Diesel smoke questions? Read this first! (3 Viewers)

[TxEddie1111]

smoke

Opinions and facts desired.
I live in Houston (200' altitude) and my H diesel smokes just a bit on warm up (2-3 minutes, whitish).
I just hauled it up to Colorado to about 9000' and it continually smokes (whitish) although it reduces after warmup and really puffs (black) unter a load. I also hear knocking
I've never heard. Is this just the thinner air? can the engine be adjusted to resolve this? is this a simple thing? does it hurt to drive it this way?

Thanks for all the knowledge....

Cheers,

Eddie

 

[amaurer]

Opinions and facts desired.
I live in Houston (200' altitude) and my H diesel smokes just a bit on warm up (2-3 minutes, whitish).
I just hauled it up to Colorado to about 9000' and it continually smokes (whitish) although it reduces after warmup and really puffs (black) unter a load. I also hear knocking
I've never heard. Is this just the thinner air? can the engine be adjusted to resolve this? is this a simple thing? does it hurt to drive it this way?

Thanks for all the knowledge....

Cheers,

Eddie

Black smoke is normal at attitude. White smoke is a problem, prossibly low compression.

 

[TxEddie1111]

Thanks!

So, why would it just start smoking (white) on the first run at alitude when it wasn't happening at 200'?? After it warmed up it would not smoke.....(is white smoke always a compression problem-indicator?)

 

[amaurer]

Thanks!

So, why would it just start smoking (white) on the first run at alitude when it wasn't happening at 200'??

Because altitude lowers the effective compression of the engine. If spec at sea level is 420psi (or thereabouts) then at 9000' even a perfect engine would only produce about 300psi (which, you'll note, is approaching the level at which a diesel won't even run).

So if you have a low cylinder, say 350psi, in Houston you might see some white smoke until the truck is warm. If you bring that cylinder to 9000' then its compression would only be 250psi... at which point even warming it up probably won't stop the smoke.

 

[TxEddie1111]

makes sense.... is it harmful to run the engine for a week? (other than the annoying smoke).

Finally, I suppose a rebuild is in the future???

 

[amaurer]

makes sense.... is it harmful to run the engine for a week? (other than the annoying smoke).

Finally, I suppose a rebuild is in the future???

Smoke is safe to run on, probably. The knock is another question.

Rebuild is a "maybe"... check compression first.

 

[Turbo45]

cut the oil filter if you suspect engine troubles ......... it tells you if the bottom end is likey ok or not

 

[canucksafari]

Before assuming the worst, read this whole smoke thread: https://forum.ih8mud.com/diesel-tech-24-volts-systems/273850-diesel-smoke-questions-read-first.html.

All naturally aspirated diesels smoke black at high altitude like that. You can't drive it like it is at 200'. Easy on the skinny pedal and gear down.

Your white smoke could be many things... as simple as a clogged filter or a leaky primer or a leaking fuel line (sucking air in). Given you say it feels like it is knocking, my bet would be one of these easier fixes rather than compression.

My recommendation is you read the thread the thread and eliminate the cheap and easy fixes before looking at the more complicated and costly fixes. Although, it never hurts to do a compression test to have an idea of the condition of your engine.

 

[cruiser_guy]

Back off when the black smoke starts. On a diesel black smoke = heat and that's bad news. You'll be gearing down and taking your time, get used to it or get turbo'd

Moving/amalgamating this with the "Smoke" thread in the stickies.

 

[canucksafari]

Engine Australia's tech on diesel smoke: http://www.engineaustralia.com.au/seb/engine_seb/sb007.pdf

It's a good quick summary.

 

[aaark35]

well i have also got the smoke problem with 1hdt and after going through a manual i came across the boost compensator ,so guys need little suggestion regarding the boost compensator .... if any body has any information regarding this plz share bec this smoke is on my mind

 

[Leitrum3]

well i have also got the smoke problem with 1hdt and after going through a manual i came across the boost compensator ,so guys need little suggestion regarding the boost compensator .... if any body has any information regarding this plz share bec this smoke is on my mind

If you're looking to pick one up, try Akella, he gets them in occasionally for a good price. I picked one up from him recently for my 1HZ.

 

[dontblate]

400 cummins big cam smokin

First let me start off the history. This is a replacement engine and the shop had to replace some things in the heads because it smoked like all ----. Then something fell into the head so more shop work. Today it`s blowing blue smoke at idle and when I throttle it blows quite a bit. Backing a long ways ( dump truck ) while throttling it is constant and more visible as the smoke goes by the riders side window. Enough to bother me. The engine has been hot after the water pump went out. I noticed just a tad less oil pressure after that so I added LUCAS OIL TREATMENT and the pressure is very good now. I`m wondering if the injectors seals or whatever they had to replace before are the problem again. The first time fuel was getting in the oil pan, enough so I had to keep checking the oil level. The shop finnally said bring it in and they replaced some seals or guides. Needless to say after the experience there I never went back. Any help would be appreciated.

 

[mike]

There's been a lot of questions over the years about diesel smoke, and what the different colors mean. There have been some good data and input from different members.

Maybe the mods can look at diesel smoke FAQ.

Here is the main data from the NZ link, without the hyperlinks. I think it jives with what some of the more experienced and knowledgeable folks have mentioned. What do ya'll think.


SMOKE COLOUR

Basically there are 3 types of smoke emitted from a diesel engine: black, blue and white.

Black smoke:

Black smoke is the most common emitted from diesel engines and indicates incomplete combustion of the fuel. Black smoke causes can vary widely and include ..
· Incorrect fuel injection timing
· Dirty or worn fuel injectors
· Over fuelling
· Faulty turbocharger, or turbo lag
· Faulty or dirty exhaust gas recycling (EGR) system
· Incorrect valve clearance
· Incorrect fuel to air ratio
· Dirty or restricted air cleaner systems
· Over loading the engine
· Poor fuel quality
· Cool operating temperatures
· High altitude operation
· Excessive carbon build-up in combustion and exhaust spaces

Black smoke can occur across the entire operating range, but is usually worst under full power, or during the lag before the turbocharger boosts air supply to match the fuel usage such as in the early stages of acceleration and during gear changes. Moderate turbo lag smoke is acceptable; otherwise black smoke should be hardly visible in a correctly running engine.

Blue smoke:

Blue smoke is caused by engine lubricating oil burning. The oil can enter the combustion chamber from several sources including:

· Worn valve guides, or seals
· Cylinder &/or piston ring wear
· Cylinder glaze
· Piston ring sticking
· Incorrect grade of oil .. too thin and getting past rings, or valves guides
· Fuel dilution of the oil, making it too thin.

Blue smoke is often evident at cold start, which can reflect reduced oil control due to carbon fouling deposits around the piston rings and/or cylinder glaze. Blue smoke should not be evident at any stage.
An engine may burn oil without the evidence of blue smoke, because good compression burns oil quite cleanly, however, it is not acceptable for any new engine, or engine in good internal condition to burn large amounts of lubricating oil.

White smoke:

White smoke is caused by raw, un-burnt fuel passing into the exhaust stream. Common causes include:
· Incorrect fuel injection timing
· Defective fuel injectors
· Low cylinder compression

Low cylinder compression may be caused by leaking valves, sticking piston rings, ring wear, cylinder wear, or cylinder glaze. When white smoke occurs at cold start and then disappears as the engine warms up, the most common causes are fouling deposits around piston rings and/or cylinder glazing.
Continuous evidence of white smoke indicates a mechanical defect, or incorrect fuel timing.

Is there a easy fix for ---When white smoke occurs at cold start and then disappears as the engine warms up, the most common causes are fouling deposits around piston rings and/or cylinder glazing?

 

[ned kelly]

well i have also got the smoke problem with 1hdt and after going through a manual i came across the boost compensator ,so guys need little suggestion regarding the boost compensator .... if any body has any information regarding this plz share bec this smoke is on my mind

Hi i will try & help to explain how it works thinking you are talking about fuel pump boost comp, if you want to know if its working remove pipe that comes into top of pump blank with 5mm ball then run your car u should fell power loss its just a diaphragm that gets pushed down buy boost pressure, what colour smoke at what rev range + engine temp are u getting?

 

[ned kelly]

Hi iam new on site if anyone need advise on diesel motors problems just ask i have had loads of help off site & dont mind giving a bit back ive had 30 yrs of building diesel fuel systems & engine repairs on diesels

 

[Oldtoy74]

Hi Ned, not wanting to hijack thread as this is for smoke related issues, but I have slight hesitation around 13-1500rpm and it seems it less noticeable almost disappears on low tank of diesel, where should I start to investigate this annoying aspect of my 13bt, just for ref blows a little blue smoke on start up which clears up once moving, and no real abnormal white or black smoke, happy to take this to new thread if needed. Such is life

 

[ned kelly]

hi old toy just keep using it with the tank low for a few week if problem goes away, iam thinking fuel return fault or tank or is it the extra wieght fault let me know how u go its easier to monitor a fault before you remove parts.

 

[Clbeaty]

I've got a 1hdt transplant w/ auto tranny. I'm struggling to reduce black smoke. Turbo lag is definately part of the issue at low rpm but It still seems excessive although in Florida there aren't any other 1hdt's around to compare it to I've seen. We did timing belt, valves, fuel pump, rebuilt turbo and new injectors when we did the swap and engine only had 130km on it. I've also added an inter cooler. Any ideas? I've played w/ fuel pressure without significant luck...

 

[doug720]

Black smoke is usually over fueling. Have you messed with the pump settings?

On the swap, are you running an inter-cooler? If yes, possible restrictions or it's too small.