Howdy,

I've got an 1983 240d with and automatic trans.

On start up the oil pressure gauge reads zero, then after about a 6count it 'pops' or clicks up to about 25-30 psi at idle. Pressure is always on the max peg of 45 when its above idle. When Idling at a light while in drive it does drop to about 15 or so. If I I go to park at idle it will jump up to about 25-30. I know the trans is bogging it down when stopped and idling.

I'm wondering if this delay in pressure coming up on starts could be a sign of my oil pump failing... ie its taking some time to prime the pump and the engine is running unlubricated for those critical first seconds after a start.

I run synthetic oil and change it ever 4-6months... the vehicle has been a daily driver and has typically taken a potatoe or two to register oil pressure, but I always assumed it was just air in the line slowing the gauge from registering pressure... but as its gotten worse I'm wondering if it is a sign of the oil pump failing.

As this concerns me I've stopped driving it.

Thanks for your help and insight.

Tom

Mine usually pops up within a count of about 2 or 3. Try replacing the o-rings in your oil filter center rod. Your filter oil may be draining back down in the pan when stopped.

__________________
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

x2 on the o-rings

or

You may have an incorrect or otherwise unsuitable oil filter. Some of the filters made in India or Mexico nowadays may be worse than useless.

__________________
Palangi

2004 C240 Wagon 203.261 Baby Benz
2008 ML320 CDI Highway Cruiser
2006 Toyota Prius, Saving the Planet @ 48 mpg
2000 F-150, Destroying the Planet @ 20 mpg



TRUMP .......... WHITEHOUSE
HILLARY .........JAILHOUSE
BERNIE .......... NUTHOUSE
0BAMA .......... OUTHOUSE

i pulled the filter out... i only see two orings, both are in the filter... the bottom is larger and fits the filter housing, the smaller is at the top of the filter has the rod sliding down through it just fine. I held the canisters oring inplace with some grease and put it all back together.

Oil pressure is still taking a while to come up on the first start of the day... the big question is: Does that mean critical componets aren't getting oil until the pressure 'pops' or is it just taking time to fill the filter and pop the needle.

Thanks for your insight.

Tom

there should be 3 o-rings.
one on the lid of the housing, and two small ones at the bottom of the rod

__________________
1981 NA 300D 310k miles

Should be two o-rings that fit in the two grooves towards the bottom of the shaft that is attached to the lid of the filter. Maybe they are completely missing. That would account for what is happening. They are the diameter of that small shaft. Maybe 3/8".

__________________
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

Both. Change "or" to "and."

There should be two small o-rings on the lower end of the stand pipe that is part of the filter lid. If they are not installed and working, your filter housing will drain when the engine is not running.

__________________
When cryptography is outlawed, bayl bhgynjf jvyy unir cevinpl.

I don't understand. Why are you changing your oil every 4-6 months? Are you driving 25,000-30,000 per year?

__________________
Strelnik
Invest in America: Buy a Congressman!

1950 170SD
1951 Citroen 11BN
1953 Citroen 11BNF limo
1953 220a project
1959 180D
1960 190D
1960 Borgward Isabella TS 2dr
1983 240D daily driver
1983 380SL
1990 350SDL daily driver alt
3 x Citroen DS21M, down from 5
3 x Citroen 2CV, down from 6

Have you tried using a different pressure guage?

__________________
RRGrassi


70's Southern Pacific #5608 Fairmont A-4 MOW car

13 VW JSW 2.0 TDI 193K, Tuned with DPF and EGR Delete.

91 W124 300D Turbo replaced, Pressure W/G actuator installed. 210K

90 Dodge D250 5.9 Cummins/5 speed. 400K

I was going to suggest that the needle on the gauge could have static holding it to the post. When I repainted my needles on my instrument cluster that exact same thing happened to me. I ended up taking out the cluster again and putting of drop of dishwater soap mix on both and letting it dry naturally. Problem solved. Wiping with a dryer sheet would accomplish the same thing.

ok... so time to track down the orings...

and to answer someones question... from where I stand oil changes are not just by millage... the rust preventive additives in engine oil have a lifespan as well... and seeing I'm not sending my oil out for analysis, I change it every 4-6 months just to be sure... my 240D is a daily driver and gets about 15 miles a day put on it when I'm commuting with it... my other vehicle is a millitary 6.2 GM Diesel blazer that is for hunting and is also tags in for a comute or two a week... though I've curbed my 240d for the most part until I've got this nailed and been driving my blazer nearly exclusively... the blazer gets the same oil changes and TLC.... synthetic oil and changes every 4-6months... seeing neither get all that many miles on them

Rust preventatives?? Inside the engine?

__________________
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

In Trade School back around 1975 they said that the additives in Oil have been depleted even if the Vehicle sits for 6 months and is not used.
That was 1970s Oil and we were not told what specific additives deplete.

On the other hand over on another forum a person said that when you first put the Oil in the Engine it has a high Detergent content and the high Detergent content caused more wear than after it is depleted/used up. The post said that changing the Oil too often causes extra wear because you are keeping the Detergent content high.

To add more to the mix People who install Bypass Oil filters are often extending/delaying their Oil Chang and many are not adding extra additives in between to make up for the Oil Being in longer. They are often using Oil Analyses to support what they are doing.

Does this mean better Filtration is more imprtant than addatives?

__________________
84 300D, 82 Volvo 244Gl Diesel

yes, oil has additives that prevent corrosion, some of the additives also help with water entrainment. I know a little about this from being a pilot... first of all the water entrainment additives in jet turbine oil are severe skin irritants... especially to me personally. Also if you sit a piston airplane you should change the oil to a preservative type, then drain and replace it with standard oil when you desire to return the plane to service... or you leave standard oil in and run the engine about once a week ideally for about 30 minutes inorder to heat the oil and get any water in the oil out (yes on a micro level oil will hold water and it will aide in the corrosion process), but still must change the oil based on elapsed time not engine hours while the plane is mostly sitting. This is the same concept on gas or diesel engines though the exact chemistry of the oils is changed to deal with the differing pollutants in the oil due to differing fuels...

none the less if you care about your engine you change oil based on time elapsed, engine hours, or miles driven... if you take samples you should be ready to read the analysis and add additives or change the oils as needed.

my .02 usd...

but back on topic, I think this is part number of the o-ring i need. (peach parts seems to be out): W0133-1644350, and I guess I'll need two of them.

can anyone please confirm?

You need two 6mm x 10mm automotive grade o-rings. Just about any reasonably stocked auto parts store should have them. At a chain parts store, you might need to ask the clerk to check their open stock inventory.

__________________
When cryptography is outlawed, bayl bhgynjf jvyy unir cevinpl.