86 300SDL- newbie repair questions
#1
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Hello, not only is this my first post here, but also my 1st MB. It bought it with fairly extensive repair receipts and it is in pretty good condition. The body is very straight with a little rust on the front L&R fender near the corner lamps. Runs and idles awesome.
The odometer which recently stopped working is showing 468,000. I have ordered a service manual, but have a few questions someone may be able to help me out with in the meantime.
1. Fuse #15 blows every time I replace it. How should I start to diagnose where the short is?
2. brake lights (including 3rd aren't working)
3. Speedo works, odometer doesn't. Is this just a cable?
4. shifter gears don't illuminate. this may be part of the things covered by fuse 15?
-Tranny shifts fine and doesn't slip up hills or under fairly hard acceleration, however does leak a fair amount after driving 30 or more miles. Is that a sign she is about to go or could it be a seal?
Aside from changing the oil and filter, what else do you recommend i do right away (aside from the tranny leak which I am going to have looked at)
Thanks
The odometer which recently stopped working is showing 468,000. I have ordered a service manual, but have a few questions someone may be able to help me out with in the meantime.
1. Fuse #15 blows every time I replace it. How should I start to diagnose where the short is?
2. brake lights (including 3rd aren't working)
3. Speedo works, odometer doesn't. Is this just a cable?
4. shifter gears don't illuminate. this may be part of the things covered by fuse 15?
-Tranny shifts fine and doesn't slip up hills or under fairly hard acceleration, however does leak a fair amount after driving 30 or more miles. Is that a sign she is about to go or could it be a seal?
Aside from changing the oil and filter, what else do you recommend i do right away (aside from the tranny leak which I am going to have looked at)
Thanks
#2
![Default](/forum/images/icons/icon1.gif)
congrats on 486,000 miles.
The tranny, if working properly should not be opened. It sounds like just a seal as those seals do go out after time. Some are paper like substance like the tranny seal or rubber like some pan seals. most are easy to replace with worst case scenario is removal of tranny which is not hard but can be pain to line up and put back on just due to the sheer weight of it.
There is a cable and a few plugs on the back of the speedo set. I think the cable is suppose to control the speedo and rpm guage (tach). Odometer I dont remeber of top of mind but I know after a few hundred thousand miles those type of odo fails when the internal little gears wear out or become broken. Most people dotn bother with repairing it as those pieces can be tiny but if you understand gears on a small level, such as toys, you can do it but I have no idea where to get the little gears from.
And when the fuse blows, doesit goes after replacement of fuse, when yu step on brake light? Or as soon as you turn on car. But first and foremonst check to see if fuse is proper voltage. To tell you what fuse does what, I'll have to find my fuse chart which I misplaced a week ago.
brak lights, check brake light switch.
The tranny, if working properly should not be opened. It sounds like just a seal as those seals do go out after time. Some are paper like substance like the tranny seal or rubber like some pan seals. most are easy to replace with worst case scenario is removal of tranny which is not hard but can be pain to line up and put back on just due to the sheer weight of it.
There is a cable and a few plugs on the back of the speedo set. I think the cable is suppose to control the speedo and rpm guage (tach). Odometer I dont remeber of top of mind but I know after a few hundred thousand miles those type of odo fails when the internal little gears wear out or become broken. Most people dotn bother with repairing it as those pieces can be tiny but if you understand gears on a small level, such as toys, you can do it but I have no idea where to get the little gears from.
And when the fuse blows, doesit goes after replacement of fuse, when yu step on brake light? Or as soon as you turn on car. But first and foremonst check to see if fuse is proper voltage. To tell you what fuse does what, I'll have to find my fuse chart which I misplaced a week ago.
brak lights, check brake light switch.
#3
![Default](/forum/images/icons/icon1.gif)
congrats on 486,000 miles.
The tranny, if working properly should not be opened. It sounds like just a seal as those seals do go out after time. Some are paper like substance like the tranny seal or rubber like some pan seals. most are easy to replace with worst case scenario is removal of tranny which is not hard but can be pain to line up and put back on just due to the sheer weight of it.
There is a cable and a few plugs on the back of the speedo set. I think the cable is suppose to control the speedo and rpm guage (tach). Odometer I dont remeber of top of mind but I know after a few hundred thousand miles those type of odo fails when the internal little gears wear out or become broken. Most people dotn bother with repairing it as those pieces can be tiny but if you understand gears on a small level, such as toys, you can do it but I have no idea where to get the little gears from.
And when the fuse blows, doesit goes after replacement of fuse, when yu step on brake light? Or as soon as you turn on car. But first and foremonst check to see if fuse is proper voltage. To tell you what fuse does what, I'll have to find my fuse chart which I misplaced a week ago.
brak lights, check brake light switch.
The tranny, if working properly should not be opened. It sounds like just a seal as those seals do go out after time. Some are paper like substance like the tranny seal or rubber like some pan seals. most are easy to replace with worst case scenario is removal of tranny which is not hard but can be pain to line up and put back on just due to the sheer weight of it.
There is a cable and a few plugs on the back of the speedo set. I think the cable is suppose to control the speedo and rpm guage (tach). Odometer I dont remeber of top of mind but I know after a few hundred thousand miles those type of odo fails when the internal little gears wear out or become broken. Most people dotn bother with repairing it as those pieces can be tiny but if you understand gears on a small level, such as toys, you can do it but I have no idea where to get the little gears from.
And when the fuse blows, doesit goes after replacement of fuse, when yu step on brake light? Or as soon as you turn on car. But first and foremonst check to see if fuse is proper voltage. To tell you what fuse does what, I'll have to find my fuse chart which I misplaced a week ago.
brak lights, check brake light switch.
I do have the fuse chart, so thank you just the same.
I did get the brake light switch, have you ever done one before and will i have to wait to get my manual 1st?
#4
![Default](/forum/images/icons/icon1.gif)
I never repaired did the brake light switch personally but it's located t the pedal and it looks like a small push button switch, with two plugs connected to it iirc. It's at the top of the pedal and you can just about see it if you stand on your head and look under the dash where the pedals go. From the looks of it, a screw driver should do and removing the plastic peices from under the steering wheel gives more room and access. The switch is treaed into the brake pedal pedastal and retained with lock nut. Now the venting under the dash in that section might block the view and will have to be moved or removed to actually get to it.
It's a simple job from the looks of it as you'll be spending the most time getting to it and maybe putting the new one in. It'sa pretty tight spot but one you get a hold of it, it's down hill from there.
It's a simple job from the looks of it as you'll be spending the most time getting to it and maybe putting the new one in. It'sa pretty tight spot but one you get a hold of it, it's down hill from there.
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