blue smoke on start-up, only after overnight. Appears fuel not oil

[Robho]

I have a 2007 1.6 HDi. It has done 86,000 miles. 

In normal use there is no exhaust smoke.

After parked overnight, there is blue smoke on start up for, say, 2 secs and not scientific but to give an idea the amount of smoke would envelop half a van (very approximately)

Once used, if then parked and used a few hours later. No smoke. Seems only to be when left for a long period, like overnight.

Vehicle runs fine. 

Fuel consumption is normal 42-45mpg.

Doesn't use any engine oil. 

Been like this for a while, and not worsened.

Anyone had anything similar / suggestions for what I can check? 

Many thanks

[saskak]

Same with me and you can have a look at my posts/threads about this. Exactly the same, overnight and disappears within 5sec. Apart from the usual crankcase oily fumes, I do not think it comes from the turbo or anything else, I already replaced it and it is the same. I also do not think it is valve stem seals, that would also produce blue-ish smoke on standing at trafic lights and on the startup will have a puff of blue-ish smoke.
My working hypothesis is that the crankcase oily fumes when stopped (overnight) condense in the intercooler and then on startup under the pressure get blown in the intake. I have an idea how to test this, but will report when I do it.

My oil catch can tests seem to confirm the crankcase fumes pooling in the intercooler, but why it does not happen to other people is a bit weird.

[Robho]

Hmm. That sounds interesting. Someone suggested that it might be a leaking injector. I really dont have much knowledge of diesels.

[cancunia]

Hmm. That sounds interesting. Someone suggested that it might be a leaking injector. I really dont have much knowledge of diesels.

You can (and should) easily check the injector clamps on the 1.6 engine, you need a 7mm allen key. There are instructions on here but ask if in doubt. I think the idea about some condensate being burned off makes a lot of sense, I have a 2.0 HDi which does much the same. It may also be an initial amount of unburnt fuel, but I think we discounted that due to the smoke colour?

[Robho]

Cheers, I've just tried seactr (unsuccessfully) ...could you point me to the instructions pls? thx.

[Robho]

Cheers, I've just tried a search (unsuccessfully) ...could you point me to the instructions pls? thx.

[Sol]

On the early design of 1.6 HDi there was an issue with injector clamp bolts coming loose. Later models don't suffer this issue as the design was changed.

The early ones need to be tightened to around 10nm with a torx bit and a 1/4 inch ratchet with extensions.

(Factory spec is 4nm plus 65° final turn, but old style ones can break easily in the head, so best to be cautious.)

Also need to watch you don't snap off the leak-back stubs on the Injectors.

[Robho]

Cheers. Would my 2006 be classed as late or early in this context?

[cancunia]

Cheers. Would my 2006 be classed as late or early in this context?

2006 is early, later is around 2009 onwards. The earlier engines are 16v, and this is moulded into the engine cover.
I had a quick search for some instructions, but none jumped out.

I'm fairly sure that JJ9 & others have some views on how best to check & tighten, maybe post a new thread on the subject of how best to tighten them?

I sold my 1.6 a couple of years ago, so from memory..

Remove the engine cover
Undo the injector wiring guide, it's black plastic held in place with a couple of 8mm a/f head bolts.
Get a 7mm hex allen key & check that the injector clamps are not loose by applying a light loosening & tightening motion. I did this by feel and tightened the loose ones so they were no tighter than the tight ones (hope that makes sense).
There are 2 bolts per injector, they look like sleeve nuts and the 7mm allen key will only fit them.

[Robho]

Cheers. Would my 2006 be classed as late or early in this context?

2006 is early, later is around 2009 onwards. The earlier engines are 16v, and this is moulded into the engine cover.
I had a quick search for some instructions, but none jumped out.

I'm fairly sure that JJ9 & others have some views on how best to check & tighten, maybe post a new thread on the subject of how best to tighten them?

I sold my 1.6 a couple of years ago, so from memory..

Remove the engine cover
Undo the injector wiring guide, it's black plastic held in place with a couple of 8mm a/f head bolts.
Get a 7mm hex allen key & check that the injector clamps are not loose by applying a light loosening & tightening motion. I did this by feel and tightened the loose ones so they were no tighter than the tight ones (hope that makes sense).
There are 2 bolts per injector, they look like sleeve nuts and the 7mm allen key will only fit them.

That's great and will do, thanks again.