First off, howdy all, as this is my first post, after lurking a bit, and reading/searching around. This looks like a really active forum, with lots of knowledgable folks contributing.

Background: I am a relatively new fan of diesels, and merc diesels in particular. A friend of mine converted an 85 300TD to run SVO, and got me hooked. We are both "project car" type thinkers, so we jumped at a chance to buy a package deal from a local seller: a very rusty and not-PA-inspectable 77 240D with a 4 speed manual and a working but slightly tired engine, and an 83 240D with an automatic trans, and a rebuilt-but-not-finished engine, with over $1000 worth of machine work into the engine. The seller had already done quite a bit of tear-down on the 83 chassis, including taking the doors apart to figure out the vacuum locking problems, and why the electric windows weren't working. The entire engine bay had been emptied out, and the rebuilt core of the engine (sealed up and rebuilt from oil pan to valve cover, but needing all other parts put back together) put back on the mounts. We don't have any contact with the seller any more, as he moved, and we have lost track of him.

Money is drum-head tight for both of us, so we decided to transplant the working 77 engine into the 83 body, get it running, drive it for a while, and finish the work on the rebuilt 83 motor, and eventually transplant it back into the 83 body. We parked the cars side by side, and found a few differences, but nothing that seemed critical enough to stop the project.

We have successfully transplanted the 77 motor into the 83, and have things running and driving.

However, a few issues remain. Here is a list of all the problems, and a bit more information to go with them. I don't know of these are individual problems, or all tied together.

1. No brake lights when pedal pressed (tail running lights, turn signal lights, and backup lights all work properly)
2. No fog lights (At least one of the bulbs is known-good, and headlights work fine, high and low beam)
3. Fuel gauge registers empty, and no reserve warning light (bulb checks okay though), with a 1/2 tank of fuel
4. Temp gauge doesn't register any temp, even with engine at normal operating temps, and thermostat cycling normally

We haven't figured out the vaccuum locks, or the electric windows, but we haven't even started to evaluate them. the vaccuum system seems to be working okay, as we have no trouble shutting off the motor, and the HVAC system (Well, minus the AC portion) works fine.

Here is my "big clue"... There is a 14 pin connector hanging free under the drivers side dash. The car was equipped with cruise control, but there appears to be only one "large silver box packed with electronics" under the drivers side dash, and it is already connected, with a 10 or 12 pin connector. Am I missing some kind of relay or control module that would tie all these problems together? I have checked the more obvious stuff, like connections behind the dash, bulbs, fuses, clean accessable connections. The charging system seems to be working fine, running at about 14.02v , and the battery is new.

Whew. Okay... I can answer any more questions you have, and would welcome advice and input on trouble shooting things.

-Matt