New 1976 (115) 240D (for me anyway) - PeachParts Mercedes-Benz Forum

piccolovic · #1 03-25-2003, 01:51 PM

Well sports fans, I brought home a $500 240D which was leaking oil, fuel, and power steering fluid like a seive!!! Got the leaks fixed before I left LA to return to Montana. This car is basic manual everything, and no A/C. Put used injectors that were tightened and tested for psi and the engine is quieter and black smoke went away. However, now I still have white smoke and lousy mileage and still using some oil. Any suggestions besides STP additive? I also replaced all the fluids in 4-spd trans, rear end, oil in engine, replaced all filters, windshield wipers, front brake pads, drained the cooling system and replaced the rusty water with real coolant at 70% which is recommended for my weather, etc.

The car feels solid, doesn't shake and drives cool. I still have questions that my limited manuals don't answer.

I seem to have a rear window defrost system that I don't know how to turn on. Where would the switch be, if there is one. I don't know if this year came with one and mine in simply a replacement rear window.

Also, I have a complete 190D 2.2L, 5-spd drivetrain. What would it take to put the 190D drivetrain on this body? Is it more trouble than its worth?

Oh, the color is horrific -- butterscotch. There is some rust, but not too bad. It does need an alighnment, but does not shimmy right now, just lightly pulls to right when braking. Tires were in excellent condition with aggressive tread, which was a surprise for no-name brand.

What are the three or four positions for on the ignition switch? It has a pull-switch for the starter. Which position is for the glow plugs? Right now we rigged up a Montana glow plug system by putting in a push button activator for the glow plugs.

Dash lights don't work and already tried replacing the bulbs. Any known common way to fix this?

Any other suggestions on checking/replacing as part of bringing home this big ??? car with unknown history?

I appreciate any helpful hints I can get, especially if they're cheap to do.

Thanks,

Vicki
piccolov@3rivers.net

diesel don · #2 03-25-2003, 03:39 PM

I suspect that your white smoke and mpg are related to Injection Pump Timing issues. You are most likely exhausting unburned fuel.

Probably the timing is off and may be off due to excessive stretch in the timing chain. Keep an eye on Michael LaPleur on the forum as he is working through this very issue.

Don

JimSmith · #3 03-25-2003, 03:52 PM

Vicki,

I had one of these, picked it up new at the factory in January of 1975. Drove it until the body fell off and the engine was still running strong.

First, there is a switch on the center console of the dash for the rear defogger. I believe it is a knob you pull out against a spring load, and the center of it lights up. After a period of time, like half an hour, it shuts itself off. This may not be accurate as my memory may be failing; it has been a few years since I put that vehicle out to rest.

The key switch for setting up the starting and running operations is pretty simple. I know it has some detents for energizing the dash lights, exterior lights and so on, but as I recall you turn it all the way clock wise and leave it. Then you grab the starting knob on the left side of the steering wheel. When you pull it out to the "run" position it opens the fuel supply valve to the injection pump. If you try to pull it further out, against a spring load, you should see the interior lamps dim, and, after 30 or 40 seconds, the little glow plug indicator (a filament behind the screen above the steering column) will begin to glow. You hold the knob against this spring pressure until the glow plug indicatior gets pretty much yellowish orange, then you pull harder and the starter is engaged. As long as you hold the knob out in the "start" position, it will keep the glow plugs glowing while cranking the engine, but not the one on the dash used for indicating the state of preheat.

On my car the pull knob switch stopped working in the "preheat the glow plugs" position. My car had a switch on the shift lever that disengaged the starting circuit if the car was not in neutral. But it did not disengage the power to the glow plugs. So, I would put the shift lever in gear, then pull the knob out for 30 to 40 seconds, and then push the gear shift lever into neutral. The glow plug preheat indicator on the dash would not light up but the glow plugs on the engine worked fine. The car would start cranking as soon as I put the car in neutral, and then start right up.

The dash lights may be a fuse. Check the fuse box, the cover should have a key to the fuses. In a car that old, it would not surprise me if the fuses were a little corroded. I might just buy all new ones and replace the old ones after cleaning the contact surfaces.

Your oil consumption may be due to a number of things. If the smoking is worse at idle, you may have a vacuum pump diaphragm that is leaking. It is also possible the car just uses and possibly leaks oil. How many miles?

Based on what I have read on this forum I would suspect the timing chain and injection timing should be checked as well. Good luck, enjoy the car, Jim

diesel don · #4 03-25-2003, 04:19 PM

Jim Smith brought up an interesting point about the diaphram leaking. I would check that before the injection timing. The diaphram would be much easier and was a common problem.

Don

kchemers · #5 03-25-2003, 08:51 PM

The dash lights dont work because the dimmer switch is probably worn out. On the dash to the left of the turn signals is a black knob. This is the rheostat that dims the lights. I have the same car with over 250000 miles on it. I bought it in Texas and drove it straight thru to Chicago with out a problem . Great car and fun to work on. The dimmer switch is available from fast lane for $30. I havnt replacerd mine yet, but I do get enough light to see the gauges. As far as oil consumption, I dont have any leaks and I use a quart every 1000 miles or so. Make sure you change both fuel filters and carry spares with you. Great car ugly color.
Kchemers

joshhol · #6 03-25-2003, 10:45 PM

Quote:

Oh, the color is horrific -- butterscotch.

I suspect one of the reasons you don't see a lot of these 115's is because Mercedes was experimenting with some of the most unfortunate color schemes they ever attempted. They must have been into some american fashion magazines or something.
Another reason is probably the uncharacteristicly short production life of these models. 2 years is not the norm is it?

Get the valves adjusted. It's one of the best things you can do for an old neglected benz. It's also cheap or easy enough to do yourself.
Look at Thomaspin's thread on this forum, it's right up your alley.

So you think this car is big??? I don't know about that. I step into a honda coupe and I get and begin to fear for my life, esp on the freeway.
Good luck with this beast and thanks for keeping another 115 out of the junkyard. Definitely look into that chain though, it'll ruin your engine if it goes.

Love my 115.

dabenz · #7 03-26-2003, 06:20 AM

Vicki, you're going to like this car.

Best bang for the buck is the CD offered at this site (they also give us a great forum "free").

I think your next step should be to replace (not just bleed) the brake fluid. The clutch actuators (same fluid as brakes) should be bled backwards after bleeding the rear brakes. Look at rear of brake master cylinder where it connects to the big vacuum disk: rust or peeling paint may be a leaking master cylinder. Look at brake disks: solid rust streak may be sticking caliper piston, spotty rust may be a warped disk (cheap). Also check that the parking brake releases fully.

Then adjust the valves and check timing chain stretch while the valve cover is off. Then check the throttle body/governor system (this is where the CD becomes a cheap item). Black smoke went away after injectors done, so they're probably ok? I use Rotella 15-40 oil, and only halfway up the dipstick (the rest goes out the rear crank seal), and PowerService fuel additive (white or grey bottle). The white smoke may be timing, an injector pump that loosened up due to "low" sulfur fuel without additives, vacuum related, or a head gasket. Exhaust smells normal? Turn the fast idle down when engine warmed up?

Work the dash light dimmer back and forth a few dozen times with the headlights on.

Good luck.

Fisherman · #8 03-26-2003, 10:06 AM

Just a couple other little things of note. On the 115s the rear defroster switch is to the right of the stereo in the center console. You pull it out to turn on, it is spring loaded adn boucnes back. To shutoff manually you push it in.
The light for this switch is in what looks like a plastic plug on the right (passenger) side of the cente console. Gently remove the round plastic plug and you will see the light bulb there.

Dash lights can be regained by hotwiring them (check the threads) or working the switch a bunch of times or replacing the switch as noted earlier.

My ignition switch has one position for unlocking the steering wheel, one for accessoriy power and then on. I have not noticed another position. I have all my owners manuals so if there is anything speciic let me know and I can look it up.

The starting procedure outlined above is spot on. In cold weather you can glow for up to sixty seconds before starting.
When my car is only mildly warmed up I still have to glow for 10 seconds or so sometimes. This is not a car to jump in and run to the corner store...

Check a couple of things for the smoking in addition to the items noted above.
There is a vacuum line that runs from the back of the injection pump to the intake manifold. Make sure this line and the banjo bolt connection at the manifold are not plugged. If you have a vacuum tester, test the fitting on the back of the IP to see if it holds vacuum. If it does not you need to replace teh IP diaphragm. I have yet to do this on my car but it appears to be fairly straightforward.
DO NOT run the car with this vacuum line disconnected! The motor will start to run away without it in place (at least mine did).

I love my 115 as it is so simple... Have fun!

One other thing: The 115s start out in second gear from a stop. It is really aggravating if you need to get out of a driveway or something into traffic. The solution is:
When you are stopped pull the shifter into L position and this will downshift the tranny to 1st. You can then put it back into S before taking off and the car will shift normally through the gears starting in 1st and going up to 3rd. If you floor it the car will jump (well as much as a 240 can jump). Also when climbing a steep street in the city you can pull the shifter into L after you have started moving and it will hold the car in 2nd gear for maintianing your speed while climbimg a hill. Believe me you will need this at times...

piccolovic · #9 03-26-2003, 11:54 AM

1. I replaced all the fuses while in LA as part of road-trip prep.

2. today, we are doing compression test, checking the timing chain, and after that, possibly adjusting (manually) IP.

3. ?there are two fog lights (w/o bulbs) that have different lense covers -- will they automatically come on when I replace the bulbs? or is there a different mechanism to turn them on?

4. To our friend in ND, are you the one who had the 190 body w/o an engine? If so, do you still have it, and do you want to still unload it? I'm near Three Forks, MT.

5. The local mechanic, who thinks he's not a fan of MBZ actually seems to like working on this car!! On the test drive, he actually complimented how sturdy the car was driving and said I basically got a good car for the $500. I have to tip my hat at the amount of yankee ingenuity these guys use (such as taking apart my bad injector to weld together a fitting to do the compression test!!!)

6. Thanks about the info on the rear defroster, I thought that switch was a map light!!!! (uh, don't quote me on that, but so did my LA mechanic who owns an identical one!!!)

7. I have tried the dimmer switch a couple of times, but I'll do it a dozen or so more times to make sure. I noticed that after getting in and out of car a cozen or so times, interior and glove box lights started to work as they should! Apparently, this car sat for at least two years.

8. Vacuum pump -- is that on the engine, belt-driven, above the power steering pump, with a hose that goes to the cylindrical air thing on ari intake? How would that be checked/fixed?

9. On the IP issue for the drip test method -- there is one row on top, which the fuel goes into the injector hoses. Can the valve and spring be removed from under the hoses without changing the internal pressure settings on the pump itself, or do I need to use another method? (This is only after timeing chain and valve adjustment issues/diaphram issues are dealt with).

10. Does anyone have the mm/inch adjustment specs for intake/exhaust for valve adjustment (warm)? I used to adjust valves on gas engines many years ago and was pretty competent at it (they used to drag me out of the parts dept at work to do them cause they said I had a feel for feeler gauges!!!!), and the manual looks pretty straight forward on this, although I can see, that like the slant six, I may need to constantly be careful which are exhaust vs. intake!!! I'm not sure I trust the manual I have for the specs.

11. Regarding placement of 2.2L ('84) deisel drivetrain on this at some later point, would we have to change all the mounting to accomplish this? It appears to have enough room under the hood for the conversion, but welding new mounting systems for tranny and engine would be a pain, that would cost too much. Or by any chance, did MBZ make compatible systems like GM did for all their V-8 engines, making swaps easy?

12. Copies of owner's manuals??? Heck yes, -- what would it cost for xeroxing and mailing?

13. Oh, this car is a manual, with 4 speeds.

13. What mpg gas mileage should I be getting from this car?

14. Regarding the stick shift boot -- there are two types, one that fits on a plastic frame (as with my 190D) and one that fits on the existing built-in rising lip on the console. Sounds like you got the later model rubber boot. The other car you talked about may be aftermarket leather -- check the many deals on JC Whitney for the leather ones, they may actually be nicer.

Finally, you guys have been super, and I look forward to continued communication with you and letting you know how the bucket continues to adventure on in life!!!

Oh, and finally, check out the '69 300SEL 6.3 I'm selling in the "cars" section if anyone wants a 90% restoration muscle-car.

Vicki

dabenz · #10 03-26-2003, 01:48 PM

#4 & #11: Not me, but you might be missing an engine and transmission if I find a little pickup body before you find a MB body!

#8: Front left of engine. Hose from brake vacuum reservoir to pump, from pump to air intake. If power brakes work then pump works. If there is another tube from back of injector pump to throttle body then you have a vacuum operated governor (not hooked up to vacuum pump).

#13: 30-35 mpg if on the flats and sane speeds (<65 mph).

joshhol · #11 03-26-2003, 09:14 PM

Vicki, I got these specs off the plate under the hood on my 76 300D. I hope its the same since it is a five cylinder. OM617 your engine is OM616.
Valves Cold: Water Temp Below 30*C/86*F
Intake .10mm/ .004in
Exhaust .30mm / .012in

Valves Warm: Water temp above 45*C / 113*F
Intake .15mm / .006in
Exhaust .35mm / .014in

Valves cold seems to be the way most people do it. Let the car sit over night.
You should have no problem keeping intake and exhaust seperate as you can see whether the lobe corresponds to the intake or exhaust manifold.

Josh

JimSmith · #12 03-27-2003, 01:39 AM

Vicki,

Unless the fog lights are aftermarket and have their own switch, they will work by pulling the main light switch out one notch with the switch in either the parking light position (one click clockwise) or in the driving light position (two clicks clockwise). In the off position the fog lights will not turn on by pulling the switch out, and it won't stay out when you let it go.

On my 1975 240D the vacuum pump has a line that goes to the brake booster that I believe starts as metal tube and then transitions to a nylon or other synthetic material on its way to the brake booster. There is another "exhaust" line that sends whatever is pumped by the vacuum pump to the intake manifold. This line is a transluscent white when new, and if it is dark on the inside it is because the vacuum pump diaphragm is leaking engine oil, and this is being pumped into the intake. At idle there is a slight intake manifold vacuum on these cars and it will suck oil through the diaphragm leak, making a white smoke come out of the tailpipe. If the diaphragm ruptures, big oil flow occurs and the engine will seem happy to make huge, thick clouds of white smoke.

The vacuum pump is not belt driven. It looks like a small dome on the driver's side of the front of the engine, attached to the block. You will see the line to the brake booster, just trace it back.

Good luck with the car, I really enjoyed mine and remember the horror when I discovered it was dying of body cancer. Jim

william rogers · #13 03-27-2003, 01:52 AM

I pulled the instrument panel out of both my 74 240 D an my 81 SD and wired around the dimmeras both were bad, it is just about perfect brightness done this way...........
William Rogers..........