Injector lifespan?

Is there a general consensus on what the typical lifespan of a fuel injector for a T1n is? A knowledgeable member told me his opinion was 200K miles. My van has 188K on it now, have very early, small black death symptoms, and no luck so far removing my first injector. Maybe it would be prudent to order new injectors and get ahead of the game? Thanks for your views. Van is vey clean, rebuilt trans, new tires, no real rust, runs great, good mileage, and I love it, btw.

Metal.
The injectors will last the life of the vehicle as long as you use genuine MB fuel filters. Eric.

I'm going to try to get mine to 500km (310k in freedom units). I'm 40k freedom units away. It doesn't idle as smoothly as some, and the STAR diag compression test says cyl3 is a bit lower than the others. But the injectors are all within spec on the smooth running test. My hot oil pressure is around 10psi. I also ran it for over a year with a dodgy head gasket and it is now "fixed" with chem-i-weld. So in 40k it will be even closer to rebuild territory anyway. So Eric is about right from what I've seen with my van.

Of course I've also seen vans with less miles than mine die from an overfuelling injector.
EDIT: and I've also seen vans die soon after having injectors replaced with "new" ones - which turned out to be dodgy parts.

Black death has nothing to do with injector lifespan btw.

After talking with a bosch injector tech, it seems many are well out of spec around 150-250k miles. At least in the USA. The USA has a slightly lower lubricity standard, and our diesel fuel varies quite a bit more than Aus or Europe does. Which affects injector life. If you continue to operate an injector past its life, you can expect poor idle, lower fuel economy, and louder operation. Eventually you will either see poor starting, low/high fuel pressure codes, or possibly sticking injectors. When an injector starts sticking open, or leaks from the main needle seat, it can destroy an engine by overheating the cylinder, and also by washing lubricating oil out of the piston/rings.

There are two main wear locations on these units. The first is the nozzle. This can cause poor injection pattern, and drift from specified volume/rate. The second is the ball seat which controls the pilot circuit. This is acted upon by the solenoid control fluid circuit, and actually triggers the injection event. Eventually the ball erodes the seat, and the injector can start sticking open. It can also cause excessive leak-back, which results in starting while hot issues. The latter can be tested for using a leak-back test. The former cannot be tested in-situ.

Using quality filters (4 micron) is important to injector health. But even with OEM grade filters, there is still the risk of fuel contamination. A handful of emulsified water contamination events can cut an injectors life in half. Emulsified water makes fuel cloudy, and even 1% dramatically reduces fuels lubricity.

As mentioned, black death injector is head seal leakage. It doesn't harm the injector, though sometimes the sealing face needs recut, and the injector can be damaged during removal.

I take my van to pretty remote places sometimes. So I plan to pull my injectors around 190k, and send them for testing while I am down for other maintenance. If they are marginal, I will have them overhauled.

A single example of injectors providing service is Ciprian's 2005. To my knowledge his injectors are factory at 770,000 miles. That included running with one injector unplugged to press on to a delivery, and then R&R of that injector for seal replacement.

Not passing OEM spec...
Anecdotally it seems to me that there haven't been many used injectors sent in for testing which pass muster. How perfect do they really need to be for general service?

An overfueling injector is a real concern. As Owner pointed out, that can be a problem even when injectors are renewed on a schedule. My guess is that there are more high mile Sprinters running on original injectors than there are those who have regularly replaced them as a maintenance item. Is that proper maintenance? It seems to work.

When I found Black Death seal leakage on my 2004 220,000 miles I replaced all 5 injectors with Bosch rebuilds... they didn't require a core return though, so maybe they were new. My present opinion is that it was an unnecessary expense. At 329,000+ miles now I would only repair what was needed. That will also be my mode with the 2006.

My opinion on injector preventative replacement.
If anyone does decide to replace their injectors I would be very careful to source proper Bosch injectors from a reputable supplier. Plugging in parts found on eBay may put you in a worse situation than you would have been in had you left the factory parts in service.

Sending the injectors out to a Bosch certified shop for testing and repair/replacement as MWD suggested is a safe option.

vic

I always fall back on the bathtub curve for failures. Though with the injectors it seems that the tail end is not as steep. For those with higher tolerance of failure events or downtime, it makes sense to wait until you have symptoms. Just don't ignore the symptoms when they present!

Midwestdrifter said:

I always fall back on the bathtub curve for failures. Though with the injectors it seems that the tail end is not as steep. For those with higher tolerance of failure events or downtime, it makes sense to wait until you have symptoms. Just don't ignore the symptoms when they present!

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It's a great graph. The trick is to apply the proper units to the Time (Miles) flat area of the curve.

200,000 miles has been mentioned, but is that accurate? An extra 50,000 miles (only 25% increase) could easily add 5 years service for some owners.

vic

I’d call up a shop such as Linden Engineering who has thousands, not a handful, of data points helping to create their view/opinion on the subject.

Having said that, my handful of data points (i’d say around 50 swapped injectors), point to to an average injector’s lifespan of efficient operation similar to what MWD outlined. Will there be outliers in both sides of the distribution, of course...

1 instance in swapping out all of my personal rig’s injectors with certified Bosch shop remans resulted in an over night increase in fuel economy of 12%. But is a 12% increase in fuel economy worth the ~$1,750 plus labor and potential risk of screwing up the job, perhaps the head???

I’ve had great success and seen dramatic improvements in smooth running and fuel economy by disconnecting the fuel tank, putting in an inline fuel pump to compensate for the in-tank lift pump (om647), and then running a couple cans of straight liquimolly diesel purge from a jug...

I tend to change my fuel filter each time I change my oil filter (about 7500 miles). Although the price of a good Mann filter has dramatically gone up recently, if you do it yourself, both filters and two jugs of good oil are still less than $100. I figure it is cheap if it adds longevity. What say ye about this practice?

Regards,

Mark

Changing that often has minimal benefit, and adds a small amount of risk due to accidental damage or introducing debris. I would say 15-20k miles is the shortest I was go.

There's no reason to think that the micron rating goes high as the filter service time increases. If anything it may improve. In my limited experience a 30 - 40k mile T1N fuel filter change intervals provide reliable service. Even MB has increased the fuel filter miles interval on newer Sprinter models.

I carry a spare fuel filter and the tools to change it. A bad load of fuel can quickly load up even a brand new filter.

vic

vanski said:

I’d call up a shop such as Linden Engineering who has thousands, not a handful, of data points helping to create their view/opinion on the subject.

Having said that, my handful of data points (i’d say around 50 swapped injectors), point to to an average injector’s lifespan of efficient operation similar to what MWD outlined. Will there be outliers in both sides of the distribution, of course...

1 instance in swapping out all of my personal rig’s injectors with certified Bosch shop remans resulted in an over night increase in fuel economy of 12%. But is a 12% increase in fuel economy worth the ~$1,750 plus labor and potential risk of screwing up the job, perhaps the head???

I’ve had great success and seen dramatic improvements in smooth running and fuel economy by disconnecting the fuel tank, putting in an inline fuel pump to compensate for the in-tank lift pump (om647), and then running a couple cans of straight liquimolly diesel purge from a jug...

Click to expand...

Fabulous.
Can you tell me what I need for the pump mod?

Thanks for all the input. If I were to pop for replacement injectors my choice would be brand new oem parts, makes no sense to take the chance with rebuilt ones in my mind. As great as my van has been running, I think I will leave well enough alone for now, except for changing all the sealing washers, which my van needs done, but that is another story. yes, I read all 24 pages of that thread!! First one I tried is not budging...

skwoodwiva said:

Fabulous.
Can you tell me what I need for the pump mod?

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I picked up a 60 psi fuel pump from Summit Racing...

You need a bunch of fuel hose, I want to say 1/2" diameter, but do that research. i believe you need two different diameters..

A bunch of hose clamps.

OF COURSE MAKE SURE YOU'RE PUSHING THE LDP THROUGH THE FUEL FILTER PRIOR TO THE FUEL INJECTION SYSTEM. i know this goes without saying, but for anyone trying this i want to make sure..

also, you're disconnecting the return line and putting it back into the jug..

vanski said:

I picked up a 60 psi fuel pump from Summit Racing...

You need a bunch of fuel hose, I want to say 1/2" diameter, but do that research. i believe you need two different diameters..

A bunch of hose clamps.

OF COURSE MAKE SURE YOU'RE PUSHING THE LDP THROUGH THE FUEL FILTER PRIOR TO THE FUEL INJECTION SYSTEM. i know this goes without saying, but for anyone trying this i want to make sure..

also, you're disconnecting the return line and putting it back into the jug..

Click to expand...

This is a great idea, did you get a pump specifically for diesel, or are the gas ones OK to use for this short application?

They are.

my thought was diesel has more lubricity than gas, so any gas pump would work fine... perhaps not? so far so good.. the PSI is what's important for the correct compensation.

Midwestdrifter said:

As mentioned, black death injector is head seal leakage. It doesn't harm the injector, though sometimes the sealing face needs recut, and the injector can be damaged during removal.
.

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In my opinion and no disrespect meant as it is a laymans view.
Injector overfuelling may contribute heavily to black death seal leakage
the excess fuel could easily be causing higher pressure within the chamber than was designed by MB. I dont know the compression numbers air vs diesel but I would GUESS diesel is harder to compress and therfre add stress to the hold down fastners

would be interested to see some numbers if anyone is inclined.

It seems a lot of people get overfueling injecter one and also seems to crop up as the first sign of black death.

of course thats all anecdotal and uninformed hearsay
Grumps

grumpy-old-van said:

In my opinion and no disrespect meant as it is a laymans view.
Injector overfuelling may contribute heavily to black death seal leakage
the excess fuel could easily be causing higher pressure within the chamber than was designed by MB. I dont know the compression numbers air vs diesel but I would GUESS diesel is harder to compress and therfre add stress to the hold down fastners

would be interested to see some numbers if anyone is inclined.

It seems a lot of people get overfueling injecter one and also seems to crop up as the first sign of black death.

of course thats all anecdotal and uninformed hearsay
Grumps

Click to expand...

A counterpoint to the above is that many, many times an injector position with Black Death seal leakage is repaired by properly replacing the seal and re-installing the removed injector. The injector and repaired position perform properly from that point on.

vic

I have my doubts. Given that seal failures are less common in arid environments, and that they tend to occur on the 1st cylinder. I believe the evidence supports a corrosion based primary failure cause. Any over-fueling significant enough to cause seal failure is also likely to damage pistons/heads.

In my case the failure was around 140k miles, on injector #1. No other symptoms except exhaust smell at low speeds and high loads.