cleaning out fuel injector bores?

[Knucklehead]

finally got some time off work coming up to pull the injectors for long overdue service.

Was wondering, after the injectors come out easily without any issues , what would be the best way to clean out the bores?

Thinking with 200k on the injectors it could be messy in there and probably best to be clean the bore/seat before fitting injectors back in.

Would a round brass type brush cause damage to the bores?
Was also wondering how to stop any crud that comes off during cleaning falling into the engine.
Some way of plugging the hole that still allows a brush to be used would work I guess.

Any advice from anybody who has replaced their own injectors appreciated.

Dave.

 

[Chris]

12 gauge shotgun brush fits perfectly. I wouldn't worry too much about small bits of soft dirt falling in. They'll soon blow out of the exhaust. I used some brake cleaber and an air line to clean around the injectors before i pulled them out. They can be oily. Shift as much as you can. Use a bronze 12g brush to Clean the well where the injector sits. I wouldn't mess with the actual nozzle hole at all. You shouldn't need to. It's the seat that need the cleaning so that the new washer sit square.

 

[Knucklehead]

cheers chris.

I take it that the brass 12g brush is ok?
There are some nylon versions about.

 

[Chris]

Think about what the brush is for. It's for cleaning the bore of a gun? Polished, shiny, expensive and valuable. Nylon, brass or Phosphor bronze, if it's good enough to shove in a barrel, it's going to be fine in an engine. There are different styles though. That's the key. Cheap twist ones have a steel eye at the end which will fit down the nozzle seat. Not sure I'd want that. I have a Turk's head one that is flat at the end. It will get into the corners of the seat. It's more important than the material I think.

 

[Knucklehead]

Sounds good.
Thanks,
Dave

 

[Richards919]

Did you gents come across any issues with removing the injector seat? I’m battling to remove mine. Got one of them out with an M8 slide hammer tool but the rest I’m not winning with.

it seems that the M8 threads through the washer in and into the head. Mine are well stuck and think the might be original with 170k miles on...

Any advice please?

 

[Chris]

Holy thread resurrection Batman. Slide hammer usually does the trick I have to say. They're pretty soft washers. You might try an airline in there to clean it out really well and then try a bit of solvent perhaps. Not a lot, but maybe something like carb cleaner, acetone, petrol or something to try and dissolve the gum in there and keep trying with the slide hammer. Perhaps if a parallel thread doesn't work you might have to try something with a tapered thread that really bites in there.

 

[Richards919]

Plenty searching trying to find alternatives - hence the thread resurrection...

I have soaked with a WD40 alternative overnight and will try again this morning. Issue is that the copper washer has now opened up and I feel that the M8 thread is probably cutting into the head. Will try find something tapered.
Failing that I have seen some people simply using force and cutting the copper washers up. Think an injector seat reaming tool would save potential seat damage?

 

[Chris]

Tough one. Sounds like they're stuck well. I wouldn't have used WD though. I really was suggesting something more of a solvent to try to shift the gum that's holding them in.

 

[Richards919]

Yeah I soaked with carb cleaner also...

Having a tool made up now similar to the laser tools washer puller. Let’s hope that does the trick.

 

[Richards919]

So, for some feedback here - I ended up making up a tool similar to the Laser Tools piece. Basically fitted a 10mm easy-out onto a round bar, with a slide. The seats were still extremely difficult to remove, but managed to get them all out.

 

[Chris]

Well done. Exactly what I had in mind. They were well gummed in there.

 

[Richards919]

Very much so! Thanks for the input...