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 11-03-2006, 09:09 PM
Dale 240D
 
Join Date: Mar 2006
Location: Gainesville, Fl
Posts: 84
Unhappy W123 Oil Pressure Drop

Just nursed my 83 240D home. I was driving from gainesville,fl to starke to see Blackfoot in concert!! 10 minutes outside of town i notice my oil pressure gauge dipping. I've never seen it below 2 while at speed. I was going about 45 mph. Terrified, i pull over to turn around and head home. It continues to drop to a little below 1. I pull into a parking lot and as it's idling , the pressure goes back up!!! It stays up as long as I don't go above 35mph. at idle, it's pegged. At about 30-35mph it's around 2, Above 35mph it drops off quickly. I had just topped the oil off right before starting out on the trip. 2 weeks ago a compression test came back 300,300,400, 300. I have about 190k miles on her. I've NEVER had this car give me oil pressure problems. Also my understanding was that as a pump started to go bad, it was at low rpm when you would notice it first. Any clues, comments or suggestions gentlemen?(and ladies if there are any out there!)

Dale

Reply With Quote
  #2  
Old 11-03-2006, 09:29 PM
Bruce Kennedy's Avatar
Glutton for punishment
 
Join Date: Oct 2006
Location: Cincinnati Ohio
Posts: 230
How many miles are on her? Any leaks? Any unusual noises like a rod?

81 240d 140k rusty but runs great
85 300d 319k " its alive!"
85 300td 149k
83 300d 187k
84 300d 287 parting out
Reply With Quote
  #3  
Old 11-03-2006, 09:29 PM
Registered User
 
Join Date: Jan 2002
Posts: 18,350
Sounds to me like the pick up screen may be getting clogged. The more suction the pump produces, the tighter it is clogging the screen? You could drop the lower sump and get a look at it.
__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13
Reply With Quote
  #4  
Old 11-03-2006, 09:31 PM
ForcedInduction
Guest
 
Posts: n/a
First of all, stop driving it with this problem.

If you have no external leaks, I'd bet on the oil pump, pump pressure regulator, or clogged pickup screen/oil filter.
Reply With Quote
  #5  
Old 11-03-2006, 09:33 PM
Dale 240D
 
Join Date: Mar 2006
Location: Gainesville, Fl
Posts: 84
no leaks and no noises, 190,000 miles. clogged screen sounds like a nice problem to have. i'll drop the pan tomorrow and take a looksy and post back. thanks guys.

Dale
Reply With Quote
  #6  
Old 11-04-2006, 12:16 PM
Dale 240D
 
Join Date: Mar 2006
Location: Gainesville, Fl
Posts: 84
Alright. Got up this morning and figured I'd drive around and see if my problem was still there. Started up, pressure went straight up to 3 barr and stayed there. drove around for about 20 minutes, went to the auto zone to get oil for the change since i was going to drop the pan. NEVER dropped below 2 barr.
I dropped the pan and it is IMMACULATE. i mean i'd eat off of it. no gunk or sludge or metal bits. so i'll just clean it up a little bit and put her back together. This leaves me wondering what happened last night? can an oil gauge act screwy? it's a pretty simple device with no electrics involved. was my pump maybe sucking something up and eventually just digested it adequately so that flow resumed? did something maybe oclude where the sensor is? where is the sensor by the way? maybe i should pull that and look at it.
Thanks for opinions.
Dale
Reply With Quote
  #7  
Old 11-04-2006, 12:29 PM
Registered User
 
Join Date: May 2004
Location: Flowood Mississippi
Posts: 438
Oil pressure drop

You could always tee off the filter output with an additional line to a temporary real oil pressure gauge mounted in the cabin to confirm this is not just instrument error or malfunction but a real drop....the little holes in the linkage and the brass pivots can wear to cause erratic readings in these old gauges...never hurts to have a little more information...
Reply With Quote
  #8  
Old 11-04-2006, 12:33 PM
Stevo's Avatar
Registered User
 
Join Date: Apr 2002
Location: NW WA
Posts: 6,299
[QUOTE=Dale240D;1321514] I've never seen it below 2 while at speed.

Does this mean your oil pressure gauge is NOT "pegged" all the time when you are driving?

Scretch that, I mis-read your post doh

__________________


1985 Euro 240D 5 spd 140K
1979 240D 5 spd, 40K on engine rebuild
1994 Dodge/Cummins, 5 spd, 121K
1964 Allice Chalmers D15 tractor
2014 Kubota L3800 tractor
1964 VW bug

"Lifes too short to drive a boring car"

Last edited by Stevo; 11-04-2006 at 07:55 PM.
Reply With Quote
Reply

Bookmarks


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 05:42 AM.


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