I just bought a big 240 tach and clock off of e-bay that was advertised Tach an "Upgrade Kit for 240 1981-93" in "good working condition." The seller has 100% positive feedback, so I bought the kit with confidence. I attempted to install both instruments today. . .the clock is wired up and working, and the tach fits perfectly in the dash. . .but it's not working. Since purchasing the kit, I've discovered that there are two different part numbers for '81-'88 240 tachs vs. '89-'93's, but they look identical.

So. . .is it just that the an '86 won't work in a '92, or could it be something else - perhaps my install? I followed the simple instructions I found on the Board, but I guess I could have overlooked or screwed something up in the process. Please help! Thanks!

Yes they work. I have one in my 89 244.. just unplug large clock from dash and plug the tach in its place.over all the pins that stick out,, and find the white/red wire and connect it to the lower spade terminal on lower part of tach,, not on the 3 prong spade terminal...that is where the light and power go to the new smaller clock you might want to install in one of your now blank places next to the radio...
--
Max..1989 244 DL 5 Spd., Bilstein HD, Turbo Swaybars, Poly Bushings all round, Turbo Wheels, Black leather interior, Electric mirrors, LED dash and gauge lights.

As noted the only difference should be the faceplate, and it's minor.
Satin vs. flat? Yeah, big deal.
I've used 1983 tachs in a 1991 car and everything was fine. However- the day I did that, I thought I did something wrong. I put it together, having never had a problem installing or removing a tach, and NOTHING WORKED. A few lights were on dimly and the I seem to remember the speedometer hovering at a low number- car not moving.
Hmm. Weirdness. REmoved everything and started over. Obviously I got a connection on wrong. There are a few loose wires on the back of the panel, for things like the SRS and ABS lights I believe, that are not in the earlier cars. In any case, the second time I connected everything and double checked it all, the tach worked fine and has ever since.
The white/red wire goes to the double terminal on the bottom of the tach, and the other pins are for the accessory wiring harness for the small clock, if you installed that.
I'm convinced that somehow I got a ground wire on wrong, but I can't guess where. Related subject, I just worked on a 740 speedometer ABS signal converter- and guess what? THe speedo wiring harness provided the ground for the whole panel. Who knew? Very weird behavior with that wire unhooked, believe me.
Good luck with it.
--
Rob Bareiss, New London CT ::: '87 244DL/M47- 230K, 88 744GLE- 220K, 82 245T-181K Also responsible for the care and feeding of: 88 745GLE, 231K, 87 244DL, 239K, 94 855GLT 189K

The clock gets its power (and lighting) from the plug on the back of the tach, so if it's working, the tach is plugged properly into the instrument cluster board...ie: it has 12V and ground.

The only thing left is the signal from the coil. This is prewired into all cars (I think...certainly is in our 240's) and is a red/white lead behind the cluster. Sometimes covered in a gray sheath. Maybe different color in your "late" 240.

If you have found it, plugged it in to the male spade on the lower rear of the tach, and still no joy, run a long jumper lead from the coil's No.1 terminal into the car and connect that to the tach male spade. Works?..bad or wrong wire behind the cluster. Doesn't work?..Bad tach.

I check junkyard (which is where the eBay sellers get them) tachs by connecting them to battery and coil in an underhood test before installation. So far, all have been fine, so hope yours is too.
--
Bob (son's 81-244GL B21F, dtr's 83-244DL B23F, 'my' 94-944 B230FD; plus grocery-getter Dodge minivan, hobbycar MGB, and numerous old motorcycles)

There are two tachs. One satan black on the older 240's and one flat black on the newer ones. I'm almost positive they are interchangeable.