items to fix on 1980 300D

ahoy:

i've had a 1984 300D Turbo for several years (270k mi.), but the transmission blew and it didn't seem worth fixing. i purchased a 1980 300D (not a turbo). the 1980 (101k mi.) needs some repair, but has a very good engine and transmission.

i'm assuming that the repairs to the 1980 are much less than having its transmission put into the 1984 and am interested in getting the best of both cars into one.

the major problems with the 1984 (turbo) are: transmission need rebuild or replacement light combi switch bad body rust

the 1980 problems are: climate control not working odometers, clock not working, speedometer reads (~15%) low. antenna/motor not working

[] i'd like to get the speedo/odo repaired. what is the best way? [] can the climate control from the 1984 be transplanted into the 1980? they have different dash panels. in the 1980 climate control, the defroster fan works, but no fan works in any other positions. is there something to look for to repair this?

thanks in advance,

-rr

The climate control is in its default mode - defrost.

The 1977 - 1980 climate control systems are horrible, complicated and expensive to repair (excluding the a/c). There's an "amplifier" logic circuit board behind the glove box that cracks and causes the system to act crazily - sudden full heat etc. These are sold rebuilt for about $100.

Then there's the "servo" nested on the right fender, it controls the heat, fan speeds duct openings etc. These are no longer available new and sold as rebuilt for about $500.

Having lived with this crap for about 20 years, a few years ago I installed a digital retrofit system in my '80 300SD and am satisfied with its performance. It replaces the servo and amplifier and preserves the original appearance of the climate control panel in the cabin.

formatting link

is the manufacturer's site, they show a '80 300CD installation. The kit may also be available on e-bay.

Do a Google search for "speedometer repair and Mercedes" to find a shop. Correct tires are 195/70-14, others will distort the speedometer's reading. Usually, these speedos were 10% fast. Given that a clock is also needed a junk yard cluster may be something to consider. There are odometer gears available as well if you want to DIY.

Antenna motor may be disconnected or broken. I'd just pull the antenna up about 20 inches and disconnect the motor.

The big decision is the climate control, the other items, each though small, will probably add up to that amount as well, but then you have a car that's 100%.