Injector Cleaning Gone Wrong

GTE

Howdy all,

Unemployment has taken its toll! I decided to start a project which I've been wanting to do for a while which is injector cleaning. I decided to do one at a time in case I messed something up and to aid starting the engine without having to prime the fuel system. Sadly, I messed it up

I used an ultrasonic cleaner with brake cleaner to clean it up after a google of guides and took the injector out following this guide.https://www.google.ie/url?sa=t&source=web&rct=j&ei=ZuhrU87WPMzY7AbHh4C4Cw&url=http://pics.tdiclub.com/pdf/injector_install_howto.pdf&cd=1&ved=0CCgQFjAA&usg=AFQjCNHcF0cx04AF78OxnIOjCblLe1E_pw&sig2=0D_iFS4DPqexW_7ZJRNqBg

I put it back in the engine and all was well for about a minute but a rough idle with EU emission quota busting amount of white smoke on revving developed.

Tis clear I messed it up but I was concerned that the injector was not sealed when I reinstalled as i didnt think that I pushed it in far enough so I'm wondering would a compression leak cause the symptoms? Could it be blocked nozzles?

Also, if you have a set of AGR injectors, I'd be quite obliged :-P

Thanks!!

rex-x

Did you change the fire seal when you re inserted it? White smoke is totally unburnt diesel so you would have to have a serious compression leak to cause that

Interslice

Did you leave it run a bit. Could have been just the air in the fuel lines.

GTE

Interslice wrote: »

Did you leave it run a bit. Could have been just the air in the fuel lines.

It's been on for a min and a half to 2 mins I suppose, I didn't want to run it too long. How long would it take for the fuel line to purge?

I didn't replace the fire seal. I put it in as far as I could and then put the retaining clamp in quite tight so I'm thinking its not gone far enough.

Interslice

bbk wrote: »

It's been on for a min and a half to 2 mins I suppose, I didn't want to run it too long. How long would it take for the fuel line to purge?

I didn't replace the fire seal either.

I put it in as far as I could and then put the retaining clamp in quite tight so I'm thinking its not gone far enough.

If it smoked the whole time and not just firing up I'd say it's letting air in. Your should change the seals whenever you take out or change and injector. Try them first and make sure it's all good and tight before there's any panic.

GTE

Thanks, shall have a proper check tomorrow. Fading light was my enemy tonight. Twas good fun until switching the engine on :-P

GTE

I have not had the chance to get to the motor factors to get that fire seal, but I took the injector out again and found an incredible amount of gunk around the nozzle. It was also extremely easy to slip out of the engine, so it looks like there was air getting in.

I took it apart, cleaned it up again with the ultrasonic cleaner and gave the injector slot in the engine a double going over with a hoover gentle brushing. When I put the injector back in, it was again extremely easy to slot in and out and there was a slight amount of wiggle room. I made sure the injector union thing was clean and quite tight.

On start up, the engine is in much better fettle. No obvious imbalance and there is only a small bit of smoke from the exhaust, only noticeable when you go to the back and have a good look at the pipes. There is still smoke however and when I let the engine go down to idle from 2000+ rpm there is a small plume of smoke as it hits idle. EDIT: After a test drive, the smoke cleared up so I guess that was unburnt fuel in the system getting sorted out.

Thanks all!

Chimaera

You still need to change the seal. They're copper crush washers and are single use only: the deformation on torqueing down the the injector is what creates the seal. Get a set of 4 of those before you go any further.

GTE

Chimaera wrote: »

You still need to change the seal. They're copper crush washers and are single use only: the deformation on torqueing down the the injector is what creates the seal. Get a set of 4 of those before you go any further.

Aye, they are on order. Now that I know the process of taking the injector out I will do them properly once I get the bits

Fun job after the initial world is ending part of it!

dr.fuzzenstein

I am absolutely fascinated by this thread. Would the procedure be similar for an '06 1.8 TDCI Ford engine?
No immediate plans, but one never knows if this might come in handy.

Chimaera

dr.fuzzenstein wrote: »

I am absolutely fascinated by this thread. Would the procedure be similar for an '06 1.8 TDCI Ford engine?
No immediate plans, but one never knows if this might come in handy.

It's rather more difficult I'm afraid. On the VE system, the injection pressure is about 200 bar and it bleeds off when the engine shuts off so it's safe for a DIY mechanic to go and play with the injectors without using special tools.

On common rail engines, the injection pressures are north of 1600 bar and don't necessarily bleed off after shutdown, so you need a special tool to depressurise the injector lines before you can remove the injectors. The injectors themselves are a little more finicky too but I'm not sure if this would get in the way of ultrasonic cleaning.

Ideally, the nozzles should be removed from the injectors and cleaned separately, and they should be lubricated with diesel before reassembly. Nozzles should be kept with the injector body they were removed from.

It's also worth bearing in mind that nozzles wear out over time. Anything over 240 000 km should probably be considered past its best and replaced. For the AGR engine, you're looking at about €300-400 to have new nozzles fitted and calibrated IIRC.

dr.fuzzenstein

280k km on mine, will have to look into it at some stage.
But so far going OK.

GTE

321869 KM on mine, but I swear that a cold start issue I had before I cleaned that single injector is gone now so I must have cleaned the lucky injector

No chance of me being able to afford new ones, but it would be something I would like to have somewhere on the project list. A wage will help this

I am happy with how the engine is running so I will do them all and change the pesky seals. I say pesky as the DIYs I have read say they are very difficult to get off.

GTE

The new seals arrived so I switched over the seal on injector 1.

The injector was quite easy to take out again.

I cleaned the socket very carefully and put the new seal in, then the injector. I couldn't turn the injector upside down without it slipping off, which makes sense if the fit doesn't have to be very snug.

There is noticeable diesel leak coming from the base of the injector and I can see some bubbles. There is also a slight metallic knock coming from the engine.

The retaining nut at the base of the injector is up to the specified torque, a bit over it actually.

The fuel return lines seem dry and the fuel line is quite tight. No signs that it is dripping down from the top of the injector, but the bubbles would be from the base anyway.

Does it take some time with heat for the new seal to seal properly or would there be something messing up the crush washer?
How about the thread between the retaining nut and injector body? I took these apart to get to the nozzle.

I have three spare washers, so I can try again but I want to wait for the engine to cool down.

My bet is the washer is being messed up by something but there is no smoke whatsoever, even during the rough idle while the injector was getting fed diesel on the first start, so no compression leak - from a DIY hobbyist point of view.

Chimaera

What do you mean by the 'base' of the injector? I'm guessing you're referring to the point where the high-pressure fuel line is attached. If that's leaking, it's not tight enough. Also, be REALLY, REALLY careful working around a leak there when the engine's running. High pressure fuel can penetrate the skin and cause serious injuries.

That copper washer sits between the (fully assembled) injector and the head to seal against compression. Replacing that washer should not involve any disassembly of the injector itself. Did you make sure to remove the old one? If you have torqued down the clamp correctly, the force from that will deform the washer to create the seal for you.

If it's a fuel line problem, it's nothing to do with the washer.

GTE

Thanks for the reply, my terminology is likely to be wrong. By base I mean where the injector meets the actual engine (visually). I would refer to where the fuel line is connected as the top - probably wrong in those, especially with base.

I took another look and made sure the retaining nut to injector body was tight, which it was. Then I inspected the crush washer and noticed that it was deformed unevenly.

I had an LED on a length of wire handy so I placed that down the injector socket and then I went into the engine with an artists paint brush found a wee bit if carbon/dirt which was not easy to see in standard light.

Gave it a going over, a hoover and refit the injector with a new washer and all is well for the moment at least.

Previous to my earlier post today, a short drive around the block was enough to show the diesel leak. This time, everything is dry.

Moral of the story so far is not to underestimate how a speck of dirt and cause headaches.