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540i6UK

540i Injector voltage ?

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Am planning to clean (and replace filters and O-rings) on my standard  injectors.

 

What voltage should be used to 'click' them and NOT damage the internals ?

 

Thanks.

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Ideally use an oscilloscope to measure the voltages whilst the car is running before you remove them

 

Most ECU related stuff seems to be 5V but that's just a guess

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Thanks. Can and will do that.

[I did wonder about starting at 1.5 volts as someone on the dreaded YouTube made that work ...]

 

Overhaul kit (filters, O-rings, seals) turned up today from MasterInjector.

Edited by 540i6UK
Adding

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Used 5V in the end and it works.

 

Re. getting at the injectors on the E39 V8 .... etc.

 

Usual advice about depressurising injection system applies first of course.

Found that removal of nearside 'electrics box' should be first - when injectors are unplugged it can be lifted - it then gives more cable leeway to remove the offside 'box'.

BTW  Thread on another site suggested just pulling 'box' to disconnect plugs/connectors on the injectors. It does NOT work - as the plugs stay put and just unclip from the electrics 'box'  ...   I had to gently flick off each of the stainless wire clips with a pointed scriber (engineers for the use of), then remove each plug.

To remove the fuel log you need to disconnect all 8 injectors to give enough room to gently pull the  log forward and out -  after quick-disconnect on petrol feed is undone.

[I removed each securing clip holding log to injectors - Note:  they are slid in from the outside ... NOT as per the illustration on RealOEM  - using needle nose pliers to avoid loss of flying clips!]

Remove dirt from around each injector before removal.

 

Other thread also suggests injector filters can be 'removed with a screw' - again did NOT work as the very thin brass  filter top just expands and tightens - SO with the injector lightly held in a fabric-wrapped vice, I used a very fine screwdriver tapped gently down to distort the thin brass inwards on one side - thus when loosened by destroying the 'circularity' - they came out easily.

Backflushed and reassembled with overhaul kit parts.

Oh yes ... oddly the RealOEM illustration I found does NOT show the plastic washer fitted at the very bottom of each injector .

New ones come in the overhaul kit.

 

Edited by 540i6UK
extra info

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8 hours ago, 540i6UK said:

 

Other thread also suggests injector filters can be 'removed with a screw' - again did NOT work as the very thin brass  filter top just expands and tightens - SO with the injector lightly held in a fabric-wrapped vice, I used a very fine screwdriver tapped gently down to distort the thin brass inwards on one side - thus when loosened by destroying the 'circularity' - they came out easily.

 

 

 

Sorry but disagree with that as when I've overhauled injectors in the past, I used the "screw method" and it worked a treat. 

 

I held the screw in a vice, point up, then slowly screwed the injector on to it and with a short pull, out came the filter basket nice and easy.

 

The method you used probably worked for you, but I would be hesitant to recommend the "chisel method" to others as it could very easily mess up those expensive injectors if it goes wrong. 

 

I'm not in any way saying the "screw method" is bullet proof, just that it personally worked for me and that any one attempting to overhaul their injectors should proceed with caution as one can easily damage the fragile and expensive injectors :) 

Edited by boiliebasher

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Last month I cleaned my injectors on my 540i.

 

The injectors were removed and cleaned using washing up liquid and old tooth brush. This was just to get the grime off.

 

Then I removed the rubber ringscetc and, using a screw I removed the filters inside. 

 

Once everything was removed the injectors were cleaned in an ultrasonic tank. Just water and some detergent.

 

I then connected the injectors to a device that allowed to the injectors to open and close rapidly whilst being released in the ultrasonic tank.

This ensures me that the injectors are cleaned inside too.

 

Once that was done, I did the spray test. Using carb cleaner or clutch cleaner.

The injector was on the device to open and close the injector as the spray was pushed through. I could see the spray pattern and it was good. If it wasn't,,,,,,, the injector was released until I was happy with the spray pattern.

 

Important note......

Please make sure you spray wd40 into the injector after cleaning. It prevents any sticking etc in the injector whilst storage.

 

Then, reassemble the injector with new seals etc and use.

 

This method of overhauling worked for me. The results were amazing. I would seriously suggest taking time to do this. Don't rush this procedure.

 

Remember.... injectors are delicate precise instruments..... using a chisel in my book is a big no.... 

 

 

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36 minutes ago, amebb said:

 

Remember.... injectors are delicate precise instruments..... using a chisel in my book is a big no.... 

 

 

 

Agreed. Exactly my sentiments as confirmed above ;)

Edited by boiliebasher

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