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Technical Oil in Exhaust

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Technical Oil in Exhaust

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earl34

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Aug 19, 2014
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Re: 2004 244 2.8JTD

Left the engine idling for 30-40 minutes and noticed oil leaking from an exhaust joint. No smoke even when i revved the engine.
Engine temp was around 50C, oil pressure was 35psi.
10/40 semi synthetic oil.

Any ideas what has caused the oil in exhaust?

Many thanks.
 
As above re exhaust.
What temp does your unit run at on the road? To be only at 50° after half an hour idling suggests that the thermostat might be shot. Should run a lot hotter than that - around 85 - 90° is typical. If you are running at 50-60°, you will be losing quite a lot in economy and fuel pollutant of the engine oil will not be evaporating out. Not good....
 
Thanks for your replies.
I checked the exhaust again for oil but it's dry.:confused:

i'll take a look at the thermostat.
 
ecunotemu said:
Are you sure its not soot mixed with condensation?
Click to expand...

That's what it was.

I checked the thermostat and it's working fine.
I've seen forum posts that indicate that the 2.8JTD runs very cool but no solutions posted.
 
earl34 said:
That's what it was.

I checked the thermostat and it's working fine.
I've seen forum posts that indicate that the 2.8JTD runs very cool but no solutions posted.
Click to expand...

What do you mean by "checked the thermostat". What temp is the motor running at on highway? All diesels need to run above 80°C to be efficient and only the thermostat can control this.
 
oigle said:
What do you mean by "checked the thermostat". What temp is the motor running at on highway? All diesels need to run above 80°C to be efficient and only the thermostat can control this.
Click to expand...

I removed the thermostat, put it in a pan of water and heated it up on a stove. It opened just before the water boiled.
The motor runs at 55-60 degrees C.
 
earl34 said:
I removed the thermostat, put it in a pan of water and heated it up on a stove. It opened just before the water boiled.
The motor runs at 55-60 degrees C.
Click to expand...

Well, if that was my thermostat, I'd replace it quicksmart. 55-60°C is no good. Visibly seeing a thermo open isn't accurate. You need to force it open and insert a piece of strong thin cotton through gap. Let it cool again and hang it in cold water. Heat water with a thermometer in it and see what temp the cotton pulls loose. Never place thermo straight into hot water - it will wreck it.
Regardless of above test, if motor running at 55°C, it needs replacing.
Is gauge reading accurately? What temp is stamped on thermostat?
 
Last edited:
earl34 said:
I removed the thermostat, put it in a pan of water and heated it up on a stove. It opened just before the water boiled.
The motor runs at 55-60 degrees C.
Click to expand...

Did you think about these two statements long enough?

If your thermostat really opens near the boiling point (like it should), the engine simply cannot run at 55-60 C. unless you are above the polar circle and have a giant cabin heater installed. It would mean that you can at any time put your hands on the radiator because it remains completely cold!
 
Yes, it is puzzling.
I'll change the thermostat and see if it improves.
Thanks for all your advice. (y)
 
Did you measure 55/60 after driving, the 2.8 takes about 20km of driving to come up to full temperature, idling it never reaches full temperature.

What did you measure the temperature with, if you're using an infrared thermometer then you should check the hoses / plastic tank (radiator ends) as reflective surfaces like radiator core have low emissivity and can give a lower reading.
 
ecunotemu said:
Did you measure 55/60 after driving, the 2.8 takes about 20km of driving to come up to full temperature, idling it never reaches full temperature.

What did you measure the temperature with, if you're using an infrared thermometer then you should check the hoses / plastic tank (radiator ends) as reflective surfaces like radiator core have low emissivity and can give a lower reading.
Click to expand...

Yes, i drove about 50km.
I have a Durite mechanical gauge with a sender in the top hose. I double checked with a digital sensor probe. When i checked the gauge showed 60 the digital probe 62.
I can only think that the 'stat is opening early. I'll swap it and post the results.
 
CDK said:
Did you think about these two statements long enough?

If your thermostat really opens near the boiling point (like it should), the engine simply cannot run at 55-60 C. unless you are above the polar circle and have a giant cabin heater installed. It would mean that you can at any time put your hands on the radiator because it remains completely cold!
Click to expand...

:rolleyes:
The gauge sender is in the top hose, after the 'stat.
The 'stat is closed and the coolant short circuits the cooling system until the coolant temperature reaches approx. 80 degrees C. When the 'stat opens coolant at 80 mixes with coolant that is a lot less than 80 and circulates around the rad etc further reducing the coolant temperature.
The rad doesn't remain completely cold, it remains at 55-60 because the cycle of heating and cooling with the 'stat opening and closing continues.

I changed the the 'stat, stamped 82 degrees, with a new Gates item also stamped 82. Made no difference at all.

So, I fixed a blind over 1/4 of the rad and achieved close to 70 degrees running temp. after 20km.
This may be the way forward. Unless anyone knows better...;)
 
earl34 said:
:rolleyes:
The gauge sender is in the top hose, after the 'stat.
The 'stat is closed and the coolant short circuits the cooling system until the coolant temperature reaches approx. 80 degrees C. When the 'stat opens coolant at 80 mixes with coolant that is a lot less than 80 and circulates around the rad etc further reducing the coolant temperature.
The rad doesn't remain completely cold, it remains at 55-60 because the cycle of heating and cooling with the 'stat opening and closing continues.

I changed the the 'stat, stamped 82 degrees, with a new Gates item also stamped 82. Made no difference at all.

So, I fixed a blind over 1/4 of the rad and achieved close to 70 degrees running temp. after 20km.
This may be the way forward. Unless anyone knows better...;)
Click to expand...

I have an election poster over mine in the winter don't need it in the summer though, do you hear your fan running regularly?
 
ecunotemu said:
I have an election poster over mine in the winter don't need it in the summer though, do you hear your fan running regularly?
Click to expand...

No, to my knowledge the fan has only come on once.
I had to free up the second fan as it was seized so i guess it didn't get much use.
What amount of rad do you cover in the winter?
 
earl34 said:
:rolleyes:
The gauge sender is in the top hose, after the 'stat.
The 'stat is closed and the coolant short circuits the cooling system until the coolant temperature reaches approx. 80 degrees C. When the 'stat opens coolant at 80 mixes with coolant that is a lot less than 80 and circulates around the rad etc further reducing the coolant temperature.
The rad doesn't remain completely cold, it remains at 55-60 because the cycle of heating and cooling with the 'stat opening and closing continues.

I changed the the 'stat, stamped 82 degrees, with a new Gates item also stamped 82. Made no difference at all.

So, I fixed a blind over 1/4 of the rad and achieved close to 70 degrees running temp. after 20km.
This may be the way forward. Unless anyone knows better...;)
Click to expand...

You have just diagnosed the issue yourself, unwittingly. Your temp sender is in the wrong place. It is not indicating the running temp of the motor. The temp sender is normally positioned within the area prior to the thermostat and should record the temp in the head, not after it has mixed with water after the thermostat.
It doesn't matter what temp the rad is running at, so long as the water in the head/block are at the required temp of 82°C
 
I thought that as the sender is only 150mm from the 'stat and before the rad, the coolant would be warmer.
Also, the dash gauge never went over 1/4 so i thought there was an issue.
However, I should have changed the 'stat in the first place.
Even though the original was OK it would have confirmed that all was well with the engine temp. and saved me a lot of grief.
 
Still sounds cold to me. Did you use the radiator from the JTD or the original?
 
ecunotemu said:
Still sounds cold to me. Did you use the radiator from the JTD or the original?
Click to expand...

I'm surprised the coolant can reduce temperature by 20 degrees in 150mm.:confused:
I have a new rad fitted, one for a 2.5TD Ducato/J5.
It's the same size as the JTD rad but has the mounting plates required for the J5. The JTD/J5 rad fans even share the same mounting points.
 
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