New owner! 1987 300D - PeachParts Mercedes-Benz Forum

BLACKCDI · #1 10-19-2008, 10:14 PM

I also own 2005 E320 CDI but today I picked up 1987 300D with around 200k miles for $2000 as my commuter car in Bay Area, CA
The paint is rough but interior is close to perfect. All electrics work, including sun roof. Engine never overheats 80-90c in all conditions, even while climbing a very steep hill. Tranny shifts smooth.
Suspension needs work, the steering wheel does not stay straight after the turns on the highway(tie rods?) Seems to be down on power when cold, but is OK after worm up. Ac works but the center vents don't. There is a oil leak in the front of the engine.
Questions, is there only 2 speed adjustments for AC? And how do you turn it off, no snow flake button?
Is there a way to make the engine more quiet? (I got spoiled with the CDI i guess..)
The last thing, I occasionally smell diesel exhaust inside the car while driving, is this normal?
Thanks!

a2t · #2 10-19-2008, 10:24 PM

Nice ride, surprising all the electics are working!

The climate control box should be able to turn off completely by pressing the O button. Mine doesnt for some reason so it stays on all the time. Oh well...

There are 2 manual fan speeds (too slow, and too fast), but the auto button in the middle is nice because it will infinitely vary the fan speed to meet temp wheel setting. Its actually really nice (when working). But Ive relagated to using either low or high speed fan as the system is a bit slow to adjust - or Im just impatient!

Is the sound dampener mat still installed on underside of hood? That makes a big difference, mine fell off and Ive yet to replace it.

Oil leaks - yeah get used to it. Try and clean it and let us know from where its coming. I seem to spring a new leak every few weeks, and it comes from variety of locations. Last was the oil pressure sender housing. After a while you will know by looking at where the drip spots are whats leaking. All part of fun!

Have the tie rod ends checked out, that sounds like most important issue. The suspension on that car is ridiculous, and very costly to repair - especially the over designed 6 link rear axle.

BLACKCDI · #3 10-19-2008, 11:12 PM

Thanks!
I really take pride in working on my cars starting from my BMW 850i to the E320 CDI and I will treat 300D no differently

I will be making a list of parts to order, so I will be posting lots of pics of problematic areas. This forum looks very informative and friendly, reminds me of roadfly E31 forum i use to belong to till I sold the car.
For starters, I heard several opinions about keeping or deleting the EGR valve

should I just buy a new one since it looks original or get rid of it?
I will be using Elf synthetic engine oil, works great with my CDI. What viscosity is preferred?
Thanks guys!

Jeremy5848 · #4 10-19-2008, 11:42 PM

You can bypass/remove the EGR valve or simply plug the vacuum line – Brian Carlton has a nice kit for that purpose. My 87 and 96 cars are about the same as regards noise – inside, you can hear the engine only at idle and low speed. After having a 123, I think the 124 is very quiet – it's all what you're used to, I suppose. The belly pans are important as regards noise as well as proper air flow for cooling. I didn't notice any noise difference after I installed the hood pad. You should not be able to smell diesel exhaust inside, check for exhaust system leaks – might also be responsible for the noise level.

BLACKCDI · #5 10-20-2008, 12:01 AM

Quote:

Originally Posted by Jeremy5848

You can bypass/remove the EGR valve or simply plug the vacuum line – Brian Carlton has a nice kit for that purpose. My 87 and 96 cars are about the same as regards noise – inside, you can hear the engine only at idle and low speed. After having a 123, I think the 124 is very quiet – it's all what you're used to, I suppose. The belly pans are important as regards noise as well as proper air flow for cooling. I didn't notice any noise difference after I installed the hood pad. You should not be able to smell diesel exhaust inside, check for exhaust system leaks – might also be responsible for the noise level.

Thanks,
What does removing the EGR valve do exactly? Sorry i am just trying to learn...
Does not look like I have any belly pans, dealer item or can I get them cheaper somewhere else?
Is there an easy way to check for exhaust leaks?

babymog · #6 10-20-2008, 11:30 AM

Belly pans are nearly impossible to find used, and very expensive new. Worth it IMO, at least the front one under the engine.

Oil leaks are not necessarily a part of the car, none of my '87s have had persistant oil leaks.

I agree, the engine noise should be noticable at high-power settings, idle, and slightly at freeway speeds. If it is louder than just a faint background noise, you might have an engine mount problem (alighment or bad mounts) or other issues.

2.5Turbo · #7 10-20-2008, 11:43 AM

A/C is turned off by engaging the "EC" button on the ACC. It behaves the same as the center button, except the A/C compressor never engages. I always leave it on EC unless the windows are fogging up or I need A/C.

Almost everyone on here will tell you to remove the EGR. Removing it prevents your intake from getting sludged up with soot+blowby oil. Also, would you like breathing your own exhaust?

The belly pan helps direct cooling air somewhat, but its primary purpose is sound deadening. You'll probably be able to get one through the parts section of this site at a better price than the dealer.

babymog · #8 10-20-2008, 12:21 PM

Better cooling, better temperature control.

When the 124 diesel was introduced to the US, I was talking to a Mercedes Engineer on the project, at an SAE conference, ... I was told that part of the efficiency of the 603 engine in these cars is keeping the temperature of the engine compartment warmer in cold climates, thus the thermostatically controlled doors on the driver's side. They are also for sound, and airflow, I would prefer to not be without them.

BLACKCDI · #9 10-20-2008, 12:21 PM

Quote:

Originally Posted by 2.5Turbo

A/C is turned off by engaging the "EC" button on the ACC. It behaves the same as the center button, except the A/C compressor never engages. I always leave it on EC unless the windows are fogging up or I need A/C.

Almost everyone on here will tell you to remove the EGR. Removing it prevents your intake from getting sludged up with soot+blowby oil. Also, would you like breathing your own exhaust?

The belly pan helps direct cooling air somewhat, but its primary purpose is sound deadening. You'll probably be able to get one through the parts section of this site at a better price than the dealer.

Thanks!
What was the EGR valve's original purpose?
And you you think ocassional the exaust smell inside the car can be contributed to EGR valve? How does removing EGR valve affect MPG? +/-?

BLACKCDI · #10 10-20-2008, 12:24 PM

Quote:

Originally Posted by babymog

Better cooling, better temperature control.

When the 124 diesel was introduced to the US, I was talking to a Mercedes Engineer on the project, at an SAE conference, ... I was told that part of the efficiency of the 603 engine in these cars is keeping the temperature of the engine compartment warmer in cold climates, thus the thermostatically controlled doors on the driver's side. They are also for sound, and airflow, I would prefer to not be without them.

Looked around on the web and this site for belly pans without any luck(any tips), how much are they from the dealer?
Why do some idiot mechanics throw them away is beyond me

Bcollia · #11 10-20-2008, 12:29 PM

Welcome to the club!

The only way to make your 300D as quiet as your CDI is to turn it off

BLACKCDI · #12 10-20-2008, 12:45 PM

Quote:

Originally Posted by Bcollia

Welcome to the club!

The only way to make your 300D as quiet as your CDI is to turn it off

I thought so!

Jeremy5848 · #13 10-20-2008, 12:58 PM

As babymog says, belly pans are hard to come by. The dealer will have them for several hundred apiece, I bet (having had to buy one for my W210 car). If your dealer offers a discount to MBCA members (usually 15%), you could pay for most of a year's membership in the savings on just the two belly pans for your car. (Be grateful – the W210 diesels have three belly pans – "noise capsules," the dealer calls them.)

The EGR valve is a smog device and allows part of the exhaust gas to enter the intake. This lowers the percentage of oxygen and makes the engine run a little cooler, thus reducing oxides of nitrogen. In a gasser, this is tolerable. In a diesel, the soot in the exhaust is combined with oil vapor from the turbo and from the crankcase breather for form a black crud that coats the inside of the intake and, in extreme cases, clogs it up. The solution is to completely disassemble and clean the intake annually. A better solution is to block off or remove the EGR valve. Since California does not inspect diesels, the legal risk is minimal. (Besides, it was that way when you bought it, right?)

Jeremy

David Wilson · #14 10-20-2008, 01:22 PM

Quote:

Originally Posted by BLACKCDI

Looked around on the web and this site for belly pans without any luck(any tips), how much are they from the dealer?
Why do some idiot mechanics throw them away is beyond me

I was quoted from the dealer last week, $375 for the front pan. WOW!!
And all I needed was new foam absorbent material. Not available by itself.

BLACKCDI · #15 10-20-2008, 01:29 PM

Quote:

Originally Posted by Jeremy5848

As babymog says, belly pans are hard to come by. The dealer will have them for several hundred apiece, I bet (having had to buy one for my W210 car). If your dealer offers a discount to MBCA members (usually 15%), you could pay for most of a year's membership in the savings on just the two belly pans for your car. (Be grateful – the W210 diesels have three belly pans – "noise capsules," the dealer calls them.)

The EGR valve is a smog device and allows part of the exhaust gas to enter the intake. This lowers the percentage of oxygen and makes the engine run a little cooler, thus reducing oxides of nitrogen. In a gasser, this is tolerable. In a diesel, the soot in the exhaust is combined with oil vapor from the turbo and from the crankcase breather for form a black crud that coats the inside of the intake and, in extreme cases, clogs it up. The solution is to completely disassemble and clean the intake annually. A better solution is to block off or remove the EGR valve. Since California does not inspect diesels, the legal risk is minimal. (Besides, it was that way when you bought it, right?)

Jeremy

Awesome, thanks for explanation! Does Brian still offer the EGR blocking kit? I have some oil leakage from the top of the intake manifold(at the gasket) I should remove the intake and clean it i take it?