This tester is specific to K-Jetronic V8 engines due to the special fittings and adapters it includes. These included M116 and M117 engines in the W116, R107, and early W126 chassis. The tester itself may work with other Bosch CIS fuel injection systems, but the included fittings to attach the hoses to the engine will most likely not work. Kent believes strongly in doing the tests with the engine NOT running, so he has developed two special jumper leads to allow you to do just that..
Product Details
The kit includes the following:
- CIS fuel injection tester with a multi-function shut-off valve
- Correct fittings to attach to the fuel distributor and the WUR
- Jumper leads to run the fuel pump with the engine off
- Jumper leads to heat the WUR without running the engine
- Thin 14mm wrench for attaching the tester fittings
- Special hose for completing the fuel flow test
- Video instructions
The included video instructions will cover hooking up the tester, running the tests, theory of operation, diagnosing the warm-up regulator, and a link to other resources Kent recommends to help you repair the problems you may discover.
FOUR EXTRAS will be included with this kit to increase the ease and accuracy of your tests.
- 12-volt power test lead for the warm-up regulator
- Hose and fitting to attach to the fuel distributor for the fuel flow test
- Short switched jumper lead to use on the W116, W123, and W126 with a relay near the firewall.
- Long 5-foot jumper lead for the fuel pump relay in the R107 ( relay is behind glove box ).
Do you have more than one Mercedes requiring different pressure testers? Are you not sure which one to order? Be sure to check out my ALL-IN-ONE kit that will test almost everything from the early 1970s to the late 1990s. See the related products below.
The stainless steel gauge is liquid-filled, which provides better accuracy, as well as protects the sensitive mechanism from abuse. Do not rest the gauge on the engine while testing; hang it off the engine somewhere in the engine compartment for viewing. Note that the gauge is not full of liquid, and that is normal. There must be some air in the gauge to allow the needle to move freely.
Kent has eliminated the quick-disconnect fitting at the tee on the lower hose. Quick-disconnect fittings have proven problematic over time. You will still be able to disconnect the gauge. When you screw it down onto the long hose, tighten it only finger-tight; do not use a wrench or pliers, or you'll damage the seal.
Regarding the bottle attached to the tester. This is to allow you to release pressure and fuel from the tester BEFORE you disconnect it from the engine. Please keep the bottle upright while doing this, as there is a very small hole under the cap that allows the bottle to vent pressure. If you lay the bottle on its side, it can leak fuel out very slowly.
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