Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help




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

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 12-10-2003, 09:31 AM
DaimlerChrysler's Avatar
Registered User
 
Join Date: Mar 2002
Location: Lexington, Kentucky
Posts: 132
Question Oil Pressure gauge

I've had my '84 380SL for 2 years now and have had very few problems(knock on wood), but there is a problem that keeps nagging at my sense of well being.

When cold the oil pressure gauge pegs at the top like it's suppose to, but when it's warm (the car) the gauge rarely goes below between 2 and 3. Is this normal? I've had nothing but diesels so I don't know what it's suppose to do after warmup. The car has 125K on the clock but due to a timing chain break the PO had all of the valves and guides replaced.

Thanks!
__________________
Old age and treachery will allways overcome youth and skill!

1993 S500
1984 380SL
Reply With Quote
  #2  
Old 12-10-2003, 11:18 AM
G-Benz's Avatar
Razorback Soccer Dad
 
Join Date: Apr 2001
Location: Dallas/Fort-Worth
Posts: 5,711
It varies from one model to another, but what you are observing is quite normal.

When your oil pressure sensor goes bad, it will either peg to '3' all of the time (including when you just insert the key and turn it) or not function at all.
__________________
2009 ML350 (106K) - Family vehicle
2001 CLK430 Cabriolet (80K) - Wife's car
2005 BMW 645CI (138K) - My daily driver
2016 Mustang (32K) - Daughter's car
Reply With Quote
  #3  
Old 12-10-2003, 11:28 AM
Senior Member
 
Join Date: Jun 2001
Location: Northern Calif. (Fairfield Area)
Posts: 2,225
Diesel or gas doesn't matter. Normal for at a truly warm MB is between 1 and 2 atmospheres, so staying at 3 is not really normal assuming normal idle speed of around 650 on that car since it is not adjustable. If you are idling much higher, there is a problem in your air management system. Also what weight oil are you using?

P/S As a card carrying nudist, I can assure you that you can add to your fun by becoming a nudist. Check with AANR (American Association for Nude Recreation) on the internet for the location of a resort near you. You can spend a day as a guest and find out how nice and friendly everyone is. It may change your life.

Peter
__________________
Auto Zentral Ltd.
Reply With Quote
  #4  
Old 12-10-2003, 05:57 PM
DaimlerChrysler's Avatar
Registered User
 
Join Date: Mar 2002
Location: Lexington, Kentucky
Posts: 132
It's running at about 650rpm which I understand is normal...any guess as to what it might be? I use 5W30


BTW, since I've been told that I look like Winston Churchill I think that I'll decline the offer for the Nudist organisation!
__________________
Old age and treachery will allways overcome youth and skill!

1993 S500
1984 380SL
Reply With Quote
  #5  
Old 12-10-2003, 06:37 PM
Registered User
 
Join Date: Oct 2002
Location: Colorado Springs
Posts: 481
The oil pressure should sit at three at start up as she warms up it can go down to .6 bar before you should be concerned the lighter the oil the lower the pressure most of the time (synthetics also tend to lower the pressure but only marginally). At park running and engine warm .6 to three is fine as long as it goes straight to 3 on acceleration. Hope this helps. 5w30 is a light oil i would use 10w 40 as a minimum unless you live in the very cold climates. Do not mean to get an oil discussion going. Personally I like mobil15w50 as it covers my area's temps very well. A oil sensor can give wierd readings so that is a good place to start if you are concerned. My 560 sits at 2 bar in idle warmed up.
m
__________________
Martin Ingram
Colorado Springs
2005 320 CDI
2006.5 VW Jetta TDI
1991 560SEL (179000 Sold)
1972 280SEL 4.5 ('The Lead Sled' 320000 miles when sold.)
1972 220D (225000 when sold)

Last edited by mhingram; 12-10-2003 at 06:43 PM.
Reply With Quote
  #6  
Old 12-11-2003, 11:36 AM
Senior Member
 
Join Date: Jun 2001
Location: Northern Calif. (Fairfield Area)
Posts: 2,225
I'll concur with Martin on his complete post. May be a funky gauge. I also would recommend heavier oil. I run 20-50 in all my gas and diesel rigs here in the S.F. bay area. It is amazing that your reading is 2 to 3 with oil that light. If you shift to heavier oil it will probably exacerbate the problem. Check your owner's manual (you know that little book in the glove compartment that is still in mint condition) to see what is recommended for your climate.

Peter
__________________
Auto Zentral Ltd.
Reply With Quote
  #7  
Old 12-11-2003, 07:30 PM
Registered User
 
Join Date: Oct 2002
Location: Colorado Springs
Posts: 481
I just checked today it is 2.3 in P idle and 2 in D idle usin Mobil 1 15w50
__________________
Martin Ingram
Colorado Springs
2005 320 CDI
2006.5 VW Jetta TDI
1991 560SEL (179000 Sold)
1972 280SEL 4.5 ('The Lead Sled' 320000 miles when sold.)
1972 220D (225000 when sold)
Reply With Quote
  #8  
Old 12-11-2003, 09:37 PM
Registered User
 
Join Date: Aug 2002
Posts: 179
Autozen

If you are a card carrying nudist, where do you carry the card?

:->

Tower
Reply With Quote
  #9  
Old 12-11-2003, 11:02 PM
PaulH's Avatar
Registered User
 
Join Date: Dec 2002
Location: Annapolis,Md
Posts: 431
Warm engine in my SDL shows 3 bar at highway speeds and 1.8 bar at 630 RPM idle. This using 15w-40 Rotella (dino) oil. Oil changed every 3000 miles. Engine uses maybe 1/3 quart between oil changes and has used this amount since new.
__________________
Paul 1987 300 SDL; 2000 ML; '69 MGB; '68 VW Fastback
Reply With Quote
  #10  
Old 12-12-2003, 12:02 AM
Senior Member
 
Join Date: Jun 2001
Location: Northern Calif. (Fairfield Area)
Posts: 2,225
Tower,

Once you check in you don't need your card or wallet, but if you want to buy dinner or a soda or something, you carry money in an amulet pouch on a leather thong around your neck. My daughter made a beautiful pouch for me as a gift. She is still not a nudist, but her boyfriend , Scott, is trying to convince her. When you go to a nudist resort you don't find just beautiful bodies. You find people as they are. Some people are 75, some people are 14, some people are 10, some people have had a breast removed, some people have had a tripple bypass, some people are pregnant, some people are having a period, some people have a microscopic penis, some have beautiful bodies. The point is that nudists accept people as they are. I'm not coming down hard on you, man. I know you are funnin with me. So relax and check it out. I'm tellin you it is the most fun you can have with your clothes off. Don't worry, if you ask a lady for a slow dance, you won't get a boner.

Peter
__________________
Auto Zentral Ltd.
Reply With Quote
  #11  
Old 12-12-2003, 03:03 AM
Lok Lok is offline
Registered User
 
Join Date: May 2001
Posts: 5
I have a 1992 300SEL (W140). The oil guage works funny too. It fluctuates a lot during idle eventhough the engine's rpm is very stable. At idle, the rpm stays just a little above 500. Could this be linked to a bad oil sensor or a bad guage? I will be taking it in for repair. Someone stole my badge on the hood and the engine won't start without manually applying the throttle pedal. But once it starts it is very smooth except for the oil pressure guage.

Lok
Reply With Quote
  #12  
Old 12-12-2003, 11:49 AM
Senior Member
 
Join Date: Jun 2001
Location: Northern Calif. (Fairfield Area)
Posts: 2,225
Lok,

More than likely it is the sending unit. MB oil pressure gauges used to be bullet proof, but the quality went down in the mechanical guages to where the unit in just about every 123 chassis leaked oil. Now the electrical units are becoming par with the junk made for Detroit Iron.

Peter
__________________
Auto Zentral Ltd.
Reply With Quote
Reply

Bookmarks

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 On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -4. The time now is 03:31 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, 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