Oil consumption W123 240D - PeachParts Mercedes-Benz Forum

koooop · #1 06-02-2016, 11:34 PM

Just over 3,500 miles since I bought a 1981 240D, fresh oil change at purchase and I put in a quart. I have Zero idea how much oil this 240D should use, does that sound about right for 158,000 miles on this antique?

The book says oil changes at 5,000, I plan follow MBZ recommendations.
Says

mistersooty · #2 06-02-2016, 11:51 PM

Prepare for a whole host of answers.

From my experience that oil usage sounds excellent and many of us can only hope for that level. Sounds like you got yourself a good one that's just broken in

The oil usage on my 240D depends on how I drive it. I've driven flat out for 6 hours across SD on vacation and had to replace the better part of a quart. Normal driving maybe a quart every 2000 miles.

koooop · #3 06-03-2016, 12:03 AM

It's a 240D, I'm pretty sure foot on the floor is the only throttle position.

I'm not babying the car, I've made a few 1 or 2 hour trips at 68-75mph.

I just don't know what to expect from a diesel, it seems good to me but I have no experience here.

barry12345 · #4 06-03-2016, 12:14 AM

Really well above what I consider a decent example. These engines have high piston speeds on the highway. So expect them to burn more oil then. On long highway trips especially.

Remember to check the oil level on long trips. Actually it is still an excellent ideal to check the oil level anytime you fuel. The wife and myself have lost the habit especially with our newer cars.

Anything above twelve hundred miles per quart I trust these engines. This is on high speed highway runs.. Burn rate probably depends on the viscosity of oil used somewhat as well. I have noticed a trend of some people using inadequate viscosity oils. I expect this may shorten engine life expectancy over time.

These are a high risk engine of rubber oil cooler lines failing because of age and rot. There is an oil temperature thermostat that directs the oil through the oil cooler hoses at full pressure. Once the oil gets hot enough on the highway.

If one of the two hoses ruptures and it will normally occur on the highway. By the time you notice you have pumped all the oil out and see the oil pressure gauge fall. In ninety percent of cases it will mean the loss of the engine.

It is not human nature to watch a gauge constantly enough. Some diesels have an additional audiable warning system. To me it is important to change these hoses if at all suspect.

Some people have added a low warning oil pressure system backup. I do not blame the manufacturer for this issue. They had no knowledge these cars would remain on the road as long as they have. The choice of preventable maintenance is up to the individual.

But if you have a thirty year plus old hose rupture you will usually be sorry. Unfortunatly most of these old buggies we buy lack any past record of maintenance that has been done over the years. Also as one of the front motor mounts age the pulley sags lower with the engine and can cut into one of these hoses. We periodically get a batch of members that have this issue occur. Then a period where none are reported. Perhaps more than you asked for yet at the same time important to know.

koooop · #5 06-03-2016, 12:31 AM

Thank you, I will ask about the oil lines at the next oil change.

leathermang · #6 06-03-2016, 01:04 AM

That sounds like very good oil mileage..
I suspect most are at the 2000 or less miles per quart level at this time...
To get your results I suspect your valve stem seals are pretty new...

charmalu · #7 06-03-2016, 01:29 AM

Don`t complain, 3500 mile to a qt sound excellent.

Iam up almost 389K on the 80 240D, and we use a qt 1700 - 2000 miles or so.
I just depends how we drive her. I don`t drive with peddle to the floor, and on the Hwy Iam usually 60 - 65 or so.
Most of the roads out here in Nevada where I live are 25 - 45mph. There is a short stretch of freeway that is 65mph.

In Calif where I use to live, the majority of the freeways are 65 and a lot more of that compared to Nv.
I-5 can be 70 75mph.

Charlie

Maxbumpo · #8 06-03-2016, 02:11 AM

Don't chase the upper mark on the dipstick (I don't think you are, but in case you are tempted). When the oil level on the stick reaches the low mark, add one quart, which should put the level midway between the marks. If you chase the upper mark, expect to see an increase in oil usage. The nature of the OM61x engines is to rapidly consume the oil above the midpoint.

leathermang · #9 06-03-2016, 10:04 AM

Quote:

Originally Posted by Maxbumpo

Don't chase the upper mark on the dipstick (I don't think you are, but in case you are tempted). When the oil level on the stick reaches the low mark, add one quart, which should put the level midway between the marks. If you chase the upper mark, expect to see an increase in oil usage. The nature of the OM61x engines is to rapidly consume the oil above the midpoint.

I was just about to come back and add that information... many people in the archives over the years have reported that if the oil level is above the half way between the lines point it really increases the oil usage..
ALSO... if someone has really high oil consumption.. check to see if the proper color dip stick is in your car... the wrong length , indicated by color , has been reported in the past also...

thatguy · #10 06-03-2016, 11:37 AM

My '95 OM606 doesn't drink any oil in 5k oil changes, but I also found my 300SD would consume oil when above the halfway mark on the dipstick, as noted above. It was odd, it would drink about 3/4 of a quart within 1500 miles, then once it reached the halfway point on the dipstick things wouldn't change no matter how I drove it, or even if I ran it a little too long between changes.

koooop · #11 06-03-2016, 03:49 PM

I don't add oil in any car unless it's at the bottom of the dipstick.

I appreciate all of the info, I will without a doubt have the oil lines looked at (I might even do that myself).