Hi guys. Bought an awesome SEC 380 (1993) in ultra extreme condition full option (more than full, a lot of useless to-much-options). Nowhere you would get such a perfect running beautiful SEC. Accident free. no damages around the car. Just Wow



ok ok to the point: Now I have some small things that are really concerning me:

_____________________________

Oil pressure. The Oilpressure Meter in the beginning (cold start) is at full = 3 Bar the RPM raises to 10.000 then normally 5000 in idle.

When the temperature reaches nearly more than 40°C the RPM lows down to 5000 as usual. Till now everything fine.

When in idle mod again the Oil pressure meter shows me that the pressure is going down and down the hotter the engine is getting okay I THINK thats normal. Then when Mercedes optimum temperature of 80°C is reached the pressure is around 1,5. Is that normal?

Okay if yes, is it normal that the oilpressure is starting to jump very fast up and down between 1 and 1,8 in idle mod? When I am stopping at a traffic lamp and watching the display it does not look normal and the car has also some vibrations which can be conntected to the oil pressure, because the rythm is the same. But RPM is absoultely stable.

But in cold start it is perfekt I can not hear the engine and no vibration at all. I have to look at the RPM if the engine is still on.

_______________________________
Leather Seats, The Leather is in absolutely perfect conditions, but on some places, mostly on the driver seat the blue color is fading. But the leather is not porous. Because under this dark blue color the original leather color is coming out. (brown)



now the question, someone told me I have to demount the seats and recolor them with the same MB Leather color and everything would be fine.
Is that right? If yes, where I get this spray etc.

_________________________________
When I put on the Aircondition as usual here in Dubai (24h) the temperature of the car raises up to constant 95°C. but the extra cooler fan still does not turn on. I think thats normal because it is not going more than 95°C. I looked at my friends VW, he has only constant 90°C wether the A/C is on or not.

_________________________________
Gear, simple: What does S and L means in the automatic shift gear? I know when I put L the car drives in the 1st gear. but what is S, it has no effects.


Thanks guys. I know its to much. Sorry for my bad english. I am just a German

 

Change oil and filter use a good name brand oil 20W-50.
The oil pressure must be at top limit #3 @ 1200 RPM

 

always at 3 BAR? :-S Does not sound plausible

 

No not always, just at 1200 rpm it should be at least #3
At idle it could be at #1 but as you raise the RPM the pressure should climb by the time you reach 1200 RPM the oil pressure should be #3
It is important to change your oil and filter first, 8 quarts, make sure the oil level is correct on dip stick,

 

Everything sounds fine, use Mobil1 15w-50 and your engine will last forever.

 

1 bar is 14.5 psi and this should be normal pressure around idle warm. The "normal psi is 1 psi for each 1000 rpm". So 50 psi would be considered normal for a "typical" engine.

Your engine has 1 bar..14.5 psi at idle. Then if I understand right 3 bar at normal driving which is 42.5 psi. These pressures at normal 80C which is 176F would be good pressures.

Now for the variation. This shoulds like a bad sending unit assuming it is an electric gauge and not a direct liquid gauge. I think you are ok with the engine, but the gauge sending unit might need replacing if it is electric. Sounds like a very nice car. I would just bring all the service up to Merceds standards if they aren't there now and drive on. Jim

 

Jim, I have difficulties to understand your sentence. Kindly describe it in easier english, as you would describe it to some child.

And thanks a lot guys. But what about the other issues, come on, read them please.

 

ppl. Nobody can help me with the other issues?

 

Gauge sending unit = some device mounted on your car's engine/block sending measurements (RPM, Oil Pressure, Engine Temp, Oil Temp ... etc ).

Electric gauge = uses electricity for measurement.

Direct liquid gauge = directly measure with some mechanical/physical means.
.

For the AC i think it is normal, maybe you should flush the coolant and replace it .

From experience wether you choose S or L or D the car will always start in 2nd gear .

Here you have some tech info...
Download Link: http://www.filesend.net/download.php...05410ce675333a

i was in dubai for a 5 month period for work, did not like it .

A Mercedes-Benz is like an antique , it only gets better with age.

 

[QUOTE=vibra;2108728]
Gauge sending unit = some device mounted on your car's engine/block sending measurements (RPM, Oil Pressure, Engine Temp, Oil Temp ... etc ).

Electric gauge = uses electricity for measurement.

Direct liquid gauge = directly measure with some mechanical/physical means.

[QUOTE]

The electric gauge has a variable resistor that changes resistance to control the voltage to the dash gauge. This is what gives you the reading. When the resistor wears the voltage will move very unpredictable and cause your gauge to not repeat correctly. Replacing the electrical sending unit will sometimes solve these problems. hope this helps


When the temperature reaches nearly more than 40°C the RPM lows down to 5000 as usual.
This sounds like the cold enrichment is just increasing rpm until the engine warms up to prevent emissions. My E500 has a similar start up rpm increaase.

The cooling fan. I assume you are talking about on the radiator. If they are electric they are temperature controlled. I have a car with electric fans that won't come on until 108 C. Without the service manual I would say you have 2 fans and one comes on to control temperature until a high limit is exceeded then the second will come on. Pictures of the fans would confirm this. Jim