Hi All -

Thanks for the forum I am sure it will make my life easier. I just picked up an 84 300D 78K, Grey on Tan from the original owner for 400.00. It a great car but I need to do a little fixing. I brew my own B100 and it is a good high quality fuel, my 6.0 Ford f250 loves it and it passes all the tests I have run it through. So I a not new to diesels just the MBZ

The Good,
Runs and starts like a top
New Battery
New Tires
Perfect body no accidents
Good Interior No rips or tears

The Bad
Oil leak
Vacuum Leaks
AC Compressor is dead
Needs an alignment

What I need help with is how to troubleshoot the vacuum system, I have downloaded the diagrams but I really have never done any vacuum work so

How do I test them ? What tools do I need ? and what should be my results ?

The current symptoms are poor trans performance / hard shifts, no HVAC control other than all hot all the time, door locks don't work but trunk lock does.

Any help would be appreciated.

The oil leak will be fine I am cleaning the underside of the car tomorrow to trace the leak as it is currently an oily mess and I want to clean it up before I try to find the leak.

As for the AC I will R&R the compressor and have the system emptied any thoughts or tips on an R134 conversion for this car ?

I look forward to sharing ideas

regards,

Tr0y

Welcome, Tr0y. You got a sweet deal on your 300D - mine was a ton more than that, and probably not in as good of shape (not to mention about 4x as many miles).

Check out DieselGiant.com for good ideas on some starter maintenence. Also, be sure to utilize the search function on this site....you'll find lots of good info on the vacuum system issues. For what it's worth, I'm having almost identical vacuum issues on my 84.

Enjoy.

__________________
1984 300D: 275,000 miles (soon to be for sale)

In search of my 1987 300D in anything but white.

You need to purchase a hand vacuum pump with a guage to trouble shoot the vacuum system. Mighty Vac or similar. The plastic ones are a poor investment but will get you by for awhile. I bought my last brass one on sale at the local Sears.

R12 can still be purchased but it is costly. IMHO it's worth the extra cost as it cools much better in the W123 system.

Use the google forum search tool and do some reading. Most of the questions you will have are already answered in great detail. Also look at the DIY pages on this forum for the repair issue.

__________________
Charles
1983 300D, bought new, 215k+ miles, donated to Purple Hearts veterans charity but I have parts for sale: http://www.peachparts.com/shopforum/mercedes-benz-cars-sale/296386-fs-1-owner-83-mb-300d-turbo-rebuild-parts.html

an 84 300D with only 78K for $400.00? I hate you already Just kidding of course.

that is great, how did you fall into a deal like that?

anyway, welcome to the forum. start reading, listening, asking questions, do some searches, sit on the side line when things start heating up and see where it goes. In no time you will armed to take on anything. You will be dangerious with knowledge..

stick with R12 for better cooling. up grading to a Parallel flow condensor will also help with better cooling.

Charlie

__________________
there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

I agree.... Diesel Giant has some great Pictorials/tutorials on the vacuum and A/C stuff.
Welcome aboard.

__________________
"Those that turn their guns into plows shall serve and tarry for those who do not." Thomas Jefferson

If you can't stick with R12, then you can use freeze-12, which is a blend. I highly recommend replacing the compressor with a brand new Hodyon (Hancock Ind) compressor. I have had bad luck w/rebuilt ones.

There are tons of write ups you can use.

I do recommend a Mity-Vac to chase the vacuum leaks.

Also go ahead and adjust the valves and perform the EGR bypass that Brian Carlton wrote up. It's easy, and your engine will thank you for it.

Welcome aboard, and I wish I had the find you have!

__________________
RRGrassi


70's Southern Pacific #5608 Fairmont A-4 MOW car

13 VW JSW 2.0 TDI 193K, Tuned with DPF and EGR Delete.

99 W210 E300 Turbo Diesel, chipped, DPF/Converter Delete. Still needs EGR Delete, 232K

90 Dodge D250 5.9 Cummins/5 speed. 400K

Gone and still missed...1982 w123 300D, 1991 w124 300D

a lot of these cars have leaking door lock systems by now.
both my car and the engine donor had already had the door lock system (yellow/green stripe) hoses disconnected near the brake booster by the time I got them. the brown line is your engine shutoff. the red line is your cabin air control.

__________________
'82 Euro MB 300 D Turbo Silver/Blue - Fixed
Adding W115 Intake and Intercooler

1986 Chevy Camaro Cp 400HP For Sale
Engineer
Tuscaloosa, AL

Thanks all for the info, I appreciate it and Ill report back on progress and post some pics.

Thanks

Tr0y

yeah thats quite a steal.. I agree!!!! How are your brakes? Do they stop the car with little ease or does it require a great deal. Vacum pumps are problems but easily fixed with patience. Shifting hard is sometimes "normal" as they are noted for hard shifts from first to second especially. I'm not sure if it's your first Diesel Benz or not. The modulator draws its vacum and control from the little "black box" on top of your valve cover. The switches in there mimmick changes in manifold vacum you'd find on your gas engine. I like the others here.. have seen tons of disconnected vacum systems in these cars. The fact you have multiple problems.. I'd start at the pump and work and work my way back. There is a black approx half inch diameter line running from just behind the power steering pump back to your brake booster. Off there runs two lines that control your shut off and the other vacum related items. Best of luck with your "steal"... We ALL envy you!!!!!

Fast navigation Do It Yourself Links
Fast navigation Do It Yourself Links






Enjoy.

__________________
ASE Master Mechanic
https://whunter.carrd.co/

Prototype R&D/testing:
Thermal & Aerodynamic System Engineering (TASE) Senior vehicle instrumentation technician.
Noise Vibration and Harshness (NVH).
Dynamometer.
Heat exchanger durability.
HV-A/C Climate Control.
Vehicle build.
Fleet Durability
Technical Quality Auditor.
Automotive Technical Writer

1985 300SD
1983 300D
2003 Volvo V70

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