New-to-me 240D

[Prospector]

Hey guys, I just picked up a 1981 240D that comes with a few expected quirks. This will be an adventure as it is my first Mercedes and first diesel. The previous owner posted here and other places so some history on the car may be available to me online if I can track down his posts.

The car is in overall very good shape body-wise. I was looking at cars that would rate a 4 to 5 on my scale of condition, but for a couple grand more, I decided it was worth it to get a strong body and decent mechanicals and hope it all pans out.

What I have noticed so far:

1. Odometer sticks (saw the repair at diesel giant - not too scary) - $0 to fix
2. Engine has blowby - teakettle test had oil spray all over and rad cap really jumping. PO says a valve adjustment will help - I am not sure when the last one was done. Is it worth it to buy the kit, or just the wrenches? Engine may be worn. Not sure. Swap??? - $180 for valve adjustment kit with wrenches, gasket, feeler gauges, etc.
3. Oil pressure gauge is pegged to the top while driving - I don't know what the normal position for the gauge is. Rings shot? Sensor bad? Gauge bad? (Could be pricey - dunno)
4. The dash is all original - including radio. But no lights work except the dim speedo bulb. I think I can get bulbs for the heater gauges, but how do you light up the radio? - $20 in bulbs
5. Power windows don't work for the back seat. Any common problem I should know about there? - No idea, likely an electric fault
6. Driver's door lock has vacuum issue (you can hear the vacuum fail when you unlock the door). Not an issue - can fix over a weekend. - $30 part, $30 vacuum tester
7. Power antenna only goes 1/2 way down. any ideas for a fix there? it looks straight, but is pretty gummed up. Last car I was able to just clean the antenna and then it worked. - worst case is replace power antenna - $40
8. The engine is pretty shaky, so it wouldn't surprise me if it needs new motor mounts. - $100 in parts

Are there any recommended checks I should do or have my mechanic do for me while he's under there for the "state" inspection (we're in Canada here, so its provincial). All I could see lying on the ground with a trouble light was possibly a tie rod end, and one strut had a lot of grease around it, but not sure if it was a sloppy lube job or the strut had failed - but I am not a mechanic.

[JB3]

welcome!

(you should have this thread moved to the diesel discussion, lots more traffic for your 123 there!)

oil pressure gauge pegged is normal, should drop to 2 bar or half way mark at idle. Pegged when engine is at load is good. If it were to drop while driving, id immediately pull over and shut it off.

Lots of your problems are still broken on mine as well.

Id play with dimmer switch on the dash. There have been a bunch of occasions where I got my dash lights to work just fiddling with that switch. It may have a few corroded spots

[barry12345]

Toronto area is not as bad rust wise as the east coast of Canada. Still bad enough to cause serious issues. You have to get these cars up on a hoist and check them carefully.

[Prospector]

Thanks guys - JB3 - the speedo light works on both settings (dim and faint) but the heater knobs don't light up. Nor does the radio. It was fun driving it home for the first time and guessing what knob did what. We froze.

I'm not sure how receptive this crowd is to x-posting. Am I better to post a link to this thread in the diesel forum, or to just cut-paste my first post in this threads?

Barry - our family mechanic has it for safety now. I'll hear from him in the morning. he's a pretty straight I shooter, so whatever cancer he spots, I know I'll hear about. I wasn't able to spot much at all with trouble light while rolling around on the ground.

[Idle]

Originally Posted by Prospector

Thanks guys - JB3 - the speedo light works on both settings (dim and faint) but the heater knobs don't light up. Nor does the radio. It was fun driving it home for the first time and guessing what knob did what. We froze.

I'm not sure how receptive this crowd is to x-posting. Am I better to post a link to this thread in the diesel forum, or to just cut-paste my first post in this threads?

Barry - our family mechanic has it for safety now. I'll hear from him in the morning. he's a pretty straight I shooter, so whatever cancer he spots, I know I'll hear about. I wasn't able to spot much at all with trouble light while rolling around on the ground.

Just post your first post to that thread. No one here seems to get to shook up over cross posting as there is a lot of overlap in knowledge from one area to another.

[Left Coast]

Sounds like you have a dead lamp or two in the dash. Radio has its own lamp, probably dead too. The dash light is supposed to be infinite adjustment, but the pot that Mercedes used in those years was never any good. At brightest setting it is barely adequate for well lit city driving when all the lamps are working.

Blowby at that age is normal. When the oil cap flies off the valve cover, then you have serious blowby! New engine mounts will help with engine shakes, but have the injectors serviced as well. After that, check and adjust the base idle and adjust valves. You should be able to find a new VC gasket, feeler gauge set, and adjusting wrenches for a lot less than $180.

Good luck with the car. You'll come to love it, as long as you are not in a hurry to get anywhere. Let us know where you found a power antenna replacement for $40. I'm sure that I'm not the only one that's interested.

[Prospector]

thanks Left coast - on this site, if you do a parts search for my car you can get the antenna mast for $40 without the motor. motor on mine fires which suggests a cleaning and lube is all that's needed, but the mast may be required if wd40 and repeated cycles doesn't break through the grunge.

On my last old car, once i got the antenna moving freely I lubed the mast regularly with synthetic chain oil from my bike. (Pedro's synlube) it kept it moving nicely without picking up any dirt.

[Left Coast]

You might get away with a replacement mast if the old one still moves a little bit under power. If you can hear the motor going and nothing moves at all, then you'd better crack open the motor/gearbox before you order a mast. Those things have several vulnerabilities, and replacement parts for the internals are quite limited.

[Prospector]

Yes - I have about 10" of travel. Likely the mast is just goobered up.