Just noticed on my 85 300SD that when starting a cold engine, the OP guage takes approx. 3 seconds to go from 0 to 3....needle rises slowly to 3.

Thenl, after the engine is warmed up, it goes to 3 upon starting in about half a second or so.

This normal behavior for the guage on cold starts?

__________________
Chris
1985 300SD - 'Grace' (198K mi.)
2018 Honda Civic Sport
2018 Honda CRV LX
2010 Honda Fit Sport (RIP)
2013 Honda Accord Sport (Sold)
1996 Lexus LS400 (Retired)
1995 Ford Contour SE (Retired)
1976 Porsche 914 (Sold)
1972 Datsun 240Z (RIP)

Chris,

This is normal. You'll also find that as the oil warms, oil pressure will ultimately settle ~1.5 bars at idle.

__________________
Chris

'04 ML500 - 53k, Inspiration Edition, Desert Silver
'11 Audi A4 Avant - Brilliant Black
'87 300SDL sold
'99 C280 Sport sold
'85 190E 2.3 sold

thnx....was hoping this was normal.

Actually tho, when the engine is fully warmed, the guage only goes down to 2-2.5bars. Guess this is good too.

Sometimes it bounces back and forth about 3/4th of a bar in this area between 1.75-2.5 bar....ie, doesn't sit there steady (this is at idle). Is THIS normal?

__________________
Chris
1985 300SD - 'Grace' (198K mi.)
2018 Honda Civic Sport
2018 Honda CRV LX
2010 Honda Fit Sport (RIP)
2013 Honda Accord Sport (Sold)
1996 Lexus LS400 (Retired)
1995 Ford Contour SE (Retired)
1976 Porsche 914 (Sold)
1972 Datsun 240Z (RIP)

I have a 85 300D. My oil guage shoots to 3 immediately on starting. After warming it settles to 1.5 at idle, but goes to 3 again while driving. Is this a problem???

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Gary
85 300D Ivory, 202,000
Beatus exsisto Jesu, verus et Deus verus Vir

This is not normal. Most likely the problem resides with the oil pressure sending unit.

Gary F. - yours functions as it should.

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Chris

'04 ML500 - 53k, Inspiration Edition, Desert Silver
'11 Audi A4 Avant - Brilliant Black
'87 300SDL sold
'99 C280 Sport sold
'85 190E 2.3 sold

Chris:

So regardless of where the needle is sitting, it should always be fairly steady?

__________________
Chris
1985 300SD - 'Grace' (198K mi.)
2018 Honda Civic Sport
2018 Honda CRV LX
2010 Honda Fit Sport (RIP)
2013 Honda Accord Sport (Sold)
1996 Lexus LS400 (Retired)
1995 Ford Contour SE (Retired)
1976 Porsche 914 (Sold)
1972 Datsun 240Z (RIP)

Correct. It should be steady. My experience with pre-'90 MB diesels have allowed me to observe the following characteristics:

Cold start - oil pressure builds from 0-3 at idle.
As engine/oil warms, idle oil pressure will gradually drop to ~1.5-1.8 bars.
When under load, oil pressure will remain at 3.

__________________
Chris

'04 ML500 - 53k, Inspiration Edition, Desert Silver
'11 Audi A4 Avant - Brilliant Black
'87 300SDL sold
'99 C280 Sport sold
'85 190E 2.3 sold

Ok...car is going in to MB Autowerks tomorrow for other stuff anyway so that's just one more thing I'll mention to Donnie

__________________
Chris
1985 300SD - 'Grace' (198K mi.)
2018 Honda Civic Sport
2018 Honda CRV LX
2010 Honda Fit Sport (RIP)
2013 Honda Accord Sport (Sold)
1996 Lexus LS400 (Retired)
1995 Ford Contour SE (Retired)
1976 Porsche 914 (Sold)
1972 Datsun 240Z (RIP)

I used to have this on an old Humber a few years ago, An old Mechanic I knew pointed out the problem, It was air in the pipe connecting he guage to the engine, I bled this out, and guage worked normally from cold.
I recently had to replace the oil guage on the 300D, and forgot to bleed it out, sure enough, it took about 5 seconds to climb its way to 3 bar, After bleeding its practically instantanious, even when cold. Oil pressure hot is about 2 bar, but when running for about 5 hours, ( a run to London and getting stuck in traffic) that pulsing effect showed itself, but the average pressure was still 2 bar at idle, with my car too. I have not had any other problems, and it only happens after an extended run. Odd Innit??

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http://i190.photobucket.com/albums/z...0TDnoplate.jpg

Alastair AKA H.C.II South Wales, U.K. based member

W123, 1985 300TD Wagon, 256K,
-Most recent M.B. purchase, Cost-a-plenty, Gulps BioDiesel extravagantly, and I love it like an old dog.

W114, 1975 280E Custard Yellow,
-Great above decks needs chassis welding--Really will do it this year....

Alastair...you had me going there for a minute. I was thinking BINGO! until I read Bill's comment that my system is electronic LOL!

Bill....sounds good. I'll definitely get those orings changed at the next oil change. Even if it doesn't fix it, it's one less thing that could be causing the problem PLUS it's prolly just good sense to replace them after a while anyway.

__________________
Chris
1985 300SD - 'Grace' (198K mi.)
2018 Honda Civic Sport
2018 Honda CRV LX
2010 Honda Fit Sport (RIP)
2013 Honda Accord Sport (Sold)
1996 Lexus LS400 (Retired)
1995 Ford Contour SE (Retired)
1976 Porsche 914 (Sold)
1972 Datsun 240Z (RIP)

I wonder if my 84 SD is the same. Can I pull my cluster without dealing with an oil line?

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Bob Roe
Lehigh Valley PA USA
1973 Olds 88, 1972 MB 280SE, 1978 Datsun 280Z, 1971 Ford T-Bird, 1972 Olds 88, 1983 Nissan Sentra, 1985 Sentra, 1973 230.6, 1990 Acura Integra, 1991 Volvo 940GLE wagon, 1983 300SD, 1984 300SD, 1995 Subaru Legacy L wagon, 2002 Mountaineer, 1991 300TE wagon, 2008 Murano, 2007 R320CDI 4Matic 52K, some Hyundai, 2008 BMW 535xi wagon, all gone... currently
2007 Honda Odyssey Touring, 2014 E350 4matic