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-Benz Forum > Mercedes-Benz Tech Information and Support > Diesel Discussion

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 05-18-2009, 03:36 PM
Registered User
 
Join Date: Aug 2006
Posts: 23
oil press @ idle lowering over time

HOLA el grande diesel hombres;
Ive been noticing lately my idle oil pressure when hot after 30 minutes @ highway speeds has gone from about 1.3 bar to 1 bar. Over a period of about 3-4 months. The last months @ winter temps of course.
My sled is a 83 300sd w/ 230k
Pressure is 3 bar @ startup in morning and pegs @ anything over 1300 rpm and immediately upon acceleration.

Last oil change was 1500 mi ago. My son did it and used (ugh!) regular exxon 10/40.
Im sure my valve guide seals may be going. Slight leak from oil filter housing and from oil dipstick tube @ block. What would you suggest to get the pressure up?
What oil should I put in (Im going to change it out) to go in hottest weather? Should I up the weight? Will going full syn help?

I absolutely LOVE this car, at present slightly more than my son, and want the best fix.

Reply With Quote
  #2  
Old 05-18-2009, 03:50 PM
awsrock's Avatar
Registered User
 
Join Date: May 2008
Location: Tinley Park, IL
Posts: 642
1 bar is still fine, as long as it goes up upon using the throttle. How long have you had the car?

I find that my oil pressure responds to temperature and humidity differently..i.e., the lowest I've seen it go was always on very humid, rainy days. Not sure why...

10w40 is fine for warm weather, but you can also try 15w-40. Going synthetic shouldn't make much difference, but with a synth 5w-40 you might actually see the oil pressure go down even more, just becasue it flows better.
__________________
Dan
2005 E320 CDI - 246k
1987 300SDL TD05-16g, Herlevi pump, Elbe manifold, 2.47 LSD - 213k
Past: 1987 300D - 264k
Reply With Quote
  #3  
Old 05-18-2009, 03:53 PM
pawoSD's Avatar
Dieselsüchtiger
 
Join Date: Oct 2004
Location: Grand Rapids, MI
Posts: 15,438
1. 10w40 regular oil should be REMOVED ASAP from the engine, that is not a diesel oil and has nothing in it to help trap soot particles and cannot stand the higher pressures in a diesel, it will increase wear on the engine

2. 1-1.5 bar after a hot highway drive is normal, as long as it pegs back up to 3 at anything above 1200-1300rpm.

3. Valve guide seals are not a common maintenance issue for this engine, most never need it, and they have nothing to do with your oil pressure.

4. More likely your problem is due to the gas engine oil you are running, it may be breaking down. CHANGE IT with diesel oil! I'd use a 5w40 synthetic DIESEL oil of your choice.

Hopefully this helps. I'd get that gasser oil out of there right away though.
__________________
-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)
Reply With Quote
  #4  
Old 05-18-2009, 04:11 PM
Registered User
 
Join Date: May 2007
Location: Out in the Boonies of Hot, Dry, Dusty, Windy Nevada
Posts: 9,649
The SD uses an electric oil sending unit. as you said, this has happened in the last 3 - 4 months. so maybe it is becoming a little faulty.

I won`t get into the oil debate, but, any oil is better than no oil.
the Diesel oils are formulated differently than the Gasser oil.

Charlie
__________________
there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works
Reply With Quote
  #5  
Old 05-18-2009, 06:33 PM
pawoSD's Avatar
Dieselsüchtiger
 
Join Date: Oct 2004
Location: Grand Rapids, MI
Posts: 15,438
True, the sender may be ailing. But still change out that gasser oil!

If you replace the electric sender, be sure to buy a VDO unit if you buy a new one.
__________________
-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)
Reply With Quote
  #6  
Old 05-18-2009, 09:36 PM
ForcedInduction
Guest
 
Posts: n/a
Oil loses the effectiveness of its velocity additives over time. Its one of the reasons oil is changed frequently instead of just leaving it in forever.

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 11:56 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2018 Pelican Parts, LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page