Dear Friends
Just finished a project that some may consider not respectful of car roots, but I just helped the customer to solve the situation created by previous owner.
This is the case of a W108-280SE fuel injected that lives in Dominican Republic. This car as lives in a place where not many mechanically fuel injected Mercedes specialist exist, so at some time of its history they decided to switch the originally FI M130 engine for a diesel OM617.
Of course actual owner of the car received the heritage of some engineering errors made during that conversion. And nevertheless the engine works, the control part of the pre-glow system and the engine shutoff system is failing.
At the beginning I though this was an usual w108 wiring harness restoration. The complexity came after once the owner told me about the w123 Diesel engine conversion.
The implementation of that engine conversion brought some new problems, as the heat generated by the turbo compressor which affects the performance of the original A/c system. On all w108 the refrigerant high and low pressure refrigerant hoses are run trough the right side of the engine. The proximity with the turbo generated and undesired excessive heat exchange. Therefore, to make it work it right, all components will have to be moved to the LEFT SIDE, and as a consequence the original A/c wiring harness has to be modified or remade. The later was the solution taken.
Originally the pre-glow system used on this conversion came from a w115 where the pre-glow plugs are connected in series. That was changed to the logic used on w123 300D from year 1980 up where a new kind of pre-glow relay is used that connects the new style (faster) pre-glow plugs in parallel.
A new instrumentation cluster that came from a w115-75 was included on the project which made me change the instrument cluster connector pin positioning (pin re mapping) to make it work properly. W115 from that year used electric signals for the temperature gauge, and also has a diesel glow plug light indicator.
The engine didn’t shutdown when turning engine to the off position, maybe because of a mis adjusting of the fuel cutoff cable, and customer asked me to give it an electric solution, so a Normally closed fuel cut off valve was added.
If you have a similar project on hands write me. I may help.
Best regards
L.Peterssen
