Test everything and keep the best. (Johann Wolfgang von Goethe)

An injector tester - of course you need something like that!
It's better to have than to be in need...

So if you've got yourself to the conclusion that life without a injector tester leaves a sense of imperfection behind, well, a Ching-Chang-Chung tester is available for about 80 EUR - ordered with a click on the internet. Certainly works too. But since the better is the enemy of the good, I was keen on an original Bosch tester - preferably one with two different pressure gauges.

The standard testers are designed for testing diesel injectors. They need several 100 bar opening pressure. However, the K(E)-Jetronic injectors of my Mercedes requires an opening pressure of just 4 bar. The commonly used pressure gauges are therefore too inaccurate to test the opening pressure.

After some time, a corresponding advertisement appeared on the market - exactly what I was looking for. Unfortunately, the device was in a pitiable condition - but apparently not defective and also complete, even the original manual in addition with a third pressure gauge was offered.

After the deal was closed, the parcel boy got a task. The seller has the unit packaged well and sent all parts as agreed. In my infinite generosity, I immediately disposed the dappled and spilled wooden board.

The tester got immediately disassembled and cleaned completely. I have provided the pressure gauges with a new seal and repainted the housing. The base housing I cleaned with a rotating brass brush. As a side effect, a thin layer of brass is applied to the material, which also serves as a corrosion protection. I parkerized the remaining parts.

I got all necessary seals, as well as the necessary Ermeto fittings and the Ermeto pipe from a local hydraulic specialist. In addition, I ordered a new injector for my '107 - using as a reference.

During assembly it turned out that a compression spring was missing inside. This was quickly bought at the Bosch service shop. Some parts of the tester are standard parts of old Bosch injection pumps and thus still available. The device works perfectly, as can be seen in my video. The total cost did sum up to 103 EUR in total.

I'm awaiting now more supple temperatures, in order to test the 8 injectors of my Mercedes.