84 300DT Questions - PeachParts Mercedes-Benz Forum

jerryyoung · #1 07-09-2003, 11:21 AM

Have a couple of questions - my owners manual shows a cruise control switch (stalk) on the upper left side of the control column. I don't have one there:eeK:! I checked the engine compartment and there is a cruise control servo mounted on the upper LH forward part of the engine. All controls (rods, electrical connector) are hooked up. Did some of these cars come without cruise and possibly someone has changed the sreering column for some reason? By the way, my ignition key and door keys are different, I thought they are supposed to be the same. Does the cruise control switch handle come out of the column in the same area as the combo switch handle?

Some more info on the car - I had an oil leak when I got to Fort Worth, discovered it was coming from the turbo oil return line, didn't have the "O" rings plus we couldn't figure out how to get the drain apart to change them (we disconnected the drain from the turbo, still couldn't get enough room to get it out). We put some sealant on the slip joint areas that my Son uses on the Ford diesels and now I only have an oil leak about the size of a quarter overnight

. As far as I am concerned, that's no leak!

Car still runs great, no smoke at all, oil level staying in same place, did I mention I like this car?

Thanks for all help.

Thomaspin · #2 07-09-2003, 11:38 AM

Disparate ignition and door keys suggests someone changed one of these at one time and did not use a matched cylinder. Determine which is the odd one out (I assume your passenger door has a lock also), take your registration card to the dealer and have him order the matching lock for your VIN. Lots of info on this site how to replace these.

As for the cruise stalk, it exits the steering column on the left behind the directional indicator stalk. Is there an orifice there with a rubber flap where the stalk would ordinarily exit?

#3 07-09-2003, 12:31 PM

I have seen the cruise control handles break off. There is a slit in the rubber covering the switch. Probe through the slit in the rubber to see if there is a switch in there.

Good luck,

Rick Miley · #4 07-09-2003, 12:59 PM

The cruise control stalk of my 1980 240D was also broken off when I bought it. The one in the 240D I spotted at the junkyard was also broken. But I managed to spot one in the back seat area of a 300D that was almost completely gutted.

On my W123, the cruise stalk is mounted in front of (closer to the driver) the turn signal lever. There is a rubber flap that covers the switches and has a slit that looks something like this:

O-----o

The larger circle is for the turn signal lever, while the smaller one is for the cruise control stalk and is easily missed. That rubber flap pulls right off with very little effort. Hopefully, yours will be similar and this will be useful.

jerryyoung · #5 07-09-2003, 03:20 PM

Thanks for the info, guys!

Thomas - I haven't checked yet to see which key is the odd one out, I suspect it is the ignition key as it looks newer than the other key. I will check tonight. I don't have a data card for this car, I think I can get one from MB?

Larry, Rick - Yes, there is a slit as you described in the rubber cover on the steering column. I popped it off last night and thought something didn't look right but wasn't sure what I was looking for. I will look again tonight and see what is there. I know where there are a couple of 240D's that may have good switches, also am going to look for good seat(s).

Thanks again, this forum is a gold mine of info

!!

Rick Miley · #6 07-09-2003, 04:53 PM

Good luck finding seat switches in a 240D. That would be extremely rare!

I replaced the key switch in my 240D with the correctly coded one from the dealer a few weeks ago at a cost of $109. It only took a few days for the tumbler to arrive. They will ask for a matching driver's license and registration to prove that you own the car.

Thomaspin · #7 07-09-2003, 05:03 PM

I think all you need is the VIN - that's what I gave them when replacing the ignition key and, later, the passenger lock after some schmuck tried to break in to my 1983 300SD with a screwdriver, disabling the lock. In La Jolla, of all places. Lots of crooks in nice places....

Installing a new cruise stalk s/b fairly easy, but you will have to take the steering wheel off to get at the plug. On my 1983 300SD the wheel is retained with a 10mm hex head bolt and the factory uses blue Loctite on the threads, so it can be quite tough to undo - use a long extension or, better, an impact hammer if you can get one as that places far less stress on car and operator. The steering wheel pulls straight off on a splined shaft - make a note of its relative position before removal to ease accurate reassembly. If you have an airbag, there's a few extra steps - please ask if you need help.

(Rick - I think Jerry may be referring to the cruise 'switch' not a seat switch).

Rick Miley · #8 07-09-2003, 09:27 PM

Yes Thomas, I think I read that wrong.

On the W123 you don't have to remove the steering wheel to replace the cruise switch. Once you remove that big rubber cover, the whole assembly comes out with two screws. Then you can separate the cruise switch from the turn signal switch. If you disconnect the wires from the apmplifier (mounted to the underdash panel) that will make it easier.

jerryyoung · #9 07-10-2003, 11:12 AM

OK, checked to see which key is the odd one - it's the ignition as I suspected. At $109, I may go with what I have for a while. Also checked the cruise switch area and sure enough, the handle is broken off right at the switch. Will search the U-Pull-It yards for a replacement.

Ya'll are going to get tired of me but have another question - I can't hear my turbo spinning up. The car seem to have good power, I don't get a "kick" from the turbo like I used to in my Shelby Charger, that little rascal would put the seat in your back when it kicked in! I guess the best way to be sure the turbo is operating properly is to plumb in a boost gauge and see what's happening?

My central lock system - works great

!! Someone earlier said to get it working and enjoy it, it works properly and is nice!

I don't suppose any of you has a good front seat bottom (driver or passenger) that you would sell (one that would fit a 84 300DT)?

Thanks