Gunk on top of engine.

[VolvoButler]

Hi all,

59 plate. 1.6D eco

Any ideas what might cause a heavy, greasy, almost thick oil like sunstance build up located on top of the engine between the two middle injectors? I'll get a picture in the morning uploaded to show you all.

Today I replaced my alternator as had some weird electrical issues and found it was faulty. Upon removing the engine cover I noticed this thick build up on the top. I also noticed the air filter intake hose had its clip missing and the pipe is loose (new one ordered) so I wondered if because this pipe was loose it would cause a build up of gunk from the engine?

Any ideas welcome and thanks in advance.

Andy.

[Lukasguy]

Is your engine the older 1.6 or the newer 1.6 D2? (older if you have a 5 speed transmission, newer if you have 6). What you describe sounds like one of the 2 middle injectors (or both) is leaking. This appears to be relatively common with these older 1.6 engines. A possible fix for this is to remove the injector, clean everything and replace the copper plate that seals the engine and the injector.

[TeamG]

It does sound like a leaky injector leaving a mist on the engine that has been attracting dirt and soot from the air over a period of time. Have you dipped a finger in it and smelled it? Does it smell like fuel?

[VolvoButler]

Thank you to you both for your replies.

It is the older 5 speed version.

Upon further inspection of what I thought was gunk and looked wet, and like grease or oil, when I dipped my finger in to smell it to see if it smelt like petrol, it is actually rock hard! It's a solid black coating that must have dried due to the engine warmth when running and built up over goodness knows how long.

As you can see from the pictures it is around the third injector in the center area and looks wet but is actually rock hard. Almost like carbon or something. There is an overall engine view and a couple of close ups.

https://drive.google.com/file/d/1cDt...ew?usp=sharing

https://drive.google.com/file/d/1Ll-...ew?usp=sharing

https://drive.google.com/file/d/1j6o...ew?usp=sharing

I've had the car a year, and it's always been a bit smelly. After a drive and I get out it has a burning, oily, car smell wafting from it so I imagine this build up might be the cause of that.

What should I do? Attempt to clean it all up and keep an eye on it? Or explore it further to find the cause? I'm pretty confident with car repairs, although I'm not a mechanic by any means.

If I remove the injector(s) is it obvious whether the copper seals are damaged?

Many thanks,

[Lukasguy]

That looks like cylinder 3 is leaking to me.

I don't have any experience with the older 1.6 engines as I have the newer 1.6 D2 where I replaced the injectors from. Though I did read a lot about this while searching for information about my engine.

I think it would be best to remove the injector, clean everything as well is the injector (be careful not to damage the small tip), the injector hole & the surface where it sits on. Replace copper seal, plastic or rubber mounting thingy & mounting screws. Be careful when torqueing the screws as I read a lot of them snapping when too much force is applied. You can go to your local Volvo dealer for these parts.

Helpful videos can also be found about this on Ford cars (DV6 engine) or Peugeot (1.6 HDI). It's not always clear if the guide is the old or the newer engine, but the two engines use different injectors, so this can be a good indicator.

[pinballdave]

That looks like a leaking injector seal, which is a common problem on these engines.

The copper washer seal is likely to be eroded and if it's been going on for a while, it might have also damaged the area of the cylinder head where it seats.

This causes combustion gasses to leak past and you get thick hard carbon deposits around the injector. The deposits are quite stubborn to remove, but carb cleaner or cellulose thinners and plenty of elbow grease usually does the trick.

It's worth spraying carb cleaner around the area to soften it up and give it some time to soak in before trying to remove the injector. The carbon gunk will be all down the sides of the injectors causing it to stick in the head. Use a spanner to gently twist the injector back and forth before attempting to pull it up, and keep spraying the carb cleaner!

The seals are cheap and easy to get hold of, so if you're going to take the injector out, then it's not worth attempting to reuse the old ones.

It's also probably worth getting a cheap set of injector seat cutters from eBay/Amazon for around £20, as it's important to make sure the seat in the cylinder head is perfectly flat.

As Lukasguy said, there's plenty of videos on the net showing how to replace them on the Ford and Peugeot versions of this engine, this one was the one I watched before attempting it and is quite comprehensive.

[NottsDave]

One injector on mine has these black hard deposits around it and a slight 'exhausty' smell when the car is stationary with the engine running, so this video link is very useful Pinballdave.