Mercedes 300D Suggestions

shiftsok

I just looked at a 82 300cd that did that same jump in revs between shifts. he said it always did that and it hasn't gotten worse. I was thinking about buying the car but the shift revs make me nervous about tranny$$$

shiftsok

thinking about buying an 82 300cd and the owner told me that the boot over the rear cv joint is torn and may have been removed. Is this a problem? I know with FWD vehicles sand and grit can do bad things and I imagine they can get into rear ones even more easily. But the owner seemed unphaxed even as he told me what a bear it is to replace them...ideas?? :confuse:

Mr_Shiftright

Is it a problem? Is breaking a rear axle at 60 mph a problem?

It's not a "bear" to replace. What is a "bear" is paying for a new one. Figure $250 per side for rebuilts (I don't want to know what a brand new one costs) plus 3 hours labor. You could try a wrecking yard but be careful, there are two types of axles and then don't interchange.

shiftsok

would there be any warning before it failed? I know fronts start clicking on FWD cars. The guy who is selling it seems to think it is ok and has been this way for 6 months (uncovered). Could he repack it with grease and recover it or is the grit already in there and the damage done?
thanks!

shiftsok

do the revs between the auto tranny catching mean the tranny is on its way out? is it an adjustment thing? a vacuum thing? is this common? I saw it on a car I was looking at...what would be the order of things to try. I did not try shifting manually on the automatic. If this works does it help diagnose it?

Mr_Shiftright

Yes the CV joint will knock on a hard turn, just like a front one. I see no reason to destroy it on purpose though...you could take the axle off and replace the boot.

"soft" shifting on that Benz transmission is not a good sign. Usually they are neck-snappers. You could service the trans with new oil and filter and see what happens, and at the same time drop the trans oil pan and see what's at the bottom of it. Lots of grit, shiny brass, black goo---you've got a problem. But clean pan, bright red fluid, you're okay and a service might help shifting.

I'm not sure of the effect of a vacuum modulator on the shifts themselves...I always thought the modulator helps to "time" the shift and if it failed you wouldn't shift at all, or at a very high rpm. You can prove this by disconnecting it. But whether the modulator can cause slippage---I kinda doubt it.

texases

Whether or not it's ok, I'd be worried about the maintenance this guy gave the car. No way is it ok to run a CV without the boot, especially for 6 mos.

shiftsok

so is that 250 a side and 1.5 hours labor for just the right side? can re-packing it with grease help (what kind) and the covering it with some plastic or rubber??

ryan77300d

I've changed out my transmission fluid on my '77 300D (it only took 2 quarts, but that's all I drained from it) and swapped the filter.

The other day, it took a while to almost "build-pressure" to go into reverse. This has only happened once, and not since.

Could over-filling the transmission by about 1/2 quart (maxium I could have over filled it by) have any adverse effects? Over-tightened the filter? Anything?

The trans pan was spotless.

Thanks

-Ryan

myblackcloud

hello
this is my first post.
i have a 300D 1982 Turbodiesel. i have owned the car for about 6 years. i absolutely love it. the last time i had anyone look at it they said the fuel pump may be on its way out but to wait til it goes to do the repairs....

right now the problem i am having is some kind of wheezing sound -increases with acceleration but does not seem to affect the performance of the engine.
do you know what this is. i love working on cars but dont know how to diagnose things. i am driving another car right now so if i need to take it apart i could but dont know where to start.

aside from that. what additives do you suggest using. the guy i bought it from said that he put that marvel mystery oil in it every month but i havent been doing that...should i. i guess my thought has been to not do something rather than to do something wrong.....

thanks in advance. i have browsed over some of these posts and respect your knowledge.

Mr_Shiftright

No you'll have to at least pull the axle and replace the boot after cleaning and inspecting the CV joint. Yes, $250 + labor is per side. That's just ballpark, you can shop around. Sometimes wrecking yards will install parts for you cheaper but then CV joints from wrecking yards are a crap shoot because you cannot judge a CV joint by wiggling it around.

Mr_Shiftright

Redline makes a good fuel conditioner for the diesel fuel. I don't think any engine oil additive is worth putting in if you are using high quality oil. Waste of money there...but fuel conditioner is definitely a good idea. Also you have to periodically change out your glowplugs, and your injectors have about a 100K service life.

As for your injection pump, that's going to cost a lot of money to repair. I hope you are prepared for that, if that indeed is a problem on your car. Why does your mechanic think it's "going out"?

I have no idea about your noise, sorry.

mb300dguy

bought this car about 7 months ago, it's a 1984 300D European (Yes, it's gray market.. most things are written in german, it has a top-front filling radiator, and the three-dial system for the A/C. The car was apparently non-turbo when produced in Germany, but a turbocharger (and transmission) were later added. I checked, and sure enough, there was the old turbo.

Just to let you know, I've got this same model/make/euro w/ manual. It's really hard to move the shifter itself and hisses as well when shifting. There is a russian mercedes benz club online that has a decent euro mb serial lookup, gave me some pretty specific info on mine-though I'd really like to have a full manual..Let me know if you resolved your issues and how.

waxuras

My 300d runs great on the open road but when I come to a stop it idols very rough. I have replaced the fuel filter...any ideas?

Mr_Shiftright

when's the last time you put in new injectors? They do wear out you know, about once every 100,000 miles.

So for starters, ADJUST the valves

then add a strong injector cleaner into the fuel

If none of that works, check for vacuum leaks

If none of that works, you may have to go for new injectors. That should give you a smoother idle AND a quieter engine.

Bad injectors also create a condition call "nailing", which makes for a louder than normal engine at idle.

zadams

air filter definitely. then valve clearance adjustment. this will most likely be it. write back if you need instructions for DIY.

zak adams
1985 300d
veg oil converted
185,000
5,000 on veg oil

timingchain

Hi,
My '82 300SD (130,000mi) clunks (sounds like the driver's front) after I turn the steering wheel; it seems something heavy is shifting. I replaced the 'braking support ball joints' almost a year ago, and had an alignment after that. I was told that the ball joints were in good shape then. The noise does seem like a worn ball joint noise, though. Is there anything else I could check?
Also, I mistakenly jacked up the car by the engine/tranny and decided that was definately a bad idea after seeing far too much of an engine shock absorber shaft (I had no idea that was there). Could I have damaged that and would it be making a noise?
Thanks so much for the knowledgeable advice.

Mr_Shiftright

Yes it very well could be the steering shock.

Also sometimes the alignment shims can fall out. If the clunk coincided with your wheel alignment, I'd be suspicious.

Other causes might be a worn pittman arm (the arm that comes off the steering box and connects to your tie rods---and the tie rods connected to the....pittman arm...and the pittman arm connected to the.....oh, sorry.... )

timingchain

The clunk did not coincide with the alignment, it began some time after and things feel pretty tight as far as rocking the wheel side to side etc. when I have the car jacked up. Although I won't rule that out as a possibility.
So what is the deal with the part that I called an engine shock absorber and you called the steering shock? What does it do and how do I test it?
And thanks for the prompt reply.

Mr_Shiftright

The steering shock looks like a shock absorber and it attached to the steering rods. It absorbs shock from bumps and prevents "bump steer".

The engine shock is, as I dimly recall, attached to the engine near the pre-filter on the driver's side.

then of course we have the shock absorbers at the wheels, and then the hydro-pneumatic compensator.

Gee, with all these shocks and springs and compensators, why do the 300Ds still vibrate so much :mad:

Anyway, a clunk in the steering that doesn't occur when you hit a bump, but rather just turn the wheel, suggests looseness in a MOVING assembly rather than a stationary one.

timingchain

OK, I've taken the car out for a more critical test drive, and I would describe the sound as more of a creak than I clunk. It predictably creaks when doing slow, tight S curves, or if I am stationary with the car in Drive and my foot on the brake and turn the wheel all the way (minus maxing out the steering pump) and briefly let off of the brake, then turn the wheel all the way to the other side and let off the brake.
Since I do not need to involve up and down motion, that does seem to eliminate 'bump steer' issues, although rough road conditions do seem to worsen the noise. I tried looking under the chassis while a friend turned the wheel, but although I could certainly hear something, I couldn't see anything moving around that would correspond to it. Do you have any suggestions as to what to look for?

Mr_Shiftright

Heavy groans/creaks could be loose ball joints or A-frame bushings. You might get a long metal rod (solid) like re-bar and have someone move the steering wheel while you hold one end of the rod to your ear and place it on various parts I mentioned.

Or on a lift where the wheels are left hanging....

slugworth

Here's the scenario:
I have a 1983 300D Turbo. A few weeks ago I got to my car and my steering wheel was locked and I was unable to turn the key. I did all the standard jiggling and turning for almost an hour and nothing worked. Universal opinion was that the tumbler needed to be replaced. I understood that getting this fixed would cost me a fortune since I couldn't unlock the tumbler. Luckily, the genius AAA guy came and hit the back of the key with the palm of his hand while turning it with the other and it worked! Great technique that no one had mentioned to me online or off.
Anyway, since the tumbler was unlocked I got the new tumbler and replaced it. VERY SIMPLE. After replacing it I tested it by locking the steering wheel and unlocking it several times.
Unfortunately, it locked up again a few days later. I have been careful to turn my wheels all the way to the right or left so I don't get locked up again but I want to fix this. I still use the palm of the hand technique when I need to.
Now - anyone know if this sounds like a switch problem, a housing problem, or installation error. One thing I notice is that the hole where you put the pin in to release the tumbler does not line up with the marks on the housing - should it?
Thanks.

mdyoung1

82 MERC CD 5 CYL. I DO NOT HAVE AN OWNERS MANUAL AND I CANT FIGURE OUT THE HEAT AND AC CONTROLS. MY CONTROL PANEL IS AS FOLLOWS LEFT TO RIGHT. TEMP WHEEL-DEF-BUTTON WITH SOLID ARROW UP AND DOWN-BUTTON WITH SOLID ARROW DOWN AND OPEN ARROW UP- BUTTON WITH SOLID ARROW DOWN AND EC IN CENTER AND OPEN ARROW UP-OFF BUTTON-FAN BUTTONS ONE ON TOP IS SOLID AND ONE ON BOTTOM IS OPEN AND BAR IN MIDDLE SAYS AUTOCOM. ANY HELP AS TO WHAT CONTROLS WHAT BESIDES THE OBVIOUS DEF AND OFF WOULD BE GREATLY APPRECIATED

mdyoung1

ALSO HAVE A CRACKED DASH IN MY 82. ANY SUGGESTIONS? REST OF INTERIOR IS PRETTY GOOD. HAVE HEARD OF MOULDED DASH COVERS. ARE THEY ANY GOOD? THOUGHTS?

fintail

I think I understand what you are asking...

Solid arrow up and down is air blowing from both the top of dash and onto the floor.

Solid down and open up is floor only, solid up and open down is top of dash/windshield only.

EC = economy, AC not activated. This turns off the automatic climate control and allows only heat and vent.

mdyoung1

IS IT ALL CONTROLLED THROUGH VACUMN? EVEN TEMP CONTROL? I HAVE NO COLD AIR WHICH I ASSUME IS LACK OF REFRIDGERENT OR MAYBE ANOTHE RPROBLEM. I ONLY GET GOOD HOT AIR IN WINTER IF I CUT CAR OFF AND RESTART. THEN AIR IS WARM FOR AWHILE. ANY IDEAS ON THAT?

fintail

Yeah, there's a lot of vacuum crap involved. I had a W126 with what I believe is a similar system. It would sometimes put out warm air even if everything was switched off, other times the heater was not quick to respond. The AC always worked well enough, but the previous owner did have it serviced. These systems have a rep for being troublesome, it could be a dozen things I am sure.

Mr_Shiftright

Probably needs everything. The AC systems in these cars is really pretty sub-standard and rather troublesome. I'd say at the very least a new control module and a major AC service, for openers.

brillanze

I am looking at a 2001 E 320 and considering trading my 1983 300SD. Any thoughts or cautions?

Mr_Shiftright

Well don't "trade" your SD...sell it privately and use words like "biodiesel" and "will run for a million miles" and jump on the current popularity bandwagon for this car before the new diesels come into the country and sink this market. Now's a good time to sell an old diesel, won't ever be a better time.

But a dealer won't give you diddley in trade for it.

As for the E320, you know the drill. Run a CARFAX, have the car thoroughly inspected, and ask for a print out of service records, if they will do that for you. You need to know where this car came from in other words...its resume, so to speak.

fintail

Yeah don't trade the old one, sell it yourself...people are nutty about diesels right now, and you'll double your money with no problem.

About the E320...W210s have a lot that can go wrong. Check to make sure the blower works, check for AC issues, make sure the tranny has been serviced every 50K or so, check for undercarriage rust, have the spring perches inspected, and make sure all electrics work. Also, if it is a nice low mileage car, you might be able to get a good aftermarket warranty for it...this is one of the cars where a warranty is not a bad idea.

dpotter1

i have a 77 and a 79 mercedes that i would like to part out
if there are any parts yopu need off of either of these vehicles email me at the_duke_potter@hotmail.com.
thanks

mdyoung1

LOOKING AT A 90 MERCEDES 300 CE. 116K MILES. LOOKS PRETTY GOOD. IS THERE ANYTHING SPECIFIC I NEED TO LOOK OUT?

lwoolard

I just purchased my 2nd 300d,the first was a 1981, this is a 1983. Couple of quick questions. It idles very rough and smokes white smoke, not alot but some. It quits smoking after it warms up, it also idles better then. I changed both the fuel filters, no better. Also the tach doesnt work. I unplugged the black thing on the fender well and cleaned it. No good still doesnt work. Any suggestions?

fintail

Depends on the price. You'll want records. The (M103) engine is very durable, but if not maintained can get a little clattery and smoky, expensive to fix. Make sure the transmission has been serviced. Make sure the electrics and locks work. These cars can rust at the wheelarches and back window especially. Good shocks make a world of difference, make sure suspension is good as well.

brakeengr

you may want to try the diesel purge- the real thing (not added in the tank- but hooked up directly to go into the injectors). I did 2 cans in my 82 300d, and thought it made a difference. You can buy the stuff off ebay.

Mr_Shiftright

Many diesel owners are unaware that diesel injectors wear out just like other parts, and if yours haven't been changed for 100K miles, this is a likely suspect---if the engine does not respond to filters, purging and a good valve adjustment.

lwoolard

Thanks, Im going to adjust the valves tomorrow. It has already had a diesel purge. Any suggestions about the tachometer, also the cruise control will not engage.

Mr_Shiftright

Cruise control is probably the amplifier, which is behind the radio. It is a common cause of this failure. Of course, check the fuse. I think rebuilt amplifiers are about $100. Some people claim you can take 'em out and hit all the soldering joints with an iron and that it will work again. Worth a shot I guess.

The tach? Another common problem. Try to trace the wire going to the tachometer drive (I hope I'm not mixing up my MB models) and see if it's loose at the tach drive.

lwoolard

OK adjusted the valves about an hour ago. Did not help much. Is there a way a do-it-yourselfer can check the injectors? Where is the tach drive at? The engine runs much better when it is warmed up but there is still a miss in it. Is there a way to adjust the idle on it?

Mr_Shiftright

No you can't really check the injectors unless you hook them up to a machine. You can do a compression test though, if you have the correct gauge (don't use a regular compression tester)

lwoolard

ok Is there a way to adjust the idle if you give it a little more fuel it seems to run alot smoother. :confuse:

Mr_Shiftright

I guess you could adjust the air flap but I don't remember how to do that, sorry. Worn injectors give you a very erratic spray pattern. There's no way to adjust the amount of fuel you get at idle. The pump does all that I think. You can adjust pump timing but that's pretty tricky.

ryan77300d

There's an idle knob right below the oil/temp/fuel gauges, turn it all the way left to the stop. This would be the max setting. From what I've found, is that if you drive with it maxed all the time, the transmission downshifts harder, and stopping distance is noticably increased, but the whole car doesn't convulse when you're at a stoplight with your foot on the brake. With the knob turned all the way right, everything's smoother, with the sacrifice of a shakey car at a stop.

But that's on MY car, and I know my injectors are dirty, so the shaking my not be a result of the idle setting.

As for white smoke, is that not water being introduced into the cylinders? And the fact that it goes away right after warming up is a little scary.

Mr_Shiftright

Ah yes, the old idle knob. Forgot about that.

As for the rough running, white smoke, etc.---that's why I recommend a compression test.

lwoolard

The car is not losing any water and is not running hot so I don't think that there is water in the cylinders. The guy I bought it from had just done a diesel purge. He suggested that the injection timing could need setting. The idle on it does seem mighty low. I don't have the old idle knob on this one, had it on my 1981 but not on this one. Am I hurting the car by driving it in this condition?

lwoolard

Well, I found the idle adjustment. It is a screw with a locknut between the injector pump and the engine, very simple to adjust. That helped my problem tramendlessly. However it still smokes and misses when it is cold. After warm-up it know runs smooth. There is a clangy vibration separate from the normal engine noise that comes and goes. It sounds like it is coming from the side of the engine where the injector pump is. Any idea what that may be?

Mr_Shiftright

Could be what they call "nailing", which is engine noise created by bad injectors or a badly timed injection pump.

lwoolard

How hard is it to set the injector timing? Can I do that myself? Should I just get new injectors if so are they hard to install?