'82 300D Noob seeks wisdom... - PeachParts Mercedes-Benz Forum

Biofarmer93 · #1 03-08-2011, 09:19 PM

Greetings to the forum. I was told by a friend of mine that this is THE place for info and guidance on older MB's... Needless to say that after reading several dozen posts- I can see he was right. Hopefully someone will be able to share some ideas with me about why my blinkers worked just fine last night, but don't work at all now. I checked the fuse and it is intact. My running lights and my brake lights still work. Is there a secondary fuse/relay/breaker or a known failure point somewhere that I should look at? Any help at all would be greatly appreciated. Thanks!

vstech · #2 03-08-2011, 09:30 PM

and WELCOME to the best Mercedes forum (if not the best car forum of any kind!) glad you decided to post!
turn on your emergency flasher then turn it back off...
common failure on these cars.
now that I think on it, yours may not be solved by this. you could need a replacement flasher module. it's under the radio in front of the shifter I think.
try the flasher button first though.

Biofarmer93 · #3 03-08-2011, 10:08 PM

BINGO! You nailed it in one try. Thank you! Obviously that was just too easy... OK then, again- all fuses are intact, but there are no instrument lights at all (and haven't been since I bought it) and my wife and daughter just shake their heads at me and say things like "Dad, that's SO ghetto" when I use the little LED light on my key ring to check my speed at night. Lesser men might not tolerate such derision, but I love my diesels. I also have an '89 F350 NA 7.3 idi that has its own personality issues. Being much larger, it has been easier for me to work on (sausage fingers).

vstech · #4 03-08-2011, 10:43 PM

yup. the lights are controlled through the dimmer adjust lever.
the button for resetting the trip odo (is your's working? easy fix on dieselgiant.com with some changes to his method on here...) anyway, turn the knob back and forth and sometimes you can get the lights back on... easiest to pull the cluster out,and solder a jumper across the dimmer!

vstech · #5 03-08-2011, 10:45 PM

and look your fuses over carefully!! if anyone put in, plastic with aluminum element fuses from autozoo or wallyworld, you'll be chasing electrical issues forever. pull every aluminum fuse now and change them for OE copper and tin plated copper ceramic body fuses ASAP!

Biofarmer93 · #6 03-08-2011, 11:39 PM

HA! It figures... Every fuse in there is plastic and aluminum. I have already cleaned oxidation powder from several of them and put them back in with a dab of NOALOX on each end. I must admit to zero experience with fuses that look like these- when I first saw them I didn't even recognize them AS fuses, it took a couple seconds to understand what I was looking at.
The trip meter and odometer are both out of commission, but I will attempt to wiggle, jiggle and twist to see if something will happen- thank you for the tip, as it would never have occurred to me that the panel dimmer would be tied into the trip meter knob!

While we are on topics electrical, is there a standard go-to alternator upgrade for these cars? I will be needing some extra amperage in the near future and would like to do the most trouble free swap I can.

charmalu · #7 03-09-2011, 12:03 AM

There is a 115amp Bosh alternator that is used in the Saabs that will fit the 300D. it is a little larger in size, but will fit in.

Do a search on AL-129-X, that is the alt part number.

Charlie

Paulc66t · #8 03-09-2011, 08:10 AM

I believe most of these come with a 50 amp alternator. You can get a 65 that is a drop in replacement. Other than that the Bosch 115 upgrade makes sense - though you have to replace the connector.

charmalu · #9 03-09-2011, 09:33 AM

when I instaled mine, I removed the alternator harness,using it as a template, made a totally new one. ran larger wire, soldered on new connectors. I covered the wire in shrink on tubing so it looks stock w/o the gaudy red, blue, green etc...wires showing. ran the harness to the connector box next to the battery, then ran a larger wire to the battery.

when you are all done, it looks like it came from the factory.

I believe the 300D turbo`s use a 65amp alternator.

Charlie

Yak · #10 03-09-2011, 09:43 PM

Quote:

Originally Posted by Biofarmer93

The trip meter and odometer are both out of commission, but I will attempt to wiggle, jiggle and twist to see if something will happen- thank you for the tip, as it would never have occurred to me that the panel dimmer would be tied into the trip meter knob!

.

Re: panel dimmer. Do a search for "rheostat" and you'll find pics, hints, etc.

charmalu · #11 03-09-2011, 11:49 PM

Here is a good Al-129-X thread. It`s a long one.

http://www.peachparts.com/shopforum/showthread.php?t=93569

Charlie

vstech · #12 03-09-2011, 10:44 AM

the 80 amp alts from similar year gasser MB's is a direct drop in replacement too. I've used plenty of them. no wiring changes required...

TnBob · #13 03-09-2011, 07:44 PM

Cleaning connections with a brass wire brush is good too. Anything left will just add to the connection. Great for fuse connections.

Biofarmer93 · #14 03-09-2011, 09:11 PM

Gentlemen,
Thank you for all the suggestions. I'll be swapping in the Bosch AL129X that Charlie mentioned. Upgrading wiring on old diesels seems to have become a second career for me in the last two years. Do you know that I have every size of heat shrink offered, color coded electrical tape, 4 different kinds of solder, 3 kinds of flux and even some .07" copper sheet for making custom connectors? The cashiers at Home Depot all know me by my first name and the manager at the local Ace Hardware will drop whatever he's doing just to walk around with me and see what I'm getting today- I think after so many obscure requests he just had to see what this person looked like... Thanks for your help guys!