Black smoke / White smoke

[Harry]

:blowup: I own a 2000 DX patrol which has a few issues. Driving home from the bush yesterday car started blowing black smoke and she lost power. Car is not overheating or using oil. When I started the car in the morning lots of white smoke. Any help would be great! I thought it might be the turbo so I started removing from spare car and cannot remove the banjo bolt for the oil supply that is under the turbo. Does anyone know what size socket is required to remove it? I have unplugged the sensor but can not remove from banjo bolt either. Fumbling around please help.

[sme]

sme here, same thing happened to me with my 98 GU diesel patrol about 12 months ago...problem turned out to be unleaded fuel in tank instead of diesel. Completely drained tank and purged all lines, replaced fuel filters, primed and wallah it lives. No other problems and have done some 10000 klms since.

[Finly Owner]

My guess is injectors need servicing.

[Harry]

Hi guys thanks for the reply's. I have checked and are 100% positive the car has diesel fuel. I was abit disappointed as this would have been a quick fix. Started the car and let idle for a few minutes the white smoke seemed to ease up so decided to give her a few rev's. At about 2000rpm she started spewing out lots of smoke so turned her off and I removed the inlet pipe from the turbo into the intercooler only to find lots of oil. Thought I must have done a oil seal in the turbo. I removed the turbo to find it very broken. I will change out the intercooler for a clean spare from a 2004 model however I have noticed that the turbo's are different. Does anyone know if they can be modified or changed as the 2000 model has extra piping and banjo bolts. This would save me from puchasing a new one as it would take atleast 10 days to get to the Eylandt. I love living remote. Thanks for the reply's and everyone have a Happy New Year.

[Harry]

Hopefully the injectors/injector pump are ok because I have no idea how to service them or get them done up here.

[YNOT]

If your engine is a TD42T then there are differences between earlier and later models. The earlier models the got water cooled turbos which would explain the 2 extra connections. You will need to swap the thermostat/top hose housings and block the other connection to fit the non water cooled turbo.

Tony

[Harry]

The egine is a 3ltr zd30. Is it still possible to modify?

[YNOT]

If both engines are ZD30 DI motors then it most likely is possible, I've never done it myself. You will need to block the coolant feed and drain connections.

Tony

[Harry]

I have done the modifications and blanked off the coolant pipes. The car is running and has regained it's power however it is still blowing white smoke. Also the engine light is now staying on??? The car is not over heating, flushed and changed coolant and oil. Seems to sound abit tinny unitl higher in the rev range. Not sure, hopefully the smoke is just residual and will burn off eventually. Any idea's would be welcomed.
Harry

[YNOT]

I would be cleaning and testing the MAF sensor, the thread below explains it;
http://www.nissanpatrol.com.au/forums/showthread.php?597-Checking-and-cleaning-MAF-sensors&highlight=cleaning+sensors

Also check engine fault codes;
http://www.nissanpatrol.com.au/forums/showthread.php?595-Reading-and-erasing-GU-Patrol-fault-codes&highlight=fault+codes

If you don't already have a pyro (exhaust gas temperature) gauge, I would fit one ASAP. If your engine is over fueling your exhaust temps will be excessive which could lead to engine failure. Fitting a boost gauge would be a good idea also.

Tony

[Dmitrijs_Riga]

Hi. Maybe you know this, but here is a good explanation of black/white/blue smoke and with good explantion
http://www.dieselsmoke.com.au/

[Harry]

Thanks for the posts fella's. I have cracked the code (maybe). As I had taken the turbo out of my broken 2004 model (my fault) I had forgotten that it had a Safari mod chip. This obviously had something to do with the engine light on in the dash and the poor idle and lack of power on initial take off because as soon as I plugged it in all the problems/symptoms went away. How is that possible as it had never been in the 2000 model patrol before? Also the smoke has gone so hopefully that was just the excess oil from the turbo.

[scrawn]

i had a diesel hilux that had white smoke all the time

found out it was advanced timing that caused that

[jado]

lucky for u, those type of stories normally end up in big $$$'s

[Milik607]

A friend solved a similar problem, the result was that the injection pump gave a great benefit by itself, had to change the control unit.

[GU4u]

Hey Ynot how are pyro (exhaust gas temperature) gauge fitted and how do they work? I would have thought if your engine was over fueling it would run cooler. If you got a petrol engine and it runs lean then temp goes up, so diesels aren't like petrol engines?
am sort of lost have not had a lot to do with the old black guts!

Cheers
Scotty

[YNOT]

A pyro gauge has a thermocouple placed in the exhaust gases as close to the cylinder head as possible for accuracy. A lot of people myself included choose to fit the thermocouple immedietly after the turbo so if anything does happen the thermocouple it won't damage the turbo. The rule of thumb is add 100 degrees to the post-turbo temps to get pre-turbo temp.

Diesels are the opposite of petrols when it comes to mixtures, an overfueled diesel will run hot.
It's interesting driving a turbo diesel with boost and pyro gauges for the first time and seeing what is happening in your engine. Lets say your cruising at 60km/h in 4th gear, about 1800rpm. Put your foot down to accelerate up to 100km/h, the boost gauge will come up very quickly (especially if you have a big exhaust fitted) but the pyro will lag behind and be a lot slower to rise. You will find you can move the needle on the pyro by lifting and pushing the accelerator. If your foot is flat to the floor the turbo will be on full boost (7psi standard) and the EGT's will rise to 500-550 if you hold you foot down for a while, but lift your foot slightly and the EGT's will start to drop without the boost gauge moving.
At other times under heavy load (climbing a long hill) you will often find that although you have the torque to maintain speed on that hill in 4th gear, the EGT's will be lower by dropping down to third and using less throttle to maintain the same speed.

Tony

[Finly Owner]

A pyro gauge has a thermocouple placed in the exhaust gases as close to the cylinder head as possible for accuracy. A lot of people myself included choose to fit the thermocouple immedietly after the turbo so if anything does happen the thermocouple it won't damage the turbo. The rule of thumb is add 100 degrees to the post-turbo temps to get pre-turbo temp.

Diesels are the opposite of petrols when it comes to mixtures, an overfueled diesel will run hot.
It's interesting driving a turbo diesel with boost and pyro gauges for the first time and seeing what is happening in your engine. Lets say your cruising at 60km/h in 4th gear, about 1800rpm. Put your foot down to accelerate up to 100km/h, the boost gauge will come up very quickly (especially if you have a big exhaust fitted) but the pyro will lag behind and be a lot slower to rise. You will find you can move the needle on the pyro by lifting and pushing the accelerator. If your foot is flat to the floor the turbo will be on full boost (7psi standard) and the EGT's will rise to 500-550 if you hold you foot down for a while, but lift your foot slightly and the EGT's will start to drop without the boost gauge moving.
At other times under heavy load (climbing a long hill) you will often find that although you have the torque to maintain speed on that hill in 4th gear, the EGT's will be lower by dropping down to third and using less throttle to maintain the same speed.

Tony

I was going to ask what are EGT's but I know E xhaust G as T emperatures

derr Tim

[GU4u]

Thanks Ynot

[philmar]

Low compression will also create white smoke. I don't know if particles can slip through the intercooler, but you mentioned the turbo was "very broken", I assume by this
that the veins were probably broken. It doesn't take much of a piece to do a lot of damage.
White smoke on start up that dissipates can be caused by a faulty glow system or plug, causing low heat in one or more cylinders.

Phil.

[tkn]

Diesels are the opposite of petrols when it comes to mixtures, an overfueled diesel will run hot.
It's interesting driving a turbo diesel with boost and pyro gauges for the first time and seeing what is happening in your engine. Lets say your cruising at 60km/h in 4th gear, about 1800rpm. Put your foot down to accelerate up to 100km/h, the boost gauge will come up very quickly (especially if you have a big exhaust fitted) but the pyro will lag behind and be a lot slower to rise. You will find you can move the needle on the pyro by lifting and pushing the accelerator. If your foot is flat to the floor the turbo will be on full boost (7psi standard) and the EGT's will rise to 500-550 if you hold you foot down for a while, but lift your foot slightly and the EGT's will start to drop without the boost gauge moving.
At other times under heavy load (climbing a long hill) you will often find that although you have the torque to maintain speed on that hill in 4th gear, the EGT's will be lower by dropping down to third and using less throttle to maintain the same speed.

Tony

Thanks for the explanation of the relationship between EGTs, boost pressures and throttle openings.

If I have really understood what you said –

1. EGTs increase because of unburnt diesel and amounts of unburnt diesel are created by “more accelerator” relative to engine revs, instead of changing down a gear.
2. EGTs (i.e. unburnt diesel) are also increased by an injector pump which is incorrectly adjusted and supply too much diesel relative to throttle openings.
3. The result in each scenario is an overheated turbo, black smoke from the exhaust, a sooty exhaust and a very hot dump pipe.

Please let me know if I have got any of that wrong.

I don’t have a boost gauge or a thermocouple fitted, but found that if I leaned off the injector pump too much (which was about 1/10 of a turn of the adjustor screw) i got a lack of power, a hot engine (i.e. looking at the coolant temperature gauge - the turbo is oil cooled) and a hot dump pipe.
Anyway, to correct that “problem” I overcompensated so that I ended up with black smoke with acceleration, but coolant temperatures looked more comfortable, even though the dump pipe still seemed to get pretty hot.
With my third adjustment (about 1/20 of a turn the other way) I think I’ve got it almost right – less accelerator pedal for the same or more power, coolant temperature that rises when climbing hills (I’ll now be using 4th gear a little more) and a dump pipe that is less like a roasting spit.

I’m uncomfortable with the variation in coolant temperatures (rises from about 1/3 to 1/2) as my reading of it is that there is a peak in the engine operating temperature that is not fully reflected in the temperature gauge movement. That said, it does not appear to matter much whether it is a hot day or a cool day, the coolant temperatures seem to be roughly the same.

I would appreciate any additional info.

[YNOT]

If I have really understood what you said –

1. EGTs increase because of unburnt diesel and amounts of unburnt diesel are created by “more accelerator” relative to engine revs, instead of changing down a gear. Diesels engines are an excess air engine, as far as airflow into the intake is concerned they are at full throttle all the time, the power is throttled by accelerator position and therefore quantity of fuel injected. The more fuel that is injected the hotter the combustion gets. As with any fire if you add more fuel than what the oxygen can support you will end up with unburnt fuel, in a diesel engine the unburnt fuel will continue to burn as it exits the cylinder past the exhaust valve and into the turbo (where fitted). Excessively high exhaust gas temperatures can melt pistons and valves, and damage turbos.

2. EGTs (i.e. unburnt diesel) are also increased by an injector pump which is incorrectly adjusted and supply too much diesel relative to throttle openings. A injector pump is incorrectly adjusted if it is supplying more fuel than what the oxygen in the cylider can support.

3. The result in each scenario is an overheated turbo, black smoke from the exhaust, a sooty exhaust and a very hot dump pipe. And possibly melted pistons and valves.
Please let me know if I have got any of that wrong.

Another thing to consider is your injectors. If they are not atomising the fuel properly the fuel will be slow burning and raising EGT's even though the actual quantity of fuel injected can be supported by the oxygen in the cylinder.It's important to make sure the basics are correct before you start doing any tuning, so valve clearances, injectors, injector pump, pump timing, boost etc.

I don’t have a boost gauge or a thermocouple fitted, but found that if I leaned off the injector pump too much (which was about 1/10 of a turn of the adjustor screw) i got a lack of power, a hot engine (i.e. looking at the coolant temperature gauge - the turbo is oil cooled) and a hot dump pipe.
Anyway, to correct that “problem” I overcompensated so that I ended up with black smoke with acceleration, but coolant temperatures looked more comfortable, even though the dump pipe still seemed to get pretty hot.
With my third adjustment (about 1/20 of a turn the other way) I think I’ve got it almost right – less accelerator pedal for the same or more power, coolant temperature that rises when climbing hills (I’ll now be using 4th gear a little more) and a dump pipe that is less like a roasting spit. I would not recommend setting the injector pump by engine temperature, the engine temp guage is far too slow reacting and no where near accurate enough. Do yourself a favour and fit boost and pyro gauges ASAP.

I’m uncomfortable with the variation in coolant temperatures (rises from about 1/3 to 1/2) as my reading of it is that there is a peak in the engine operating temperature that is not fully reflected in the temperature gauge movement. That said, it does not appear to matter much whether it is a hot day or a cool day, the coolant temperatures seem to be roughly the same. It might be time to do some cooling system maintanence.