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General Information => Troubleshooting => Topic started by: neimis on August 11, 2013, 06:02:52 pm
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Injector is leaking between hard fuel line and injector. I can see it streaming out below the nut, so am quite sure it is not the return line.
First I tried reseating the hard line about 20 times, every which way, loosening the lines and clamps, reseating, aligning the line on the injector, tightening, loosening, etc. Nothing. Same leak every time.
OK, so I thought it was time to replace the injector line with a brand new one, did that. Same leak as before. Now I'm getting frustrated.
Is it possible/probable that the seating surface of the injector itself is damaged? I had no leaks for many years, nothing was touched.
Can the seating surface of the injector be touched up or smoothed with, say emery paper? I don't know how to avoid getting the injector contaminated with dirt and abrasive.
Any help or suggestions much appreciated, Thanks, Neil '92 Passat TD
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You are entirely sure it is seated and torqued properly?
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You are entirely sure it is seated and torqued properly?
I've replaced and installed lines and injectors a few times over the last 20 years. This time I've given it at least 20 attempts, and I'm pretty sure it's seated and tightened properly. I don't have any trouble with any of the other injector lines (replaced those with new lines cause I bought a complete new set).
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I've replaced and installed lines and injectors a few times over the last 20 years.
I wouldn't know. ;)
Interesting issue. Never seen one leak so incessantly.
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Threads Ok? Cross stripping on the nut or the top of the injector?
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Yes you can reseat the injector. You can use carbide rasp/burr to do it but odds are you are going to need to take the injector apart in order to get all the metal shavings out.
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Steel ball and emery paper plus oil and option?
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Threads Ok? Cross stripping on the nut or the top of the injector?
Threads are all good, they hand tighten without any resistance.
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Interesting issue. Never seen one leak so incessantly.
Puzzling that it suddenly happened out of the blue, after 4 or 5 years of no trouble... It's really gushing a stream.
(By the way, I did replace the return lines just to rule that out, but it's pretty obvious it's coming from under the nut)
I guess I'll try looking at the injector seat tomorrow with a magnifying glass to see if I can see any nicks or scratches, etc.
Burn, I'm not too keen on disassembling the injector myself. Do you think ORCoaster's suggestion might work? How would I keep the injector clean?
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Put the Injector on top of the ball so all the metal goes to the oil and paper. Rinse with WD 40 by dipping injector into a small container of it. Air dry with low pressure. We are talking filings here not shavings from a grinder or saw operation.
Inspect the top of the lines and the inside of the nuts. Might find a hairline fracture on the inside that gets larger as you tighten it down.
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It's a gamble. I'd make sure you have a spare that you can swap in incase everything goes wrong. I think you would want to cut the injector straight rather than rounded though.
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I have a hard time imagining a failure or void there. Those bodies seem to be tool grade steel or perhaps hardened.
I'd put the injector on a pop tester and see if it really is leaking there or a maybe flaw where the return barbs meet the body.
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I have a hard time imagining a failure or void there. Those bodies seem to be tool grade steel or perhaps hardened.
I'd put the injector on a pop tester and see if it really is leaking there or a maybe flaw where the return barbs meet the body.
Well, there is a stream coming out between the nut and injector. It's so big it is very easy to see.
It's a gamble. I'd make sure you have a spare that you can swap in incase everything goes wrong.
That sounds like good advice. Car is undriveable right now anyway, though.
I guess I should start looking for a spare injector. It's a two stage. Giles installed and balanced the new nozzles for me years ago.
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I wonder if its a leaky return line
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I wonder if its a leaky return line
Just to be sure, I've replaced the return lines with new.
It is very easy to see the big stream of fuel coming out between nut and injector, there is no mistaking it.
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What you "could" do it run a slight bit of teflon tape on the threads. You not "Suppose to" but if you are careful and tape the lower threads you should be all set.
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Wow, having worked in a fittings warehouse in the past we would occassionally see a batch of rejects come out with a dab or burr of metal on the inside of the nut. Could the new lines have a blob of plating that is keeping the face of the injector from flushing up to the new fuel line? Or the top of the line and bottom of the nut.
Streams of fuel really indicate a major disconnect with the nut, line and injector. Threads not worn, new nuts and lines? Time to look at quality of product I'd say.
Only saw it rarely, but it did happen. Sorry no pics, this was 35 years ago now.
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Yay! Success!
First of all thank you to everyone who replied. Special thanks to ORCoaster - your idea did the trick. In case anyone else runs into the same problem, here is the fix:
I removed the injector, inspected the sealing surface with a magnifying glass. Didn't see any obvious nicks or gouges, but there were some questionable spots. I took a ball bearing of the appropriate size, some 2000 grit sandpaper and light lubricating oil (3 in 1) and started polishing. I kept the injector sealing surface always pointed down so that any grit or debris wouldn't fall into the injector.
By the time I was done, the surface was polished and smooth - under the magnifying glass it looked very very good. Always keeping the polished side down, I swirled it many many times in a cup of kerosene. A fair amount of grit and debris came out. Kept doing it till I was satisfied nothing more would come out. Reinstalled the injector with a new heat shield, crossed my fingers, and started her up. Success!
Thanks again to ORCoaster. Neil
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Good to hear you were successful. Thanks for letting us all know what worked.
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Your welcome. Glad some of my ideers work some of the time. I figured it needing polishing to make what ever was causing the seal trouble to go away.