Parts Catalog Accessories Catalog Tech Info Tech Forums
  Search our site:    
 Cart  | Project List | Order Status | Help    

Go Back   PeachParts Mercedes ShopForum > Technical Information and Support > Tech Help

LinkBack Thread Tools Display Modes
Old 11-03-2000, 09:56 AM
Posts: n/a
Hi all!

I never really took much notice about the oil pressure reading upon start-up until recently. I know the greatest stress on an engine is on start-up when it is less lubricated, and I was wondering after a long or over night sitting, how soon or how fast should the oil pressure needle jump from 0 to 3? My 190E first goes in between 0 and 1 and then jumps to 3 within 2-4 sconds. What is the normal time it should move up to 3? Is it immediate upon start-up? My needle has a few seconds pause before it does. Thanks.
Reply With Quote
Old 11-03-2000, 10:19 AM
Registered User
Join Date: Jul 2000
Location: Toronto, CANADA
Posts: 1,193
The oil pressure needle on my 420SEL always goes right to 3 on start up and stays there for a few minutes until it settles at idle. The only time I have had a delay is right after I change the oil. Even then it is only like 3 seconds before the pressure guage goes up to 3.

Jason Priest
1986 420SEL
Reply With Quote
Old 11-03-2000, 10:51 AM
elau's Avatar
Registered User
Join Date: Nov 1999
Location: MD.
Posts: 1,725
My gauage always goes to 3 the instant I start the vehice, and stay at 2 while idling.
Although mine never goes to 1, is oil pressure at 1 is a bad thing? How about someone shed some light on this subject?

95 R129
98 ML320
Reply With Quote
Old 11-03-2000, 12:03 PM
Join Date: Mar 1999
Location: Tucker, Ga USA
Posts: 12,153
As long as the gauge reads at least .5 Mercedes says that is enough for a hot engine at idle. Each number is equal to 15lbs of oil pressure. Hope that helps. Most common failure is the sending unit!
Reply With Quote
Old 11-03-2000, 02:12 PM
Posts: n/a
Oil Pressure at startup is always higher than after warmup. The important parameter would be oil pressure after thorough warmup. If it is low at that time(below .5 Bar) would be worrisome.

Good luck,

Larry Bible
'01 C Class, Six Speed
'84 Euro 240D, manual, 533K miles
'88 300E 5 Speed
'81 300D Daughter's Car
Over 800,000 miles in
Mercedes automobiles
Reply With Quote
Old 11-04-2000, 05:20 PM
Posts: n/a
If it is below .5, that is worrisome....why does the gauge go up to 3? Isn't that the design criteria that it should read around the 3 mark when the engine is warmed up? My 420 SEL reads 2.5 always---should I worry? Heard alot of discussions on the the infamous oil pressure gauge. Would appreciate your comments.

Michael Jay
1989 420 SEL
Reply With Quote
Old 11-04-2000, 07:33 PM
Posts: n/a

Does the oil pressure not come up to 3 when the engine speeds up? How low does it go when warmed up thoroughly and idling?

Good luck,

Larry Bible
'01 C Class, Six Speed
'84 Euro 240D, manual, 533K miles
'88 300E 5 Speed
'81 300D Daughter's Car
Over 800,000 miles in
Mercedes automobiles
Reply With Quote
Old 11-05-2000, 11:44 PM
Aaron's Avatar
Join Date: Aug 1999
Location: Cincinnati, Ohio
Posts: 1,935
The gauge will peg 3 bar just after startup and will remain there until the engine warms up and the oil thins out some. 1.5 bar is correct pressure at idle at normal operating temp. Some of the larger engines such as the M-100 (6.3, 6.9) and the M-120 (V-12) will idle with the needle around 1 bar or 15psi when warm and at idle. It's just characteristic of the big engines. As long as oil pressure rises immediately upon acceleration, you have nothing to worry about. Funny this thread came up, as I had a '75 450SL in the shop the other day with 283,000 miles on it and when I was on the freeway on the test drive, the oil pressure gauge didn't even peg full pressure at 70mph. I'd say the mill was just a little worn

By the way, you guys with 380s, 420s and 560s, I would strongly recommend "priming" the engine after an oil change. To do this, look on the driver's side inner fender well for a black box (the ICU) which will have a plug with a green wire connected to it. Pull the plug and crank the engine over for about 15 seconds then re-connect the plug and fire it up. This will get the oil pressure built up to avoid a "dry" start.

Aaron Greenberg
MB technician
Mercedes-Benz of Cincinnati
'67 250SE Cabriolet
'77 450SL
'80 300SD
'85 380SE
'86 420SEL
'89 420SEL
'93 300E 2.8
'74 Jensen Interceptor Mk.III
'81 DeLorean DMC12
'84 BMW 745i Turbo

[This message has been edited by Aaron (edited 11-05-2000).]
Reply With Quote
Old 11-08-2000, 09:39 AM
Registered User
Join Date: Aug 2000
Location: Livonia, MI USA
Posts: 99
Can I "prime" my 240D oil system after an oil change? I just noticed that the gauge took several seconds to move off zero after changing oil. With spin-on filters, I always fill 'em up before spinning on. But there seems to be no way to do that on my '79 240D (616 engine). Thanks.
'79 240 Wiesel automatic
'95 Olds Gutless Cruiser
'73 Citroen SM 3.0 5-speed
Reply With Quote


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

Similar Threads
Thread Thread Starter Forum Replies Last Post
The oil debate again What do you think of this dpbrowne Diesel Discussion 101 04-01-2005 02:33 PM
Ode to the 2.4...50k with no oil pressure! MercedesRover Diesel Discussion 2 12-08-2004 09:13 PM
Low engine oil pressure LEADFOOT Tech Help 30 11-19-2004 10:46 AM
Mobil1 15w50 in Cold Weather jjalex Diesel Discussion 30 01-21-2004 03:54 PM
Kablam !! Big bang. Cracked valve cover Anon-E-Mouse Diesel Discussion 49 07-27-2002 04:01 PM

All times are GMT -4. The time now is 11:48 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2016, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2011 Pelican Parts - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page