has a few buddies from high school that are interested in it. Do we sell it in the hopes of getting our money back + a few $?

What do you think? Any suggestions?

Its always nice to know the history of a car. You've done well in that respect.
You also seem to have a car that runs well, with the exception of the downshift issue.

Of the items on your list, the motor ( as well as transmission) mounts are not too bad. Actuallt the tranny mount is very easy. The motor mounts can vary from tedious to aggravating.
The big issue, as you know, is RUST. I personally prefer to sand blast rusted areas before treating with a product like Eastwood.s rust encapsulator. I tend to worry more about rust in ct inside the box sections? I have considered doing that on other cars--I even decided that a pair of rubber gloves and a sponge and some wire were the tools I would use. (Thread the wire thru the box section, saturate the sponge and pull it thru). I am not certain I could get complete coverage, but I think it would help.
Read the posts about A/C. These cars were designed for R12 and are not great candidates for R134 conversion. However, in Michigan you may get away with it. If you do, please make sure all the R12 has already been lost, or have it professionally removed. Do not mix ( and contaminate) any remaining R12. If you decide to use R134, do it right--not quick and dirty.

Keep us posted on your project.

you have PM.

Look at my location..

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whunter, I'm in Kalamazoo. It would be great to have you give my vehicle the "once over" but I'm not over on the East side very often any more. Perhaps sometime this summer my son & I could drive over for a visit?

you have my contact info.

Has anyone cut open the area around a jack point to see what would be involved in restoring a really badly rusted out jackpoint ? Or just reinforcing one which is ' going south ' ?

only thing I would suggest is checking the timing chain and adjusting the valves.

Regarding the rust, this isn't gonna be a show car, so convert the rust and bondo the hell out of it, then use a very heavy hand with the rustoleum and undercoat. Actually, I don't use undercoating any more, I use 'truck bed coating' in a spray can, works great, really tuff, really clings hard to a recently powerwashed surface.

good luck,
Robert

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Cheers,
Robert

My 300CD was originally from Erie Penn. so I can relate to your car. Great running, great interior, but rusting a little bit everywhere. As far as the rust, I've been using POR-15. It's nasty stuff, but it works great. The inside of the frame has lots of wax from Benz, so basically all my problems are from the outside. Hopefully this is the case with your car. If your forward jack points are bad, chances are you may also have lower cowl rot. You can check on this by removing the plastic fender wells in the wheel well. If there is a hole in that frame shelf, you can get a good view of the jack point from the inside. As far as filler for holes, I've been using some heavy gauge steel with aircraft epoxy over the POR-15 & it looks like it never rusted.
On the exhaust, look up Timevalve.com on the net. They manufacture stainless steel exhaust for these cars for something like $500-600. somewhat more than a regular steel exhaust. Paul, central Florida.
1984 300CD Red ext. black int. 288,000 miles

your rust may not be that bad. the sheet metal right at the jack points seems to be a little thin. have you tried jacking it up carefully? if the jack tube doesnt bend much it may be just fine and the thin metal around it just rusted out. anyway if it is weak you can jack from several other strong places with a floor jack or the like. you have a good start on sorting the problems out. when you get them done it should provide good transportation. of course on a car this old there will always be things going off,, but you just have to keep fixing them.

if cared for reasonably the mileage is not at all a problem.

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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.

You do all that work on it and now you want to sell it???

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1984 300SD Turbo Diesel 150,000 miles

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this is a good safe (kids and MB's belong together for this very reason) car, a few tweaks and it may very well be a reliable daily driver.
I would take the advice on the valves, take a look at the chain and run her until she dies, you may be suprised that it will out last all of us LOL

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Ron
2015 Porsche Cayman - Elizabeth
2011 Porsche Cayman - Bond,James Bond
Sadly MERCEDESLESS - ALways LOOKING !
99 E320 THE Queen Mary - SOLD
62 220b - Dolly - Finally my Finny! Sadly SOLD
72 450SL, Pearl-SOLD
16 F350 6.7 Diesel -THOR
19 BMW X5 - Heaven on Wheels
14 38HP John Deere 3038E Tractor -Mean Green
84 300SD, Benjamin -SOLD
71 220 - W115-Libby ( my first love) -SOLD
73 280 - W114 "Organspende" Rest in Peace
81 380 SL - Rest in Peace

keep working on arresting the rust, but drive it! Some folks are way too hung up on rust, IMHO. If the car leaks water to soak the carpets or is stucturally unsound, that's a serious problem. Little holes in the doors or rockers is not.

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'82 300SD - 361K mi - "Blue"

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