Black Smoke after long tick over
#1
Black Smoke after long tick over
Hi Folks
I bought a 97 Disco 300TDi 140k miles, two weeks ago (my first Landy). My first impressions are that all seems OK apart from a slow puncture on near side front - not a problem, and the rev counter is a bit jumpy.
The seller showed/gave me invoices for a new cam belt at 120k miles and head gasket & skim around the same time.
While at work I took it to a local car cleaners yesterday for a full valet, and when I came to pick it up I noticed it was very smokey; they had the engine running with the heaters on - probably for some time. When I pulled away, I noticed a serious amount of smoke churning out of the back (choking the pedestrians!) and was faced with a 40 mile commute home, I drove cautiously looking for somewhere to pull over but the smoke was starting to decrease; by the time I had got to the motorway (aprox 2 miles) it was running clear; so I was thinking this may be somethng to do with them steam cleaning the engine. By the time I got home, it was running fine, oil levels seem OK.
Next moring I did the return commute, with no problems, however I got stuck in a major trafic jam towards the end of the journey which left me sitting still on tick over for aprox 2 hours; throughout this time I was nervous of yesterdays problem but due to freezing weather kept it running with the heaters on. Eventually the trafic started to clear, and again as I was pulling away I had masses of black smoke pouring out of the back, which again cleared after about a mile or so. Later today, my journey home went OK, and at idle when arrived home there is no smoke to see.
This problem seems to be related to long times at tickover and standstill.
Any ideas?
Thanks in advance
I bought a 97 Disco 300TDi 140k miles, two weeks ago (my first Landy). My first impressions are that all seems OK apart from a slow puncture on near side front - not a problem, and the rev counter is a bit jumpy.
The seller showed/gave me invoices for a new cam belt at 120k miles and head gasket & skim around the same time.
While at work I took it to a local car cleaners yesterday for a full valet, and when I came to pick it up I noticed it was very smokey; they had the engine running with the heaters on - probably for some time. When I pulled away, I noticed a serious amount of smoke churning out of the back (choking the pedestrians!) and was faced with a 40 mile commute home, I drove cautiously looking for somewhere to pull over but the smoke was starting to decrease; by the time I had got to the motorway (aprox 2 miles) it was running clear; so I was thinking this may be somethng to do with them steam cleaning the engine. By the time I got home, it was running fine, oil levels seem OK.
Next moring I did the return commute, with no problems, however I got stuck in a major trafic jam towards the end of the journey which left me sitting still on tick over for aprox 2 hours; throughout this time I was nervous of yesterdays problem but due to freezing weather kept it running with the heaters on. Eventually the trafic started to clear, and again as I was pulling away I had masses of black smoke pouring out of the back, which again cleared after about a mile or so. Later today, my journey home went OK, and at idle when arrived home there is no smoke to see.
This problem seems to be related to long times at tickover and standstill.
Any ideas?
Thanks in advance
#2
Join Date: May 2009
Location: North Carolina Coast
Posts: 1,348
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First off where are you from? I'm guessing UK, and Tick I'm assuming means Idle, for us yanks. I'm not too familiar with deisels but could it be that it is running cold, when deisels are cold they smoke alot. maybe you have a thermostat stuck open and when you are idleing for a long period in the extreme cold its cooling off too much. just a wild guess.
#3
Hi Tweakrover
Appologies, yes I'm in the UK and yes tick over to us normally means idling.
This idea makes sense, although the amount of smoke it produces is really exessive and it doesn't smoke like that from cold start.
I don't see any smoke until a couple of hours have gone by, the engine is warm by then and the guage is reading perfect. Also I do not see this problem when driving normally. It only happens after a long period of idling at standstill, I had gone several days doing the same commute and never saw any smoke.
Now thinking about this, I do remember noticing the temp guage drop (cooler) when sitting in the traffic today, I was keeping an eye on this checking it doesn't get too hot.
I'm still concerned about the amount of smoke though.
Appreciate your advice, it's something to check, many thanks.
This idea makes sense, although the amount of smoke it produces is really exessive and it doesn't smoke like that from cold start.
I don't see any smoke until a couple of hours have gone by, the engine is warm by then and the guage is reading perfect. Also I do not see this problem when driving normally. It only happens after a long period of idling at standstill, I had gone several days doing the same commute and never saw any smoke.
Now thinking about this, I do remember noticing the temp guage drop (cooler) when sitting in the traffic today, I was keeping an eye on this checking it doesn't get too hot.
I'm still concerned about the amount of smoke though.
Appreciate your advice, it's something to check, many thanks.
#5
Join Date: Mar 2010
Location: Pittsburgh PA suburbs.
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I totally avoid anything like steam cleaning or high pressure water spray under the hood. There are too many things that can go wrong when connections get wet.
I don't know about the 300TDI but on my 97 4.0 V8, the ECU is especially vernable to getting wet and then they run terribly if at all!
I also don't turn it over to just anyone to mess with without my being right there. Too many things can get damaged by well-meaning but not well informed people.
I don't know about the 300TDI but on my 97 4.0 V8, the ECU is especially vernable to getting wet and then they run terribly if at all!
I also don't turn it over to just anyone to mess with without my being right there. Too many things can get damaged by well-meaning but not well informed people.
#7
Ok, this is coming from a truck driver with lots of diesel idling experience...when you idle a diesel the engine it cools off.
Diesels run very efficiently and do not run as hot because of this. They turn more of the fuel into actual power than a gas (petrol) engine does.
A gas engine is great at producing heat, poor at burning fuel.
What happens with a diesel that is idling for a long time is as the engine cools off the cylinders start to load up with unburnt fuel, as soon as you increase engine RPM then all of that fuel is burnt and because a cold engine is not as efficient as a hot engine the fuel is not burnt completely and it smokes. (you cannot flood a diesel engine, it will burn as much fuel as you can dump into it, the more fuel the more it smokes)
Once it gets warm out this will not happen.
You need to do two things.
1-replace the thermostat to make sure that it is in good working order and of the correct temp.
2-get a "radiator muff" for your truck.
http://www.roversnorth.com/store/p-5...er-90-110.aspx
What it does is it restricts the amount of air that passes past the radiator to keep it from cooling the engine to much.
This aids in engine warm up, keeps the engine warm after shut down and keeps it warm while idling.
In the winter you will get tons of heat and the engine will not overheat because once you start moving there will be enough air passing through the radiator to keep the engine cool.
I used to make my own with a piece of cardboard, I would take a box and cut it to half the height of my radiator but just as long and then stick it between the grill and the radiator, then I would throw it away come spring.
It worked great.
While sleeping in my truck I would still have some heat.
But after idling for only a hour a diesel that has been cruising down the expressway for 3 hours would show stone cold on the temp gauge, start driving and there would be so much smoke you would think I was laying a smoke cloud to hide from the German's.
So I used the throttle lock to hold the idle at 1200 rpm and I would have heat as long as I wanted.
You may need to go to the dealer to get a radiator muff for your Discovery.
Or make your own.
Diesels run very efficiently and do not run as hot because of this. They turn more of the fuel into actual power than a gas (petrol) engine does.
A gas engine is great at producing heat, poor at burning fuel.
What happens with a diesel that is idling for a long time is as the engine cools off the cylinders start to load up with unburnt fuel, as soon as you increase engine RPM then all of that fuel is burnt and because a cold engine is not as efficient as a hot engine the fuel is not burnt completely and it smokes. (you cannot flood a diesel engine, it will burn as much fuel as you can dump into it, the more fuel the more it smokes)
Once it gets warm out this will not happen.
You need to do two things.
1-replace the thermostat to make sure that it is in good working order and of the correct temp.
2-get a "radiator muff" for your truck.
http://www.roversnorth.com/store/p-5...er-90-110.aspx
What it does is it restricts the amount of air that passes past the radiator to keep it from cooling the engine to much.
This aids in engine warm up, keeps the engine warm after shut down and keeps it warm while idling.
In the winter you will get tons of heat and the engine will not overheat because once you start moving there will be enough air passing through the radiator to keep the engine cool.
I used to make my own with a piece of cardboard, I would take a box and cut it to half the height of my radiator but just as long and then stick it between the grill and the radiator, then I would throw it away come spring.
It worked great.
While sleeping in my truck I would still have some heat.
But after idling for only a hour a diesel that has been cruising down the expressway for 3 hours would show stone cold on the temp gauge, start driving and there would be so much smoke you would think I was laying a smoke cloud to hide from the German's.
So I used the throttle lock to hold the idle at 1200 rpm and I would have heat as long as I wanted.
You may need to go to the dealer to get a radiator muff for your Discovery.
Or make your own.
#9
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