930 injectors

[Alan L]

I am still progressing thru my newly aquired 930. Which is keeping me fully occupied. So far after about 2 weeks ownership and 50 hrs work, I've done about 5 miles. A lot of that was figuring the burnt wiring under the dash and re plubing/wiring the fuel system to the way the factory intended. All works a treat now.
Tested my injectors today. The fuel rates are extremely consistent, but the patterns are lousy on most.
Can these bits be serviced?
Thx
Alan

[spuggy]

They can be cleaned and tested, but this isn't guaranteed to fix any issues, although it sometimes helps. I think Pelican member witchdoctor does it, and his service is well-regarded.

Flow matching and ensuring a good spray pattern are both Good Things.

Still available new, just not no-brainer cheap...

IIRC, there's a specific warning in the Bosch serviceparts fitment manual regarding the 931 (924 turbo) & 930 CIS injectors, saying that although they may look identical to many other (much cheaper) injectors with similar specifications, they have a special threaded portion to secure the fuel line and prevent it blowing off under boost. Yah, I can see how that would be bad...

The US and RoW injectors have different part #'s too, lore is that the RoW ones flow slightly more.

[Alan L]

Hmmm, I replaced my SC injectors a while back and that was not cheap. Having to do these ones will break the bank at the moment - already have a load of stuff coming from Pelican. The more I look, the more I see $'s. Feel like shutting my eyes.
Would like to try and salvage these ones first. Anyone any idea what they clean them with - prefer not to send them out of country at moment - trying to get this thing on the road.
Alan

[A930Rocket]

I think new they are about $50 a piece now. I would soak them in a container of Techron Injector Cleaner for several days, shaking it once or twice a day. When you pull them out, insert the red hose from a can of brake cleaner in the open end, hold it tight and spray. It will help clean it out and show you what pattern you have. I've done this for several and it's worked great.

[Alan L]

Originally Posted by A930Rocket

I think new they are about $50 a piece now. I would soak them in a container of Techron Injector Cleaner for several days, shaking it once or twice a day. When you pull them out, insert the red hose from a can of brake cleaner in the open end, hold it tight and spray. It will help clean it out and show you what pattern you have. I've done this for several and it's worked great.

That sounds good to me. I'll try it this w/end. Pelican have them listed at just over $100 ea. At $50, I'd probably grab them, but I also end up with shipping costs often as much or more as the item cost. (my current order with Pelican has $US450 freight costs). I'll try this method.
Thx
Alan

[AngM018]

I sent mine to witchdoctor. fast turn around and found out I had a leaking injector. 930 injectors aint cheap. they are in the 100 dollar range each

[RarlyL8]

I've got a couple of sets of injectors I am not using.
One set is new, never used, and has been flow/pattern tested by a local shop. They were ~$100 each new plus the flow testing. I'll give you a good deal on them if you can't find anything local. I can get you a shipping quote as well.
Shoot me an e-mail if interested.

[DonE]

www.injectors.com also matches injectors for best pattern and consistent volume. Reasonable too.

[timc]

Originally Posted by AngM018

I sent mine to witchdoctor. fast turn around and found out I had a leaking injector. 930 injectors aint cheap. they are in the 100 dollar range each

John - Was he able to correct the leaking injector by cleaning?

Tim

[AngM018]

Nope, it failed on the first test, so then they cleaned it. it failed again so they suggested a replacement.

[ayglass]

I recall using a cleaner/tester years ago in a shop I worked for. It was all set up in the clean room and consisted of a lever attached to a pump cylinder and a gauge. The injector pointed into a can to catch the spray. Simple and effective if you have one. It's probably an antique now with electronic injection, but I would like to get one...

Does anyone know where I could get one of those now?

[AngM018]

Originally Posted by ayglass

I recall using a cleaner/tester years ago in a shop I worked for. It was all set up in the clean room and consisted of a lever attached to a pump cylinder and a gauge. The injector pointed into a can to catch the spray. Simple and effective if you have one. It's probably an antique now with electronic injection, but I would like to get one...

Does anyone know where I could get one of those now?

There was one on ebay just last week. I dont think anyone bid on it though.

[Alan L]

I will post something in a day or so.
I have a cheap somewhat crude system going that seems to work fine.
Cost about $10 to make - assuming you have the other simple bits.
Am using it to flush the injectors at the moment - but it equally well tests them.
Regards
Alan

[JFairman]

I've seen guys put in lots of injector cleaner like techron, then rev the engine up and clamp off the fuel return line with needle nose vise grips and a thick rag around the jaws to raise pressure up as high as the pump will make it.

I havn't tried this but he said it seemed to help clean the injectors.

You will dilute the engine oil some with the extreme rich mixture while doing this so changing oil afterwards is a good idea.
Also if the return line is old and dry rotted it will probably be destroyed and leak from clamping it so a recent flexible return fuel line is also a good idea.

This was on a EFI car so I'm not sure if the increased return line pressure might do something bad to the CIS system.

This may be a bad idea so try it at your own risk if you want.

[Alan L]

Here is what I made up - cost about $10. That was for the Tee piece and hose nipple. I robbed the gauge off my home made CIS system tester (no point buying two gauges of the same pressure range). I used a cylinder of gas for the pressure system. Most gas bottles would do - Argon, oxygen, CO2, but I suspect a home workshop compressor would do equally well. I set the regulator at just above the test pressure. I filled the plastic line with injector cleaning fluid, hooked the hose on the nipple and opened the gas valve. You don't get long to read the gauge, but it works - as one of the pics show. You could increase the reservoir size by longer tube, or screwing an elbow fitting where the nipple is, then the nipple into the elbow. I use 5-10 ml of solution per shot. You can see the good/bad spray patterns and measure the pressure at same time. The spray patterns did not show up too well in pics to show good/bad - but they are fairly obvious.
The Tee piece was just a regular unit at hardware shop that just happened to have same thread as injector, and the gauge. I turned up a small disc (delrin?) to push fit inside the tee for the injector to crush seat on, since the tee internal is not same as injector seal.
Do not use teflon/plumbing tape to seal the threads - it wants to dissolve in the cleaning fuid - which means it would get into your injector = bad spray pattern. You are not supposed to get it on your hands either, but I was not too good at that bit. Some gloves maybe.
Regards
Alan

[Alan L]

The cleaning seems to be working. Initially I only had one injector with a decent pattern. I now have only one injector with a poor pattern. I will continue flushing it. I hooked them up to the CIS to test them. Initially I thought the whole exercise was a failure - all the patterns were lousy. But as the fuel washed the cleaning fluid out, one by one they came right.
Took about 25-50 ml of fuel/injector to wash the injector out to a good pattern.
The ideal system might be a recycling pump on this system - you could leave the injector plugged in for an hour or two. I have such a pump and may give it a shot.
Alan
Alan

[JFairman]

i would not use compressed oxygen with flammable liqueds... might go boom in a big way.
compressed nitrogen would be best but argon or plain old air should be fine.

[pdqcarrera]

Hey Alan, thanks for the excellent info, but more importantly now ... what varietal(s) do you have planted there in the background and is that a real RUF front bumper/valance?

[Alan L]

"Hey Alan, thanks for the excellent info, but more importantly now ... what varietal(s) do you have planted there in the background and is that a real RUF front bumper/valance".

Yes, I expect it is the genuine - I have the rear one off at moment - sorting a few issues, and it has a RUF insert on the inside of it.
The vines are Syrah - this winery began the Syrah journey for NZ.
About two rows further left is the original source row of the vines for the entire country.

I agree with JF, that oxygen as the gas source might be a bit risky - especially since the cleaning liquid is some hydrocarbon mix - I suspect toluene or similar.
I drew the line at acetylene - but was trying to think of what gas people may have available. But probably best not oxygen.
Finally got injector # 6 going this morning. Should run good on all six now.
You need to take care everyting is really clean. I flushed my 'machine' out with brake clean first. Ideally there would be a fine filter in the line ahead of the injector. That would be the Mk2 version with a slightly more sophisticated reservoir.
Shopping for a wideband O2 system now.
Slowly working my way thru the list you guys helpfully posted for me early on about care and feeding of 930's. One day I'll even get to drive it.
Alan