Hi, I want to do some cleaning of my injectors in '89 KR engine. Which oring should I change: nr 13 - oring 034133557A (9.8x1.4) nr 16 - oring 034133557E (6x5.2) nr 16A - normal ring 034133557 (16.5x19.5x1.5) One more thing, I read Haynes and they say: As I saw people normally dismantle injectors and clean them. Why Haynes say the shouldn't be changed? I want to clean them like in here: http://alabbasi.com/injectors.html I want be using ultrasounds. If it want work I will maybe buy new, after discounts I can get one for around 25-30 pounds (in Poland).
haynes means you cant open the injector itself and clean the internals, this is impossible. you can run them thru an ultrasonic cleaner once out the car or whatever if you like though 034133557 is the injector insert seal, only needed if you remove the inserts from the inlet. the other 2 are the injector seals
I managed to take out first two injectors, two others are kind of blocked. I used Brake Cleaner, WD40, and some compressed air. I left them in Brake Cleaner for 5 hours. I thought that they were blocked, beacuse at the end I had problems to spray Brake Cleaner through them. But when I put them back inside the engine they were working fine, noticed some slight improvment on idle.
Kjet injectors need lots of pressure to open them. Your brake cleaner wouldn't get through unless it's got about 5 bar behind it. I snapped an injector trying to take it out of an 8v engine the other night... they can get pretty stuck after 20 years in the same place.
For me the key-question hadn't been asked yet: Is there any sense in "cleaning" k-jet-injectors by other means as for example the commercial injection-cleaning-liquids that get added to the fuel? (Take for example Wynn's injection cleaner or similar products from liquimolly.) I obtained several times for me surprisingly good results.) The background of my question is, that Bosch indicates the operational lifespan of these injectors with 100.000 km. In my experience almost nobody ever spends the money (180-250 ) just to change some lousy injectors, so that there driving around KRs with injectors that exceed 2 to 4 times there lifespan. This together with a neglected regular setup of idle and CO might be one of the reasons for the myth, that a Digifant PB pulls better and goes faster than a 16V. (Inded there are no concerns regarding the lifespan of digifant-injectors.) Cheers
So off the back of this post and websifus' helpful comment, is it worth me actually taking my injectors out to clean them, (note I have an airline etc and an ultrasonic cleaner so can put pressure through them if needed) or is it going to cause more probs with cracked plastic guides etc etc? Sorry to hijack
you could always do a test on them first, take them out, bridge the relay and lift the flap. watch the spray patterns and measure the volume sprayed by all 4 to mkae sure its roughly the same
Something I've been meaning to experiement with, but there's always a load of other jobs ahead of it in the queue - The best way to do this 'should' be to rig up a fuel pump, spare metering head and lines, and recirculate cleaning fluid into a bath, that's then filtered and feeds back into the pump I have all of the above bits, but haven't tried it yet. I'm not 100% sure what to use as cleaning fluid - people speak highly of FORTE additive products. Any thoughts, folks? Even vinegar might do the job, but I'm not sure if it would have the right properties to lubricate the pump and prevent it from seizing. I've tried soaking injectors in vinegar before, without the pressure feed to open them up. It made them look nice and clean but didn't make much/any difference to the way they worked. I also swapped a few emails with one of the guys on ebay that offers an ultrasonic injector cleaning service... he reckoned he could clean Kjet injectors and improve performance, using a pressurised rig, but that it wouldn't fix injectors that were already leaking. Food for thought... Maybe there's another, easier way, with a compressor and a degreasing gun modified to fit on the end of a Kjet fuel pipe/injector setup. That would remove the need for pump/metering head, etc.
you may want to read the last post in this thread http://www.clubgti.com/forum/showthread.php?t=208200&highlight=Cleaning+Injectors as i said to mike then cleaning only makes the spry patern worse and as said ^^cleaing wouldn't fix injectors that were already leaking. the best way to test injectors is on the car ever pull them out one at a time to look at the spray patern you will need to plug the hole for the engine to run while you do this i use a spare Injector to do this rev the engine gently to see the spray you can all so do a flow test with them all out in jars the same size to see if you are getting the same from each one with the flap on the metering head held full open and the fuel pump relay bridged
Yes, it's really hard to put any pressure there. I also agree, as I wrote if cleaning won't work I'm going to buy new ones. After cleaning two of them, the idle improved (probably only one of them was not fine). But after cleaning the third one the spray pattern got worse and the idle got worse As I understand from your post in other topic, the part with number 3 gets broken (a) - injector open b) - injector closed ) ? Is there a way to verify if it's broken? If it's broken than the spary pattern is worse or the injector is leaking or both ? One more question, if changing the injectors I should change all of them to keep their output/flow as close as possible?
What happens is the sealing faces get pitted over time and leak giving a poor spray pattern Or the spring go's weak or brake
Thanks for the info. I wanted to try last thing, adding injection-cleaning-liquids to the fuel. It won't cost me much, just making last try. Can I go on trackday with this injector cleaner in fuel? Will the gasoline be enough quality after adding 0.5l on 55l of tank?
