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S600 C140 1994
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Discussion Starter #1 (Edited)
When the engine is cold the pressure allways lies on 3 during idle.

With warm engine on idle the pressure lies around 1,5 (sometimes just under) and a little higher during winter. The pressure rises to 3 when I start driving.

What should the pressure be on idle and when driving? :bowdown:

I have nothing to compare with and I dont trust the short, guessing answers i get from the local machanics here cause they have no experience from thoses engines. :eek:
 

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SL55, 300SE, GL450, Daytona 955i
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Normal and typical values:
Car cold:
Idle: 2.5-3 bar
drive: 3bar

engine at normal running temp:
idle: 1-1.75 bar
drive: 3 bar

car hot:
idle: 0.5 bar
drive: 2.5 bar

as you can see, no matter what condition and temp, you should never see a combination of engine speed > 2500rpm and oil pressure < 2.5, if you ever do, pull to the side of the road and find out why!
 

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SL55, 300SE, GL450, Daytona 955i
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also, Merc allows worn and high mileage engines to drop below 0.5bar when its hot outside, Merc service guide consider that normal as long as higher pressure registers when you step on the accelerator
 

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F250 7.3TD Mercedes Benz W140 S600 1996 119k k's(sold), MB W124 300E 1989 261k k's(sold)
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Page 86 of the '97 Owners Manual just says it's OK if it drops at idle so long as it rises immediately upon acceleration.
I notice my sons E300 (260,000ks) drops to 1.5 at idle and rises immediately on acceleration to 3.
On my S600 (107,000ks) - the oil pressure guage seems glued to 3 the entire time when the engine is running.
 

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1997 S600 (sold)
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4,660 Posts
SimonClaringbold said:
Page 86 of the '97 Owners Manual just says it's OK if it drops at idle so long as it rises immediately upon acceleration.
I notice my sons E300 (260,000ks) drops to 1.5 at idle and rises immediately on acceleration to 3.
On my S600 (107,000ks) - the oil pressure guage seems glued to 3 the entire time when the engine is running.
My S600 also stays at 3 a lot until it's very warmed up, then it'll drop to 2.5 or 2 at idle.

For another data point, my 1978 911 idles at 1 bar when warm, then goes up about 1 bar per 1,000 rpm.

As long as you don't drop to zero and you see an immediate increase in pressure to 3 bar with increased rpm, you're good.

Brett
 

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S600 C140 1994
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537 Posts
Discussion Starter #10
Thanks guys!!
This was just what I was hopping to hear!
Then everything seems to be in order.

Why I asked is because I saw a picture of the interior of a S600 1994 that was parked on idel with warm engine and a pressure of 3 bar. (?)

I guess it´s also depending on what "thickness" the engine oil has.
 

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92 500SEL to 01 E320T current 2014 lexus LS460
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Mine seems to run higher with SYNTH, of course you cant believe MB any more. My last oil change started with dino oil, charge which was deleted and SYNT substituted.
I am really starting to question some past invoices, the service writers are becoming slippery.
 
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