[Umanist]

I have finally learned I have injector blow by, proven by faint traces of exhaust gases around the injector area and confirmed by squirting dilute wash up liquid around each injector till it pools, where by blow-by soon bubbles rapidly then lets by all fluid. Just one injector showed no bubbles and the pool remains intact .

All this after much replacement of unnecessary parts.

OK , so I already bought 3 replacement injectors , four new nozzles and copper washers and O rings!

Zero result! Still getting exhaust gases from around the injector rim! At this point I did not know about blow-by!

I then was told they likely need the seats reaming.

Next I buy a reaming tool and reseat , under careful and sustained turning of the tool until all injector seats appear shiny and gleaming from above and also give no feedback of "judder" as the reaming blades glide over the injector seat under minimal pressure.

I repeat the reaming of the injector rim itself, prior to fitting new copper washers to all 4.

On starting the engine and trying out a tip I got only yesterday, I squirt wash liquid around each injector and all but one still bubble s rapidly , indicating blow by still is occurring . I am baffled as to how to seal these injectors?

I imagine only the copper washer seals cause the fault where injectors can experience blow-by?

Or can blow by come via some other seal within the injector area?

For example - I could not locate any of the rubber rims that lie within the cylinder head-injectors area and have no idea if these need replacing or indeed where to get any?

Also I would like to know the exact torque method and specification on the injector bolts?

I am sure I have torqued these enough since I marked each one before removing it so as to give me an idea of the tightened position of each bolt. It still makes no difference.

This  blow by seems impossible to stop and I am now baffled by this problem, despite all the correct tools and various parts?

Any advice would be most welcome.

[tw2005]

I have finally learned I have injector blow by, proven by faint traces of exhaust gases around the injector area and confirmed by squirting dilute wash up liquid around each injector till it pools, where by blow-by soon bubbles rapidly then lets by all fluid. Just one injector showed no bubbles and the pool remains intact .

All this after much replacement of unnecessary parts.

OK , so I already bought 3 replacement injectors , four new nozzles and copper washers and O rings!

Zero result! Still getting exhaust gases from around the injector rim! At this point I did not know about blow-by!

I then was told they likely need the seats reaming.

Next I buy a reaming tool and reseat , under careful and sustained turning of the tool until all injector seats appear shiny and gleaming from above and also give no feedback of "judder" as the reaming blades glide over the injector seat under minimal pressure.

I repeat the reaming of the injector rim itself, prior to fitting new copper washers to all 4.

On starting the engine and trying out a tip I got only yesterday, I squirt wash liquid around each injector and all but one still bubble s rapidly , indicating blow by still is occurring . I am baffled as to how to seal these injectors?

I imagine only the copper washer seals cause the fault where injectors can experience blow-by?

Or can blow by come via some other seal within the injector area?

For example - I could not locate any of the rubber rims that lie within the cylinder head-injectors area and have no idea if these need replacing or indeed where to get any?

Also I would like to know the exact torque method and specification on the injector bolts?

I am sure I have torqued these enough since I marked each one before removing it so as to give me an idea of the tightened position of each bolt. It still makes no difference.

This  blow by seems to stop and I am now baffled by this problem, despite all the correct tools and various parts?

Any advice would be most welcome.

I've never touched a diesel injector in my life so keep that in mind as I give an opinion.

I've put an image up from the web so we get some idea of the setup. I see 2 O-rings and a copper washer.

Having read what you have written this strikes me.

How can you say

I am sure I have torqued these enough since I marked each one before removing it so as to give me an idea of the tightened position of each bolt. It still makes no difference.

Keeping in mind you've also reamed the seats the only way to be sure would be to torque to the recommended value.
I'm also wondering about that square seal which appears to be below that copper washer



Injector clamp installation bolt: 28.4 ~ 30.4 N·m (2.9 ~ 3.1 kgf·m, 21.0 ~ 22.4 lbf·ft)
High pressure fuel pipe installation nut: 24.5 ~ 28.4 N·m (2.5 ~ 2.9 kgf·m, 18.1 ~ 20.1 lbf·ft)


 33805-2A000   O RING-INJECTOR   




 33818-27000   GASKET-INJECTOR   



 33820-2A010   SQUARE RING(B)   

[Umanist]

Thank you for that post! 

I can't see the diagrams very well since they are small scale and when I copy to enlarge the focus is lost. I may need to find a direct link to this manual - wherever it is?

I'm pleased you got me a torque - which google never displayed for me!

The seals I was referring to are in the hole that the injector goes into. Around the top in the engine block .

The nut on the end of the injector is octagonal and is impossible to undo unless you have a special socket ( which I could not locate anyplace online) and so bought a 1945 post war square hand clamp to assist me in undoing these and re-tightening, since they are extremely tight. I needed a vice to hold the hand clamp whilst I applied a large spanner to the two flat sides nearer the top of the injector.

I also bought some nozzles from a company in China ( since these are not supplied by any injector supplier in the UK from my online searches????) which I would not recommend to anyone since under which magnification their holes are at least twice the diameter of the Bosch nozzles (0.1mm) and also irregularly positioned. I discarded these as useless.

I am trying one last idea that I don't think will solve the issue but here it is.

27612 Febi Bilstein ceramic grease is what is recommended to apply to copper washers on Mercedes engines so I am going to try it. This is the only product I have seen anywhere that is recommended as an addition to the regular advice on new copper washers .

Another idea on you tube showed someone putting a film of exhaust repair paste on each side of the washer,  to infill any  discrepancies between the mating surfaces . This person claimed it resolved blow-by. This idea is not recommended by any professional advice on resolving blow-by but I can see the attraction when all else is failing.

You would need to be very cautious about getting excess paste squeezing into the cylinder on tightening and also it might be less easy to remove injectors next time. I may try it but to be honest I don't feel confident after everything I already did failed completely.

At present I am thinking this i30 is going to have to be sold off and I will be well shut of it !

I will endeavour to take and post some pics to show a few things when I get back on this job in daylight.

Plus the sides of the rabbit hole I am down with this i30!

[tw2005]

click on image, go to top and click on expand to actual size, you should have no issue reading it.

[tw2005]

Beyond me, sounds like you're neck deep.



?????? ????????? ????????? ??????1.6 CRDI ? ?????????? KIA Ceed SW Turbo Sa??? 2008 ???? ?? DRIVE2

[Umanist]

Those photographs are very interesting!

If those seals were compromised ( and who would imagine 3 would leak simultaneously on only 100,000 miles? ) then I still don't fully see how it would meet the condition I am having?

However one feature seems to suggest a link to this : I find that if I remove the oil filler cap the exhaust gases stop coming out around the injectors . This puzzles me because :

(1) I thought the gases were straight from the cylinder and up the sides of the injector so why would removing the oil cap reduce exhaust gases that I thought were from the cylinder ??

(2) If the gases do come from the oil filler cap why would this be the case anyhow - and they then escape through those seals - rather than around the copper washer to the cylinder?

(3) Why is the iddling so erratic? (a) As is known to be the case if the copper seals are failing.
(b) But is this also the case if for some reason and somehow exhaust gases are getting in to the top of the engine and flowing past those seals ?? - An idea only suspected because they seem to stop whenever the oil filler cap is removed.

Hence I am not sure what the exact problem is or if I am even addressing the source of the exhaust gases from around those injectors ?

[tw2005]

I have not read all of your last. I stopped when you mentioned when oil cap removed bubbles stop which is what was in my mind, is this exhaust past injector in head or simply a bit of crankcase gas past the O'ring past the rocker cover.

If that's the case I would not think that would be a major issue or cause performance issues.

But with all of what has gone on, there could be other issues now introduced. Sounds like a job for a diesel injection specialist.

[Umanist]

As a resume of the 4 nozzles I got and the suppliers claim I do not know what I am talking about, which I am always willing to concede and take note of if in fact that is the case? I am no nozzle expert. However the area of a circle is pretty obvious and I imagine has consequences under high pressure fuel injection? I wonder if anyone with "nozzle expertise" might have a clue if there is nothing to be concerned about in the following?

Note the picture showing 5 nozzles of seeming similarity ( 4 new from China and one from an existing Bosch 33800-2A900 injectors.

However, then look at the magnification - to display exactly how different the jets diameter is - and how weird where 3 holes form a triangle on one new nozzle - all of which have a different pattern of holes.
 






image of a safe

[nzenigma]

I have not read all of your last. I stopped when you mentioned when oil cap removed bubbles stop ...But with all of what has gone on, there could be other issues now introduced. Sounds like a job for a diesel injection specialist.

Just waded through the posts and stopped at the same point, same conclusion.

Take crankcase pressure Vs combustion chamber pressure  . crankcase can have no influence.
If the two were linked you wouldn't have an oil cap to remove.

[noels_hobby]

This was mentioned to me some time back about injectors getting blow by and to change the clamps at 50k as they loose tension, I mentioned it to the dealer at 50k and they thought it not necessary. After reading your post I am wondering now if there is and merit in the original story
noel