Sunday, Dec 25, 2005 at 19:42
Hi Para - Black from the exhaust is generally soot ( carbon particles) - a byproduct of combustion of diesel fuel, as you probably know.
In the ideal engine, the mixture of diesel and oxygen from the air, at the correct pressure/Temp, will result in CO/CO2, and no carbon. But no engine is perfect.
Being new, it may take some time (varies) when the rings and
bore 'bed' in.
(For my 4.2 TD Patrol, they say it is up to 70,000 klms before fully beded.)
During this time, the fuel burn may not be completely up to specs, and some oil may bypass the rings and be burnt in the combustion chamber, increasing the carbon in the exhaust. In modern engines, I would think this minimal.
During acceleration, or under load (up
hill towing a load), the extra fuel load needed results in greater percentage of carbon = black out the exhaust.
So - If under load, it is unavoidable - simply large amounts of fuel (with insufficent oxygen) being burnt by the engine = carbon.
When not under load, I would not expect to see any black smoke.
Obviously a mechanical fault with the engine may lead to sump oil being burnt = black exhaust.
If the injectors are worn, the fuel may not be atomised properly, resulting in a poor burn = carbon rather than CO or CO2.
.Hope this helps..............regards.
AnswerID:
145554
Follow Up By: hl - Sunday, Dec 25, 2005 at 21:51
Sunday, Dec 25, 2005 at 21:51
Rule of thumb with a diesel:
If it's blue smoke, it's stuffed
If it's black smoke, it's over fueling or the injectors need doing.
None of this would apply to a new engine.
The 3.0TD is electronically controlled, and there should be no black smoke at all, however, as I said in my previous post, if you nearly stall it or labour it, you will see smoke.
(and I'd like to see an engine that will take 70,000k's to "bed in")
Cheers
FollowupID:
399087
Follow Up By: Truckster (Vic) - Sunday, Dec 25, 2005 at 23:05
Sunday, Dec 25, 2005 at 23:05
>> For my 4.2 TD Patrol, they say it is up to 70,000 klms before fully beded
yea numerous people are saying that they feel it losen up at about 40-50,000klms and it goes better, and drinks less.
FollowupID:
399092
Follow Up By: Exploder - Monday, Dec 26, 2005 at 00:38
Monday, Dec 26, 2005 at 00:38
Well they say the Ford Powerstroke Diesel can take up to 10,000
Miles so 16,000k’s to be fully run in. If they are leaving a new diesel to idle extensively or using it as a daily driver without putting some load on the engine in the first 1-2 thousand k’s then I could see it taking a long time to break in, 50,000k’s maybe.
As a contrast to that a lot of Modern petrol engines take as little as 300k to be run in, which is why it’s so important to break the engine in right from the first drive.
FollowupID:
399102