1979 240D excessive oil consumption

Okay I've got a 1979 240d that has plenty of power (for a 240D), runs smoothly and has none of the usual outward signs of low compression. Always starts on cold days, no oil residue at the tail pipe and like I said pretty
decent power. I have changed my valve cover gasket and oil filler. But I can't figure it out. I alway assumed that if a car has blowby I should be able to see some signs at the tail pipe. Any thoughts???
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
how much oil does it use per thousand miles
?
the case, minus a few cans!
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
So how much oil are you losing vs miles?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

About a quart every 100 miles. It's pretty excessive.....
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
At the tail pipe you won't see any evidence of the engine burning oil. It's the blue smoke screen that you leave behind that's telling.
If the diesel starts well in the cold and has reasonable power - all 68 HP - then the rings and compression may be OK. You didn't say how many miles are on this engine, if over 250K it may well be worn and the oil burning is a sign of that.
You've evidently tried to fix some oil leaks with new gaskets. This engine has only a few leak sites, valve cover, bottom cover and the crankshaft seals - front and back. The vacuum pump on the front of the engine is another possibility.
Blow by is from combustion by-passing the worn rings and creating pressure inside the engine that forces oil to leak from the above mentioned sites.
On the top of the valve cover is a hose to carry the crankcase fumes to the intake manifold for disposal. It could be that this hose is clogged and/or that the screen inside the valve cover is so dirty that oil that should be drained off is being forced into the intake manifold and consumed. This is more possible if the engine runs too cold - without a 80 degree C. thermostat.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
The engine has about 350K+ on it, but it doesn't leave the telltale blue "smoke screen" that is evident of worn rings either. I will look at the thermostat, and check the screen too. I know I'm tilting at windmills hoping for a cheap fix when none is available, but I can hope......
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 2004-11-13 22:20:54 -0800, "Mister Tawny the Talking Tiger"

Is the car leaving a visible puddle of oil when parked? 100miles per quart is a lot of oil consumption, especially if you aren't seeing blue smoke.
Marty
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Hope is about all that's left after 350K miles.
Look for a used engine if the rest of the car is good.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
i had one leak oil out the filter lid after the oil changed
the case, minus a few cans!
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
I'm not leaving any puddles that I can see. It is a quandry. I don't see how a car can burn that much oil and not have a white cloud and leave a noticable residue around the rear end. Any other thoughts? I will check the oil filter too!
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
clean it up with GUNK spray cleaner as best you can. let dry then start it up.
look for any leaks. shut it down after 20 mins. try to put a large box under the car & check it for spots after a few hours.
if your burning a QT every 100 miles there ain't a BUG within miles of your home
the case, minus a few cans!
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Or use a pressure washer and really wash that engine down with detergent.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
O pleeze. The man's loosing a quart every hundred miles. One quart of oil is sufficient to cover the entire car; there's no need to look under the carpets or in the trunk or even wash the engine. A diesel normally burns oil-fuel oil- without (much) smoke. Why should lube oil be different?
Chas Hurst

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Tue, 16 Nov 2004 23:40:27 -0500, "Chas Hurst" wrote:

Could it be that this car is blowing pressure past the rings, pressurizing the sump and blowing oil out the breather (into the air filter usually), this would then be drawn into the engine and burnt (I.E. vanish). This may explain a loss of oil with no visible puddles. It would of course be worse when the car was cold, so rough idle when cold maybe. A little smokier when cold too perhaps. But Chas is right isn't he, if this engine can burn diesel oil without smoking, why can't it burn slightly thicker (and clean too if it's having a litre of oil added every 100 miles) oil with very little smoke.
If this type of scenario is plausible, then it could also be a head gasket leaking pressure from one or more cylinders into an oilway; thus pressurizing the sump that way?
Don't shout at me, it's just a thought! Mike
--
W126 300SE
W115 220/8
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I'd look underneath the engine for visible signs of leaking. Maybe a main seal that leaks a lot more when the engine is running so that the oil is being left on the road?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Related Threads

    Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.