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Comments
Old AC systems like on the 300D need recharging once a year at least.
I know here in WA, the parts stores don't carry it anymore but I would guess they could special order it.
You mean you replace the entire black box or just the fuse?
The fuse is just the symptom, not the disease.
My question is about a mercedes 300td 1985. I am going to buy one. I really really want the third row seat. I found a company that sells them. The car I am looking at buying does not have a third row seat. Does anyone see/know a problem with just installing a third row into one that did not origanilly come with one?
1. leak in the rear left passenger foot pan. i dont know where the water is coming in from, it seems to just magically appear there in the floorboard. a decent amount of rain will have it flooded. cheaked the door seals and they seemed fine. the water seems to collect around the plastic barrier for the electronic wiring.
2. difficult starting; i live in texas and the weather here is pretty nutty, it will be cold in the morning but then hot in the afternoon. when its even the slightest bit cold, the car refuses to start. the starter can crank it with good power, it just wont start. sometimes it takes me up to 4 tries to get it to fire, and once it does, it blasts out black smoke, and leaves this big black circle in the driveway. after that, it will be reliable as long as i dont let it cool down for too long. when its hot, however, it very easily turns over, at least as good as anyone else's gas car. i usually let the glow plugs heat for a full minute before trying to fire it. i never crank it any longer than 5-10 seconds at a time. i had the ground battery wire melt in half (well actually my dad did that i dont know exactly what he did, probably cranked it too long. the battery is fairly new, and is clean. in the heat everythings A OK but when it gets cold its a real pain in the butt and kindda embarassing at times.
3.the sunroof sometimes will hesitate when its going back to the closed position. it has no problem going open, but when you close it it has trouble. (sometimes)
4.the back seat's upholestry is messed up on the inside. i have textile vynal, the vynal looks really good, only minor marks and some sun discoloration on the top. the inside is all rotted out though. if the sit in the seat hard enough, little brow flakes blast out of the crack. could i restuff this myself or is this a difficult job? also the seatbelts all need replacing. (including front ones) how easy would be replacing the seatbelts?
5. oil leak. oil leaks out of the bottom of the car, and i cant tell where its coming from. and one newbie question, wheres the oil filter? lol i looked everywhere for it. is it on the bottom because i know many european cars have filters on the bottom. and also, what kind of filter should i get because none of the shops have them apparently.
i love this car its really cool. all my friends like it too they always get me to take them places, even though its not always pretty. its been taken good care of, its at about 142K miles and throughout its lifetime its always had diesel enrichener. its my first car, and i dont know if it was such a great idea to get a classic car for my first and then know nothing about it, but ive been trying really hard to find out about it. i want to keep this car till the engine explodes and the wheels fall off. anyway thanks for reading this and all help is greatly appreciated.
Here's my best advice to start.
Your diesel needs just a few things to start well when cold. Good fuel, good compression, the right oil viscosity for the temperature, good glow plugs, good starter & battery.
Here's what you need to do:
1) Check valve clearances. (They ruin good compression if tight or loose)
2) Injectors can be worn out. (They'll dribble instead of spraying causing smoke, poor starting)
3) Oil viscosity. (Heavy oil in the cold morning slows engine cranking)
4) Glow plugs, if one fails they all stop working, they're in series.
5) Your battery, starter, cables must all be in like new condition.
Lastly. Your oil filter is in a large canister on the left side of the engine near the fire wall, its huge by today's standards and you remove the top lid of the canister to remove the filter element inside. Be sure to change the "O" Ring in the lid each time, it comes with the filter.The filters can be bought at Napa, AutoZone, Advance Auto Parts, and Pep Boys.
Have fun!
Water Leak: Sounds like a plugged sun roof drain, definitely.
Oil Filter: BUY IT FROM THE DEALER!!! Do not use some Mickey Mouse aftermarket filter. It's only $12 from Mercedes and it will fit perfectly. It's a cannister type (drop in filter). Messy nasty ugly job.
Sorry to trouble you with my extream lack of vehicle knowledge
but I have recently been given a 1980 300D for my B-day(built in late 1979), and it was working great for a few days, with the exception of a few times it didnt want to start, (key would turn to 3rd position and the glow light would have cleared but no turnover) but after the 3rd try the car would be fine for a day or so, this evening after parking I had the same "no turnover problem" but after several minutes of trying the glow light stopped showing...this coincedently happened when my friend lifted the hood..(probably just a fluke and not related) and so it sits 4 hours later and no glow light or ingnition sounds?
I REALY enjoy driveing this car alot, and all the style it has, Im in the process of selling a 86 fiero GT to get some $ to invest in this car,
any help would be so greatly apreciated!
thank you for your time!
-Pat
Vacuum controls the fuel shut off switch. You have a vacuum leak somewhere in the car now.
"and so it sits 4 hours later and no glow light or ingnition sounds? "
Are you saying that after 4 hours you get not glow plug light whatsoever and that the starter motor will not spin the engine? Or ????
If you just lost the glow plug light, you probably burned out the 80 amp shunt fuse in the black relay box that is attached to the left inner fender, up front near the radiator. Sounds like you also need new glow plugs, and maybe a valve adjustment.
Diesels fire strictly on glow plugs and engine compression. If you have weak glow plugs or weak engine compression, that will prevent starting. The injection system is near bullet-proof so I don't suspect that.
UPDATE, tried it today and the it started again? but the glow light never came on once??...and it took about 3 starter turnover sounds before it started?..
then I shut it off waited 5 min tried again and the glow light came on ..it was dim and it was flashing?? but it eventualy disapeared and I was able to start again,..
i hope this info helps refine the problem
and thank you so much for the reply! you gave me something to try, I will be replaceing the shunt fuse you spoke of and new glow plugs, hopefully it wont be too expensive...
if you have any other Ideas I realy apreciate the advice
on a side note I know a Mercedes dealer is the place to bring it to, but I live very far from one, but their is a repair shop that advertises it works on exotics and lists Mercedes as a car it works on, would it be adviseable to take it there? or should I plan a treck to the closest Mercedes dealer?
thank you again
-Pat
I have found that a fuel additive, new filters, a strong battery and new glow plugs fix more Mercedes diesels than anything else.
New glow plugs installed might run $150 or more.
Im makeing calls to various shops, can you hurt the car by starting it without glow plugs?
-Pat
You should also check valve adjustment if that hasn't been done.
What are the things I need to get done to get this thing running?
Any pitfalls to look out for?
What sort of a maintanence schedule does this car need?
Should it be taken to a MB dealership or to an independent mechanic?
I have only driven gasoline cars for the last 5 years so no clue about diesels and how they work. All I can say is that the car is in amazing shape...even has the new car smell in it!!!!
Please advise. Thanks.
Yeah, there are some important things.
First of all, the key to success with diesel cars is:
CLEAN FILTERS AND CLEAN OIL AND CLEAN FUEL TANK.
So how do we accomplish this?
First of all, we have to make sure your fuel tank is not full of water and crude. Dumping it all out and cleaning the tank is a big messy job and may not be necessary, but you should put in a "biocide", something that kills algae (yep, they love diesel fuel) and removes water, and a fuel conditioner.
Then drive the car and see if it runs smoothly. If it seems okay, then change the two fuel filters immediately! That should get rid of all the crud you picked up with the cleaners. You may have to do this twice in a row with the filters. They aren't expensive. The main filter is only about $12 and the secondary filter is only about $5.
Once you have the fuel situation under control, then you should change the oil and filter.
If you went to a Mercedes DIESEL specialist, they could get the car in shape for you---you just tell 'em it's been stored for a year and they'll know what to do.
Personally I'd put in a quick $500 for oil change, filter change, fuel tank additives, safety check, tire check, belt and hoses check, and I'd flush out the brake fluid, too...and....do a valve adjustment.
I'd recommend a 3,000 mile service schedule for oil changes. As for filters, etc., you can buy a service booklet at the Mercedes dealer that will tell you everything you need to do---although it sounds like Uncle might still have these books in the glove compartment.
So to summarize:
Once the repair shop has you up and running, resolve yourself to frequently change the oil, pay attention to the fuel filter change interval, and ALWAYS ALWAYS, put in a diesel fuel conditioner when you fill the tank----REDLINE makes a good product.
Clean fuel solves 90% of diesel car problems!
I have a 1978 300D with the electric sunroof, and no manual way to open it. There is no response when I move the switch, and I'm trying to narrow down the problem.
I can't find the location of the roof motor anywhere in the Haynes manual, and it didn't appear to be in front of or behind the track.. Is it inside the roof itself?
Any suggestions?
Last week I bought a 1984 Mercedes 300D Turbo with 198k miles. The car seems that it has not been treated well the last couple years, but the engine runs strong ("the unkillable".) I fixed a couple things already, but I am having problems fixing a shifting problem. The transmission shifting happens as follows, each and every single time no matter the throtle position:
From 1st to 2nd at about 3700 rpm
From 2nd to 3rd at about 5500 rpm
From 3rd to 4rd at about 5500 rpm
I was wondering if there is some sort of vacuum modulator or something similiar of the sort that senses when the transmission should be shifting gears. As of right now it seems that the shift points are at fixed rpm points no matter what I do.
Please help...
Thank you.
Your shifting ranges are determined by a mechanical linkage off the throttleplate attached to the injection pump. It's most likely broken off or disconnected. Shift points are supposed to vary based on throttle position.
I would recomend you buy the Haynes Service Manual #697 for the M/B series 123. It covers all the basic adjustments. It's available at the major auto parts stores.
I have 300d sedan and trany is bed,found used transmission same year from 300td but they couldn't tell me is it same .
thanks
If not, if it's from the front, check your motor mounts and transmission mounts. These diesels can shake a lot and break them and cause driveshaft noises or fan contact, etc.
You aren't going another 250K now be realistic here unless you plan to spend a good deal of money to get there. The odds of that mileage are extremely remote, but 300k-350k is possible if you take really good care of it and don't drive it TOO FAST. These older diesels do NOT like to rev up. Try to stay under 76 mph if you can. Change the oil a lot, adjust the valves every 30K, change your filters often and flush your coolant every two years.
Thanks :shades:
Still, I can't fathom anyone buying a high mileage one. They are a maintenance disaster as they age. Few shops will work on one and parts are very expensive.
Lastly, the crazy price of diesel fuel now.
Fortunately, they are in abundance so one can pick and choose. Generally, if the car is a bit shabby and comes from a cash-poor owner, this is not a good sign.
While the diesel fuel is expensive, if you "brew your own" you can generally keep fuel costs well below service station prices--I've read something like $1.50 a gallon. But if you buy pump diesel or pump B100 your operating costs will be well above a modern gas car.
Besides, for some folks using BD is not about costs, it's also about making a statement, recycling, etc.
Try going down a hill with no power applied, like just just coasting on idle. If the noise continues longer under this condition then it's a real possibility. This is a longshot, since the lower end of these engines are built so strong. With that mileage however, it's a possibility.
If fuse didn,t blown check also the relay
it might located at front fuse box or inside the bagage,
if the relay audibly when you operated the switch it means your motor
is damaged.
After driving other cars, nothing stacked up to the tank-like build quality of my Benz.
I want another diesel, probably a W123.
Is performance improved with the lighter W123?
As far as reliability is concerned, am I better off with a 300D non-turbo, or with constant maintance will the turbodiesel reward me with great reliability?
Also, I love the coupe body. What type of premium should I pay for a 300CD over a regular sedan?
Thank You
Carlos