smokey startup.....

[ant_43]

I know it's a common problem with these old diesels, but my smokey startup persists and i'd really like to fix it finally! I've read through a lot of threads on this here, but thought it worth asking about my specific problem.

Engine spec: 1.9td aaz, K03 turbo, GTD/1.6TD Injection pump timed to 0.95mm, GTD injectors, newish glow plugs, newish battery, slightly upped the fuel (1/8 - 1/4 turn, which i think it needed for the 1.6 pump to suit the 1.9).

To try to eliminate the smokey startup i have replaced the glow plugs, battery, had the pump timed, and just recently had some rebuilt GTD injectors with new nozzles fitted. I was hoping that the GTD injectors would clear the smokey startup problem, but it actually smokes more now and i seem to have a bit of a miss on idle and low revs (which i've only noticed since installing the new GTD injectors)?

On cold starts i have a lot of white smelly smoke, and have to use the cold start knob or rev it, as it runs so rough and it will stall quite quickly. If i do use the cold start knob the smoke clears considerably and the engine idles smoother. I shouldn't need to use the cold start knob in the UK right?!

After it is warmed up and with the cold start knob pushed in, the engine seems to idle quite nicely, apart from with a little miss every now and then? The engine seems to perform well, and the new injectors did have an improvement with the performance, although i am only getting approx. 36mpg. The engine starts fine from warm.

This morning i started the engine up and looked it over and noticed a small amount of the same white smoke appearing from the back of the head - by the exhaust manifold. I could not see exactly where this was coming from. It seemed to disappear once the engine had warmed up. There is no sign of oil in water / sludgeyness in the expansion tank, and the oil looks fine which would suggest headgasket is ok?

I am running out of parts to change to fix this now, please help!

[veedubcanuck]

 All depends on the temperature there really. How cold is it out? As the age of the vehicle goes up then things do wear and they like to start with more advance..

[burn_your_money]

and have to use the cold start knob or rev it, as it runs so rough and it will stall quite quickly. If i do use the cold start knob the smoke clears considerably and the engine idles smoother. I shouldn't need to use the cold start knob in the UK right?!

Your car is telling you that you need to use the cold start knob.

Do you have an afterglow on the glowplugs? AAZs normally have one.

[8v-of-fury]

What about bumping the timing up 0.05mm? to 1.00mm or even 1.05mm if it likes it.

It helped my old smokey 1.6 tremendously lol. I upped the timing to 1.02 (n/a motor) from what i believe was set at or around 0.90-0.95.. Smoke went away completely.

[rabbitman]

I too think it needs more advanced timing, seeing how the cold start knob help it anyways.

Also IIRC GTD injectors have a higher pop pressure which will retard the timing even more, hence why it made more smoke.

[ant_43]

Thanks for the replies. That makes sense to me to perhaps bump the timing up a bit to suit the injectors. I spoke to the garage that fitted the injectors, (next door to my work!) and they have suggested that also. Unfortunately they don't have a dial gauge, for that i have to use the other garage that rebuilt and tested the injectors 

For now i've reduced the fueling a little, which has reduced the smoke slightly.

[8v-of-fury]

For now i've reduced the fueling a little, which has reduced the smoke slightly.

You could reduce the fueling completely, but if the pump is injecting fuel to early (retarded timing) it will always smoke. The fuel is being injected before it has time to burn properly, and then getting shot out the tail pipe .

I'll put money on advancing the timing

[ant_43]

For now i've reduced the fueling a little, which has reduced the smoke slightly.

You could reduce the fueling completely, but if the pump is injecting fuel to early (retarded timing) it will always smoke. The fuel is being injected before it has time to burn properly, and then getting shot out the tail pipe .

I'll put money on advancing the timing

I understand. I hope doing the timing is going to sort this out finally! It's booked in for friday so we shall see!....

[8v-of-fury]

Well if it is already timed to 0.95mm.. they may time it close to that for when they do it. Tell them to time it to 1.05, a lot of stock td's like this with normal nozzles. With your GTD nozzles and higher popping pressure they will probably like it being timed that advanced.

Ask them what they are going to time it too. anything over 1.00mm is probably ok. Higher then 1.05mm may be too high.

[rabbitman]

You could reduce the fueling completely, but if the pump is injecting fuel to early (retarded timing) it will always smoke. The fuel is being injected before it has time to burn properly, and then getting shot out the tail pipe .

I'll put money on advancing the timing

8V you lost me on that one haha , earlier injection is called advanced timing and the fuel can't be injected "before it has time to burn properly" . It can only get shot out the tailpipe unburnt when the timing is late (retarded)

Perhaps I read it wrong?

[8v-of-fury]

You could reduce the fueling completely, but if the pump is injecting fuel to LATE (retarded timing) it will always smoke. The fuel is being injected, doesn't time to burn properly and is getting shot out the tail pipe .

I'll put money on advancing the timing

One word wrong and your on my back I still had the right idea goin on eh lol

[rabbitman]

You could reduce the fueling completely, but if the pump is injecting fuel to LATE (retarded timing) it will always smoke. The fuel is being injected, doesn't time to burn properly and is getting shot out the tail pipe .

I'll put money on advancing the timing

One word wrong and your on my back I still had the right idea goin on eh lol

haha that's better

[ant_43]

Right, i've taken it to the garage and now have a big question...

I stayed at the garage while they did the work and asked lots of questions, plus that way i don't get overcharged hehe.
We advanced the timing, not using a gauge though, by ear. It now starts a lot easier, runs better when cold, and minimal white smoke on startup. Although there is still some white smoke, and a little miss / popping remains. I understand this could be valve stem seals? - Requiring taking the head off. 

Anyways, my big question. With the GTD pump fitted to my AAZ, the pump pulley is not in line with the rest, thus the cam belt has been running off the centre of the pulley and has been wearing away.  This is obviously a major concern and something that requires attention asap.

Now the garage could not understand why i would want to use a 1.6 gtd pump and 1.6 td injectors on a 1.9 engine. I used the pump originally because it had less electrical gubbins on it and i have heard they are more tuneable, but now i wonder whether it was the right thing to do. 

I still have the original AAZ pump. So now i have a decision to make for when i replace the cambelt.

1. Keep the gtd pump fitted, but use the pulley fitting from the aaz pump on the gtd pump. (The garage said this would be possible so as to bring the pulley back in line)

2. Put the original AAZ pump back on, and remove the unrequired electrical bits. It is a late AAZ pump, which has a vacuum mechanism for cold start advance. Also, it has a domed LDA, but no "smoke" screw. I assume i'd be able to use the GTD LDA on the AAZ pump top? If i use the AAZ pump would i be advised to go back to AAZ injectors?

The garage mentioned the GTD pump has an 8mm element, while the AAZ pump has a 9mm.

Clearly i need some advise from the knowledgeable people here! Which pump would YOU use - or do i use parts from both pumps to build a "super pump" 

(Sorry for the length of this post!)

[Rabbit on Roids]

the pumps both have the same pump heads. 9mm. the AAZ pump has a higher lift cam plate tho.

[ant_43]

the pumps both have the same pump heads. 9mm. the AAZ pump has a higher lift cam plate tho.

Ah. The mechanic checked the pump numbers in a book which told him that the elements (is this the same as the head) were different sizes, 8mm and 9mm?

Should i put the aaz cam plate on the gtd pump?