This can be installed in your W116 W123 W126 W201 W124 diesel in 60 to 90 minutes. You will use the video instructions for installing it in a W123 (included), then you will make location modifications to fit your specific chassis. It is not possible for us to show the individual installation in every single model. Use your creativity and install it the way you want! Watch Kent's YouTube video below, and he will show you the installation variables.
Product Details
NOTE: These special kits are assembled to order. Please allow 3 to 5 days before expecting it to be shipped. Kent first learned about the advantages of using a low-pressure fuel boost pump on an old diesel when he was converting those engines to run on straight vegetable oil. Want better starts, more power, easier fuel system maintenance? Watch the YouTube video below for a demonstration and full explanation.
As of 8/14/25, the kit will now come with ONE relay and ONE switch installed. A second relay and switch can be purchased separately and can be added to the existing aluminum panel in just minutes. This could be used to power a fuel boost heater for SVO operations, or some other electrical component of your choice. Note these are advanced relays with fuses built in for added safety.
Here is where the switch panel is best located in a W123 diesel.
The front left side of the false firewall makes a good location in the W126 and W124 diesels.
The kit comes partially prewired and assembled, 90 percent ready to install. This will save you one to two hours of time, depending on your electrical wiring skills. There is no cutting into the original wiring, and you only need to drill three small holes in the left side inner fender panel ( you could glue the parts on with E6000 if you did not want to drill and remove the parts later). DSLBOOST
It will be easy to add an additional toggle switch and relay in just minutes without and drilling. See related products below to order separately.
Included are the following wiring connections and hardware. This will cover most of what you will need to complete the installation unless you choose to do extensive modifications.
Extra-long battery wire, 5/16 inch fuel hose, and extra clamps are included, providing enough for almost any installation.
The entire installation installs in the engine compartment with easy access. You will not need to work in the back of the car nor will you need to raise it up.
Related Products:
Fused Relay and Toggle Switch Combo
The new switch fits perfectly into the hole already drilled and all you need to do is tighten it down. The relay slides onto the side of the other relay and locks in place. It is not necessary to attach it with another screw.