Mercedes injector pipe part numbers: which number fits which vehicle series?

An injector pipe for a Mercedes-Benz is ordered by its ten-digit part number, not by the vehicle series name: of the 63 numbers we took from our product list for this article, 39 are matched to one truck series. The same number may be written with or without a leading A, with or without spaces. The table below gives 15 numbers and the vehicle series they fit: mostly trucks and buses, plus the Sprinter, the Vito and a few diesel cars.

How is a Mercedes-Benz part number written?

All 63 Mercedes-Benz injector and common-rail pipe numbers we examined have ten digits, but they are written four different ways: A 906 070 14 33, A 6460700333, 6460700233 and 346 070 0133. Some carry a leading A; some split the digits into groups. One entry shows the same number both ways: A6110701133 / 6110701133.

When you search, type the ten digits without spaces first. If nothing comes up, add the A or split the digits into groups of three, three, two and two. The suggestion is ours; it rests on the TecDoc web service definition, where a number search defaults to “exact: Exact Match (DEFAULT)”.

Only one entry in the list names an engine: it begins with 651 and its description says OM651. All eight numbers beginning with 366 are matched to the Unimog and the OF, L, NG and OH series. These are observations, not rules: we could not confirm what the letter and the digit groups mean from a Mercedes-Benz document we are able to use. Do not read an engine name off the first three digits.

Where do you find the number?

If you already have a number (old pipe, box or invoice), copy it digit by digit. If not, it is found in the vehicle maker’s parts catalogue through the chassis number (VIN). Which numbers sit on a part, and how a catalogue is searched, is covered in our article on OEM part numbers.

In the EU this search is written into law. Annex X of Regulation (EU) 2018/858 covers the parts fitted to a vehicle “identified by the VIN” that can be replaced by spare parts the maker offers by reference to an OE parts number. Information on them must sit in a database “easily accessible to independent operators”, a term that includes repairers and the makers and distributors of spare parts. The Annex says what the database holds:

“This database shall comprise the VIN, OE parts numbers, OE naming of the parts, validity attributes (valid-from and valid-to dates), fitting attributes and, where applicable, structuring characteristics.”

Regulation (EU) 2018/858, Annex X, point 6.1; 30 May 2018

Independent catalogues are searched with the same OE number.

Which number fits which vehicle series?

The table gives 15 numbers and their compatible vehicle series, written without the A and in groups of three, three, two and two digits.

Brand names and OEM reference numbers are used for identification and compatibility information only.

The table was selected from the numbers in RSS Kumru’s product list that have been verified against two independent sources. In the list the L Series carries the years 1960–2011, the NG 1973–1998, the SK 1987–1996 and the MK 1987–2005. Three dots mean the entry gives no end year.

Not shown: the entry for 611 070 11 33 also names the Sprinter, the Viano and the Vito, and the entry for 651 070 24 33 names 18 series.

Why does one vehicle series have so many numbers?

Because a series name does not point to one pipe. Of the 63 numbers we examined, 39 are matched to the NG Series, 33 to the SK, 31 to the MK and 30 to the L.

Bosch’s Diesel Engine Management gives one reason: “All cylinders are fed by high-pressure delivery lines of a single, uniform length”, and bends in the lines “compensate for the different distances between the outlets from the fuel-injection pump or rail, and the individual engine cylinders”. Each cylinder’s pipe is therefore the same length but a different shape. Line dimensions also “vary according to pump size”. The book says nothing about part numbers; that every shape or size of pipe carries its own number is our conclusion.

Do not read cylinder order into consecutive numbers. Five numbers run in sequence from 422 070 6333 to 422 070 6733, but which goes to which cylinder is for the vehicle maker’s catalogue to say.

What if one pipe is listed with two numbers?

Search with both. In our list, the description of the common-rail pipe 651 070 24 33 gives two numbers: A6510704233 / A6510702433. We have not read a manufacturer’s record showing which is the older and which the newer, so we do not rank them.

One number taking the place of another is an ordinary catalogue record: TecDoc’s search types include both a “Replacement Number” and a “Replaced Number”.

What if the number cannot be read or the pipe is no longer made?

A pipe whose number cannot be read is described by its measurements; see our article on describing a pipe without a number. If the number is known but the part can no longer be had, see our article on having a discontinued pipe made from a sample. With a number in hand, we suggest this order:

1. Write down the digits. Read all ten; do not guess a missing one.
2. Do not stop at the series name. Ask only for an NG Series injector pipe and 39 of the numbers we examined fit.
3. Add the chassis number. The vehicle maker’s catalogue shows whether the number belongs to that vehicle.
4. If there are two numbers, give both. When you take the old pipe off, mark which cylinder it came from.