Mercedes 300D Suggestions

fintail

I use a petroleum-based metal cleaner called "Nevr-Dull" on the fintail, it also works at removing residue from glass and paint. Maybe it would work on the dash pad with some firm rubbing. It might discolor it though.

slugworth

Have you tried lighter fluid? My friend has a record store and uses it to get sticker residue off of album covers and it works without damaging them. Never used it on a dash but I would try it. On an inconspicuous part of the dash, that is.

Mr_Shiftright

3M makes a glue remover. I think they call glue removers "releases".

But again, I have no idea what this does to dyed materials.

bb975d

I recently was given a 1985 300d. my grandfather bought it brand new in 1985 and garaged it its whole life. it only has 100,000 miles. there are a few probs with it that I need help with. First off- The ac compressor is toast and I am working on replacing it. the prob I have with the climate control is that it keeps blowing the fuse for it. typically when slowing down after driving on the freeway for a while. when it is working sometimes the heat is hot and some times mediocre. I have a few vaccum issues with the car also which ill get to too. Im just trying to start with the most important problems9 for me at least) first. any suggestions? thanks matt

bb975d

btw its a turbo deisel

matty4

Hi, I have an 88 300d turbo with 240k that runs like a charm. Just have a few questions: the car leaks when it rains. it leaks down through the hood on the left side and drips from above the foot pedal for the e-brake (which unfortunately is completely loose). But more importantly, i think water may be coming in through the sunroof and draining down through the panels onto the floor because I get puddles in the rear foor bays (notably the left). Also, the diesel lines connecting the cylinders are leaking-- is there any trick to replacing them? I am planning on driving cross country in the car next month. Any tips for ensuring that the engine and car is as less stressed as possible or parts that i may want to keep on hand (electrical??) thank you very much.

matty4

ps. how about adjusting the valves or checking compression? (the car performs quite well) is it worth flushing the brakes and radiator (which hasnt been done for at least 20k). what about transmission service? Also the cruise control doesnt work... if i try to engage it, it just keeps accelerating. Spare battery just in case?... spare fuses?

Mr_Shiftright

Yes you can check the sunroof drains pretty easily and also check for a leak through the tail light lens gaskets (you can put newspaper in the trunk and test it with a garden hose or pitcher of water---ditto the sun roof drains.

The drip under the driver's left foot might be the windshield gasket--original windshields have the Benz "signature" on a sticker on the passenger side, replacement windshields don't and sometimes they mess up the gaskets when they replace the windshield...running some LATEX black caulk along the windshield gasket often works--you can work latex easily into the gasket edges, and it's so easy to clean up afterwards---no sticky stuff! don't wet it for at least a day though.

Another possibility for a leak is the fresh air cowl under the windshield. You can lift that up (remove screws, remove wiper arms) and see if the drain in there is plugged up with leaves and debris. Normally you can pour a little water into the fresh air cowl and you should see the water drain out behind the front tire area.

Brake fluid and radiaor flushes are an excellent idea, and so is checking valve adjustment. I don't think a compression test is necessary if the car starts right up when cold.

On any diesel, if you have to crank 'em a lot when they are cold, that's an immediate sign of a problem.

matty4

Thank you for your advice, Mr. shiftright. I'd also like to describe to you my vibration... it only occurs at higher speeds... over 65 mph, and is a slow vibration (frequency wise) that sounds like flying in a small twin plane or cruising in a twin skrew boat with the engines slightly out of sink.

Mr_Shiftright

Vibrations can be a bear to track down in a car. The most likely suspects are always a) rear wheel balance and b) driveshaft (frozen u-joint, or bad support bearing).

matty4

howdy. I am moving to a very cold place in the winter and wanted to know how i can optimize starting and performance in frigid temperatures. Spank you so much. Also, should I worry about the trap oxidizer? ...Is there a way to remove it? (I think its still intact)

matty4

I have a vaccuum problem. To shut off my car, I must simply keep the brake pedal depressed.

matty4

also, my car has been sitting since september. I added a marine diesel engine fuel preserver according to the instructions. Is there anything I should really do before starting or driving the car again?

matty4

mr shiftright, you said earlier "You must never drive these old diesels at sustained high rpm." what can I do when driving across the country to help this?

Mr_Shiftright

Well just keep a sensible speed, 75 mph or below. And use the cruise control, if it still works (doubtful but it might).

Vacuum leaks are common...check under the hood for these first...there are plenty of little "junction" areas for vacuum lines with loose hoses and or cracked plastic junction blocks.

Primary concerns for cold starting are an anti-gel in the fuel and a super strong battery. In severely cold weather, you can add a little gasoline to the fuel, maybe a gallon or so.

wvoplush2

Well, I did this last year--mass to oregon---and back--1/4 the way on veg oil..except mine is 82 300d turbo (w123 chassis)---some of these things MAY apply to you or other readers....

the cruise worked fine, and rarely did i go over 80--usually drafting behind a semi downhill, etc.

test the cruise on the highway---you may notice it pulse when the turn indicator is used....

you will probably spend a lot of time pushing it up...

check your oil every stop....never go below 1/2 qt low if its a leaker... i also use lucas oil stabilizer

make sure that rubber gasket on the oil fill cap is not cracked/damaged/too hardened- otherwise motor kaputt!

get a pre-trip inspection on brakes, steering..

change both fuel filters if u loose power..

join AAA...

if the odo/ speedo starts clicking, use a screwdriver on the front (dont bother removing the whole inst panel) and pop the numbers back to 30k less...clicking stops!! i only did this because i don plan on reselling it...

never prime your engine with more than a squirt of wd40/ starter fluid. in montana, when running the injector pump dry from a plugged veg oil filter, then switching back to diesel--wouldnt start so i primed with wd40. no start...thought more would help, then, all of a sudden, engine went to 6000 rpm. I was lucky-- didnt blow and I made it back to mass, when a month later the brakes went out..

great car otherwise, tough as nails, great cooling system--

enjoy!

ryan77300d

AH! MOTOR KAPUT?

Really? Would a '77 300D have one of these washers? I bought mine without...but I have been losing about a quart of oil per 1700miles.

Would this be normal?

I suspect an oil cooler line's a little loose if not, as it seems to be dripping right under that area.

Any suggestions?

Thanks

-Ryan

Mr_Shiftright

Old diesels burn oil--that's where it's going. You've probably noticed oil in your air filter no doubt? That's blow-by through the piston rings.

A quart every 1700 miles is good compared to most high mileage old 300Ds.

waxuras

My 85 300d was idling a bit rough. So I thought I'd try and change the fuel filter. I forgot to fill the filter back up and started it. It ran for about 20 sec and stopped. I did the prime thing and finally it started. Great...hey and it's running smooth too!

Decided to run to the store in my new smooth ride. Got there and when I came out...it wouldn't start. I've gotten a new battery, and glow plugs. It acts like it wants to start..but hasn't so far...any idea's?

Mr_Shiftright

You blew the glow plug fuse?

brillanze

I have crunch noise when I put my car (1983TD) in reverse. Only in reverse-no drag or other problem when I go forward at any speed. This car has over 300,000mi on it (the odometer broke)--I've driven it like a bat out of hell for almost a year.

Any ideas what this noise could be?? :confuse:

ewvdt

possibly your rear CV joints/axle is the culprit

Mr_Shiftright

Very good possibility. About $250 per side + labor, which isn't very difficult to do. It's a bolt/unbolt job.

waxuras

Thank you I didn't check that. I did a search for the fuse online and couldn't find it. Where is the fuse located?

Mr_Shiftright

It's a big 80 amp metal strip type fuse in the relay box...as I recall, bolted to the left fender area near the radiator. You should be able to trace wires from the glow plugs back to it.

waxuras

After I replaced the glow plugs the indicator light is coming on while starting. Whould it still come on if the fuse was out?

Mr_Shiftright

It should come on and stay on for about 30 seconds. Do you wait until the light goes out before you crank?

waxuras

Yes I do wait for the light to go off before cranking.

I did read a post somewhere that says the light would still come on if the fuse was cracked and not getting the power to the GP's. So I will check that when I get home tonight.

One thing I forgot to mention was that after I got the car running again (after the fuel filter change,) I went to the store. When I tried to start it again the GP indicator light would not come on. And it would not start. So I put in a new battery and Glow plugs. The indicator light is working now but not starting. Maybe it is the fuse? That would be nice. I first thought was I had got air in the injector line.

Mr_Shiftright

You could still have some air in there.

does it start instantly when warm? If not, then it could be a glow plug issue. If it won't start easily when warm, then it might be air in the lines, tight valves or lousy fuel.

All a diesel engine needs is good compression and some clean warm diesel oil...there's not much else involved.

waxuras

Won't start at all! Thanks for the fuse tip. I'll check that first thing this evening.

Will it start if there is air in the system?

Mr_Shiftright

Nope!

waxuras

So if the fuse is OK...It probably is that.

I know about the primer pump...is there anything else I can do?

Mr_Shiftright

Primer pump is a bit anemic when they get old so that might not be enough. You may have to hook up a remote starter and crank it while breaking the fuel lines open at the injectors, until fuel leaks out. Not much chance of fire, don't worry.

brakeengr

I had that problem too when I changed the fuel filter- what helped was to not tighten the spin on filter all the way- leave the top bolt loose, then prime until the diesel flows out under the copper washer- that way you are sure all air is out; then tighten.

waxuras

Remote starter? First I've heard of one of those! I'll check into it. Where should I crack the injectors at the engine?

Mr_Shiftright

Well the idea is to crack them and make sure fuel dribbles out...then you know there is no air.

The remote starter is just a simple device that allows you to crank the engine while you are bending over it.

I suppose you could start at the injector lines at the pump, to make sure there is no air between the pump and the injectors.

brillanze

WHAT little thingy to make the dash lights work????
I'm about to pay a mechanic to pull the dash and replace the lights, but if there is a thingy... let me know

Mr_Shiftright

I think (if I recall correctly) it sticks out of the dash...it looks like the odometer mileage setter....or if that's not it, then it's a little wheel under the dash....I forget...I got all my old cars mixed up right now....

ryan77300d

There is a thingy, rest assured. First, be sure that the park lights or head lights switched on, then turn the poteniometer on the dash, the small black knob sticking out right below the spedometer. There's two, the one you want is the one on the left. Just turn it, don't push it in as that would reset the trip odometer.

If that doesn't work, maybe yours has been long since lost. That was the case with mine, as someone replaced the speedo and lost track of where the petentiometer for the dash lights went. If this is the issue, and since the bulbs make it like reading the gauges by candlelight anyways, simply remove the cluster by pulling and prodding and then splice a wire between the two contacts where the poteniometer should have been. Then, your console, gauge and running lights will all go on when you turn the headlights on.

-Ryan

brillanze

Holy Smoke! There IS a thingy! and it really works! Thank you :shades:

slugworth

I know that this could be a lot of things but its worth a try if it saves me a trip to the mechanic.
I drove an hour and a half to a nearby city and back yesterday and then parked my car for three hours or so. when I got back in it kind of turned over weakly for a few seconds and then stopped. each time I tried to start it again the dash lights would just come on and nothing else would happen.
I just got this car a few months ago and when I checked the battery it was over six years old. so I replaced it. unfortunately, the same thing is happening.
does this sound like a typical MB situation?
its a 1983 300D Turbo.

Mr_Shiftright

Are you saying that even with a brand new battery it wouldn't crank over, or that it cranked over fine but then went dead again a while later?

If the former, check your battery cables and your starter motor; if the latter, check for a strong battery drain and a weak alternator.

Also, if the former--you could have gotten a sleepy battery off the shelf. Diesels need VERY strong batteries to crank over.

slugworth

with a brand new battery it wouldn't crank over. I will check the cables and hope that it isn't my starter.
Thanks.

Mr_Shiftright

Try a jump start. Could be a bad battery. If it kicks right over, take out your battery and have it thoroughly charged up overnight. If your "new" battery will not crank it but a jump start does, then there you go.

If the jump start won't crank it, check your cables for corrosion and bad ground.

If you are careful you can also by-pass your cables entirely with the jumper cables and go directly to the starter...but don't touch any metal with the positive lead, of course.

ewvdt

The negative cable bolts top the body and can get corrosive as was mentioned. When I jumpstart from another battery I make the last connection to the engine away from the battery for safety.

Mr_Shiftright

Very good practice!

Diesels can be tough on starter motors, although I personally never had a problem with one.

The older the diesel, and the more miles it has, the more you need a really strong battery to spin that engine over quickly. Engine compression is, after all, the only thing that a diesel works on...if you have lower than normal compression, you are going to have to crank the engine more times to get it to fire, and sooner or later all that cranking wears out the starter.

A Mercedes diesel in good condition internally should start up immediately, as in LIKE THAT!...if you are cranking before starting, something's not right with it.

ryan77300d

Alright, to continue my dashboard saga, upon closer inpection, I have determined why there are marks on my dash. These dashboards apparently have some sort of "clear" coat finish over top of the base vinyl, or so I'm guessing. What's happened is that the electrical tape pulled off some of this clear coat, and left a shinier base coat (as it's been protected by the clear all these years). The marks aren't on the surface, they're lack of clear.

Is there any hope in fixing something like this? Could I clear coat the dash with some sort of professional vinyl finish?

My plan would be to try and clear coat it with auto paint, and if that fails, scrape all clears off, original and remedial, from the entire dash.

Or I could buy a new glove box door (yes, that's ruined as well) and put a dash cover on it.

Suggestions would be greatly appreciated.

Thanks

-Ryan

76dieselman

Hi everyone I am having a bit of trouble with my 1969 220d. It came as a parts car with another 220d that I bought. It had been sitting in a dry garage for a number of years and hasnt been run in a while. I consider myself a savy mercedes diesel mechanic by bringing back to life a 300d that is a daily driver.

The problem is I just cant get it to start. I've cleaned and ohm tested all the glow plugs and they work. I've cleaned all the grounds on the chasis and block. I've drained out all the old fuel and replaced it with new clean fuel. The injector pump works and the injectors are spraying fuel. I also just did a valve adjustment today(the valves were really off). I has compression because its very hard to turn over the engine by hand when I was adjusting the valves. I even plugged in the block heater to warm up the engine. It cranks over like mad but wont fire.

I am just lost and dont know what else I can do or what could be the problem. Theres 150k on the motor and the entire car is complete except its pretty rust. Any help would be great. If I can't get it going in a few days its gonna become choped up for parts. (near perfect interior)Any help would be great. Thanks

Mr_Shiftright

Hmmm....you may need to do a compression test. Compression is, after all, what makes it run, nothing else really.

You could try spraying some starting ether and also replacing the glow plugs entirely.

slugworth

ok-
I will be replacing my starter on my 1983 300D Turbo. So- would you recommend having a mercedes shop do this work or is this a job that joe mechanic can do down the road? What do you think is a fair price for this job?