The W123's have that three bar guage. My 85 300D sits at 1.6 bars at idle and doesnt lose much oil...my 240D had oil pressure of 1.9 bars at idle, but its defunct and crashed now...anyone have any data on idle oil pressure? Tried the Search Forum , but 330 messages are 2 many to read....

Mine is about the same as you guys. They say the most important thing is how quickly the gauge rises from idle when you step on the gas. It should snap to full pressure without much delay on a healthy engine. Mine does that. But I do lose some oil, 2-3 quarts between oil changes, especially if I do lots of highway driving. But a lot of that is leaks. I've got a pretty good one going somewhere around the injection pump.

__________________
'81 300TD turbo <<sold 12/05 to another diesel nut

My 85 300D (194k) idles 2 bar. Is this a problem? Actually 3 bar after just starting the engine, then goes down to 2 bar eventually.

No problem at all.

My idle oil pressure is about 1.5 bar (at hot idle; cold idle jumps straight up to 3).

IIRC, anything below 1 bar is something to be concerned about...

Funny you guy's should ask that, as I was reading about the oil system last week in shop manual. It stated in one place that normal hot oil pressure was anything 1 bar or over, but in another spot it stated anything at idle above .5 bar was exceptable. I would say none of you have anything to worry about. My 240D has to have been running 70+ mph for a 150 miles before it will drop to just under 2 bar.

1.0 B = 14.7 psi
1.5 B = 22.0 psi
2.0 B = 29.4 psi
2.5 B = 36.8 psi
3.0 B = 44.1 psi

__________________
'10 Chrysler T&C Stow-N-Go White. Grandpa's ride.

'13 Chrysler 200 Touring Candy Red. Grandma's ride.

Age and cunning will always over come youth and vigor.

Both of our SD's idle just above 2 when warm from normal driving, or at just under 1.5 for mine after I have been doing some speedy driving, probably because the valve to the oil cooler is fully open, causing a slightly lower overall pressure, because the cooler is always hot when it falls to 1.4 bar or so, but not even warm when its up around 2.1 I can actualy observe this valve switchover, if I come off the freeway and its at 1.4, after a few mins idling at the traffic light, it actually just suddenly jumps back up to 2.1, due to the valve closing. On cold starts its always up at 3 right away. After our oil changes both took about 3-4 seconds at idle to climb up to 3, which is plenty fast.....I filled the filter housing with oil to help them out however, I just think its a good idea.

__________________
-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)

Turbo models should be near 2 bar because that it the pressure the oil sprays open. A little less (1.5 bar) is OK.

My 300D sits at 2 bar with an occasional twitch upwards hot, 3 bar (pegged) cold (Mobil Delvac 1 5W40).

The TE sits at 1.5 bar, and the old 220D even manages 18-20 psi hot.

Non-turbos are lower, less oil pump and no oil jets, above 1 bar is fine, 2 bar is great. My brother's 300D only comes down off 45 psi when it's hot, otherwise it's pegged all the time (we got the bearings nice and tight!).

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

hmm. after a high speed run.. (as if i can manage that).. my idle goes to just a tad above 1bar... but on regular driving.. it happily idles around 1.6.

__________________
Mike

----------------------------------
1975 200 - Sold (no pix);
1978 200 - Sold - http://www.pbase.com/hboy/redbaron
1979 300TD - Sold
http://www.pbase.com/hboy/greenwagon
http://www.geocities.com/hboy726/300TD.html
1985 230E - now my daily driver...

84 300SD

3 bar until warm at which time it drops to 2 bar.

It pegs out at 3 bar at about 1200rpm.

__________________
1998 W202 C230 - The money pit of late.
1984 W126 300SD (356,800 miles) Gone to the wrenchapart
1984 W123 300D Gone to the wrenchapart
1972 W108 280SE 3.5 (sold but not forgotten)
1986 Buick Grand National 3.8l Turbo (86k miles)
1966 Glassic Model 'A' Replica http://www.glassicannex.org

http://banners.wunderground.com/weat...Round_Rock.gif

Oil pressure at idle is relative to engine rpm, and temperature. If your engine idles above 700 rpm fully warmed up, (603) oil pressure will be higher than say 650 rpm.

After installing new O-rings to the oil filter center tube, my oil pressure rose from a steady 1.5 bar to just under 2 bar @ 650 rpm. It also now twitches up to above 2 bar for a second or two every 10 seconds.

At or around 800 rpm, oil pressure jumps to just under 3 bar, and at 1000 rpm pegs above 3 bar.

Running 5W40 mine is right at 1.9 after a freeway run, quickly pegs the needle with just a touch of the right foot.

174K miles.

Kevin

__________________
'85 300SD

hah! I'm here to confuse things. Pegged over 3 bar at idle when cold, right around 1 bar, even a shade less when nice and hot. Any mild increase in RPM and it shoots right up.

__________________
'82 300SD - 361K mi - "Blue"

"Good judgement comes from experience. Experience comes from bad judgement."

listen, look, .........and duck.

My '85 300td is at 3 cold, 1.6 when good and hot. A tap on the throttle and it pegs at 3.

Recently I switched oils. I used to use Castrol Dieselall but am now using Rotella and it seems to me my oil pressure picked up a little. You guys think this is possible? I think it used to be at the 1.5 bar using the castrol.

Cheers,

Bill

3.0B climb from 0B, cold start, idle
1.5B momentary low while stopping after 50+ running, hot [edited]
2.0B recovery after stop, idle, hot [edited]
3.0B by 1,000-1,500 rpm, hot

Sounds like I'm middle of the pack.

Best Regards,
Jim

Mine stays at about 1.5 around town but right after I get off the highway on a hot day it will go down to 1bar. But my needle will stay just below 3bar until 2k-2.5k rpm then it goes to 3 bar.

Maybe I need to check my oil pump?

__________________
2016 Corvette Stingray 2LT
1969 280SE
2023 Ram 1500
2007 Tiara 3200