SilverWagon
Veteran Member
I assume you mean by the mechanic, not the injector rebuilder?
Investigating Diesel Smell
- Thread starter SilverWagon
- Start date
SilverWagon
Veteran Member
I described the leak wrong. It's only coming from the top of 2 of the injectors ; between the hard line and the injector. The mechanic says there is no seal between the hard line pipe and injector. It's a compression clamp.
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jmodge
Top Post Dawg
- Joined
- Jun 18, 2015
- Location
- Greenville, MI
- TDI
- 2001 alh Jetta, RC2 w/.205's 5speed daily summer commuter and 2000 alh Jetta 5spd swap, 2" lift, hitch, stage 3 TDtuning w/.216's winter cruiser, 1996 Tacoma ALh
That can happen after they've been overtightened and creased on the bevel. I have cleaned them up by hand with some light filing or stone work. Polishing more or less, they need to be cleaned well afterward so nothing ends up in the injector. Sometimes it's only a matter of slightly rocking them as you snug the nut to bed them in by feel.
Steve Addy
Top Post Dawg
Right, there is no seal between the hard line and the injector, the line has a bulbous end that fits into the cone of the injector on the top.
The leak at this fitting suggests that either the hard line is warped from having been cranked down too tight at some point OR the injector surface has a blemish(es) that weren't dealt with by the injector rebuilder.
Mechanic needs to determine whether the fault is injector or hard line. My guess is it's likely the hard line but since I can't see it I can't say for sure, but typically that's where the problem shows up.
Steve
KrashDH
Top Post Dawg
There's no sealing washers on the hard lines.
The sealing washers are for the injectors.
There's also a specific way to tighten down the rockers to ensure sealing too. If the sealing washers had a burr, it could cause the injectors not to seal. I have seen that.
Edit: ignore this paragraph as you said you pinpointed the leak at the hard lines.
As I mentioned, white smoke usually points to an injector flowing too heavy/leaking. You're dumping extra raw fuel into the cylinder. When you start, it all gets pushed out the tailpipe unburnt.
Agree with above that the lines could have been overtightened. That will gouge out the interface between the line and the injector seat potentially
What do your injector contributions say in VCDS?
PakProtector
Veteran Member
The seal is steel-on-steel, line contact between two surfaces of differing radius. It is pretty hard to ruin, but it seems to me that who ever put them back together last managed to do it improperly.
Douglas
Gothmolly
Veteran Member
If you're smelling raw diesel, check the rubber low-pressure lines that link the injectors. They dont last forever.
KrashDH
Top Post Dawg
My technique for hard lines is while they're loose, I'll wiggle the line as I tighten up the nut so it naturally seats. When it's hand tight it should be seated properly then I'll torque to spec. If seated properly you really don't need a lot of torque on the line nuts. Snug with a little extra turn.
KLXD
Top Post Dawg
What Krash said.
Nuje
Top Post Dawg
- Joined
- Feb 11, 2005
- Location
- Island near Vancouver
- TDI
- 2002 Golf 6MT; 2015 Sportwagen 6MT; 2016 A3 e-tron 6DSG
Torque spec is 25Nm (18ft-lb) on those compression nuts that hold the hard line to the injector. Anything much more than that to get it to seal and something is dinged up.
If you don't have a good torque wrench, envision a 20lb dumbbell at the end of a 1ft. bar - it's not nothing, but at the same time, it's wrist/forearm, not bracing yourself and putting your back into it.
If you don't have a good torque wrench, envision a 20lb dumbbell at the end of a 1ft. bar - it's not nothing, but at the same time, it's wrist/forearm, not bracing yourself and putting your back into it.
KrashDH
Top Post Dawg
Most people don't have the right attachment (crows foot or fuel line) to connect to a torque wrench. Plus it's hard to get enough swing in there with most torque wrenches to get them to catch because of the degrees of engagement unless you have a very high end wrench.
The other thing to be wary of is where the wrench attachment is in terms of length relative to the torque wrench drive. You have to reduce to torque if you're out further, there's a calc for it.
Nuje
Top Post Dawg
- Joined
- Feb 11, 2005
- Location
- Island near Vancouver
- TDI
- 2002 Golf 6MT; 2015 Sportwagen 6MT; 2016 A3 e-tron 6DSG
Right - good point.
I was just trying to give a frame of reference of what the correct torque is - like, if you're bracing with one arm and pulling with your whole arm to tighten and it's still leaking....don't tighten more thinking it's gonna fix things.
I was just trying to give a frame of reference of what the correct torque is - like, if you're bracing with one arm and pulling with your whole arm to tighten and it's still leaking....don't tighten more thinking it's gonna fix things.
SilverWagon
Veteran Member
Update: I found some aftermarket injector pipes from kbdieselperformance.com . I paid under $145 for a full set through Amazon. I received them today and they look identical except for the clamps that hold them in pairs.
I spoke with the mechanic today and he said he wasn't sure why 1 and 2 were slightly bleeding fuel but the metal looked pitted. He said that's uncommon for a California car. My vehicle is from the midwest and due to the weather there he suggests that might be the reason they were leaking. I'm not sure why the metal touching metal would become an issue if they were creating a seal unless junk is in between the injector and pipe.
Tomorrow the mechanic will put them on while I wait. I'm going to take a look at the original pipes before the new ones are put on and look at the injectors.
I spoke with the mechanic today and he said he wasn't sure why 1 and 2 were slightly bleeding fuel but the metal looked pitted. He said that's uncommon for a California car. My vehicle is from the midwest and due to the weather there he suggests that might be the reason they were leaking. I'm not sure why the metal touching metal would become an issue if they were creating a seal unless junk is in between the injector and pipe.
Tomorrow the mechanic will put them on while I wait. I'm going to take a look at the original pipes before the new ones are put on and look at the injectors.
KrashDH
Top Post Dawg
Like we said...if they are overtightened then the metal will gouge the mating side. Once that happens, it's pretty much game over if you loosen and then try to re tighten them.
Damn. I went pretty tight on the line nuts when I replaced my IP. They aren’t leaking, but now I’m worried because I’m planning on doing nozzles….
KrashDH
Top Post Dawg
Depending on the damage if there is any, you could hit the mating surfaces with emery cloth to ensure the burrs are gone. This would give a better chance to seal successfully if there's any gouging...just have to see when you pull them.
SilverWagon
Veteran Member
So, the mechanic put the new lines on. They didn't have a tool that could fit to get 25Nm. After he swapped the lines I drove the car for half a mile and popped the hood. They didnt seem to leak from the lines anymore but I did notice something else. At the bottom of the #4 injector, where the injector is touching the engine, bubbles were coming out.... They swapped the seal with a new one and it continued.
The injector will be going back to Becs Pacific to be looked at again. They said it's under warranty. It never ends and I'll be staying in this trailer park of town for another holiday.
The injector will be going back to Becs Pacific to be looked at again. They said it's under warranty. It never ends and I'll be staying in this trailer park of town for another holiday.
KrashDH
Top Post Dawg
Sounds like your mechanic is not properly "seating" the injector...
P2B
Top Post Dawg
+1
Seating surfaces need to be spotless. Sealing washer needs to be new or freshly annealed. Injector needs to be seated using a slide hammer - the hold down clamp is just that, tightening it does not create a seal.
KrashDH
Top Post Dawg
Gothmolly
Veteran Member
KrashDH
Top Post Dawg
You are a small data point in the large scheme of injector swaps. For some, they can tighten down and it's good
For others, it doesn't work like that. Countless evidence of people having leaks at those washers, then they use a method as described and the don't leak any more.
So it's situation dependent. These cars are the first ones I've seen that has a mechanism (rocker) that's purely a hold down. On most sealing washers interfaces, you torque a bolt head or something similar into the washer which deforms it and creates the seal. These hold downs don't put even pressure across the injector. So some need some "persuasion" to create the deformation and seal, especially since the torque applied is not in line or right at the interface
P2B
Top Post Dawg
Car will indeed run fine with slight compression leaks at the injectors, but it's best not to let them seal themselves with soot as it wiil take a BIG slide hammer to get them out
Sorry, but I find this thread painful to read and a real facepalm experience.
I'm still not clear whether the OP is smelling raw diesel in the cabin from either a leak in the engine compartment or the top of the fuel tank, or a diesel exhaust smell from a leak in the exhaust piping. I can tell you one thing for sure though, a leak from an injector at either the seat or the hard line fitting didn't just spontaneously occur in a car that's been running for thousands of miles unless somebody not competent jacked with it. From my experience, nine times out of ten a fuel leak under the hood is related to the original braided fuel return lines. Now.....you don't have a clue what the original problem was but I'll bet it was something butt simple.
The beauty of the ALH is in it's simplicity, compared to working on a lot of other modern cars it's like working on a lawn tractor. A lot of shops want to act like and charge like they're repairing a Beechcraft King Air. Just because the shop you take it to has name recognition doesn't mean that the guy they give it to is competent........especially in this job market. If you don't have the time or inclination to do your own maintenance and repairs or a relationship with a mechanic you trust.......trade it in for a Honda or Toyota. There's plenty of shops that work on them and they will compete for your business.
SilverWagon
Veteran Member
I forgot about this thread so I thought to give it an update to finish it off. The diesel smell is no longer present. I believe the smell was coming from the injectors and/or the hard lines allowing minute amounts of diesel to come out and vaporize when the engine warms up. The reason I think this is because I remember dust and debris around the injectors looking a little damp as if oil had made it that way. I thought maybe I had spilled some oil when doing an oil change and it had settled around the injectors. I should have touched it and smelled it to make sure.
I can't prove my theory but here's my reasoning. The injectors were rebuilt, the hard lines were replaced, the vacuum hoses to the injectors were replaced, and the IQ was lowered. The lowering of the IQ was done before the others and the smell was still there after lowering it.
I think the hard lines were not installed correctly so it's hard to say that was the culprit or just incompetence. The injector that was leaking was taken apart again and tested further but Becks couldn't find a problem. Luckily that was covered under warranty but the shop I was using charged me another $135 to put the injector back on. I was surprised at the time they would charge me for that but I shouldn't be since they were trying to charge me $1600 for a used injection pump they thought was the problem.
All seems to be working fine. The injectors are definitely louder. I found more problems with unrelated symptoms like a damaged ball joint, stripped threads in the wheel hub, all vacuum hoses were brittle, and the dogbone needed to be replaced. A small puff of white smoke and a random hard start still exists. Although, with the new engine mounts the hard starts are less noticeable. I wish there was a guru in this village.
I can't prove my theory but here's my reasoning. The injectors were rebuilt, the hard lines were replaced, the vacuum hoses to the injectors were replaced, and the IQ was lowered. The lowering of the IQ was done before the others and the smell was still there after lowering it.
I think the hard lines were not installed correctly so it's hard to say that was the culprit or just incompetence. The injector that was leaking was taken apart again and tested further but Becks couldn't find a problem. Luckily that was covered under warranty but the shop I was using charged me another $135 to put the injector back on. I was surprised at the time they would charge me for that but I shouldn't be since they were trying to charge me $1600 for a used injection pump they thought was the problem.
All seems to be working fine. The injectors are definitely louder. I found more problems with unrelated symptoms like a damaged ball joint, stripped threads in the wheel hub, all vacuum hoses were brittle, and the dogbone needed to be replaced. A small puff of white smoke and a random hard start still exists. Although, with the new engine mounts the hard starts are less noticeable. I wish there was a guru in this village.
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