I am wondering......
 

Has anything like this ever happened on a W126, (concerning the blower motor), or are they setup different that the E-Class?

I know there has been issues with "leaf buildup" under the fuse box of a W126, which I am about to start another thread about.

AS Steve stated, problem with previous repair.

Retaining screw too long OR using a GLOW system fuse rated at 50A or higher!

Have seen the same problems with the W126 chassis from 1986! CHECK the fuse rating & make sure that ONLY a 30A fuse is used.

Stevebfl
MBdoc

Stop beating your heads against the wall.:D

I had my fuse burn out, and noticed the following
 

I believe that this is a poor design more than anything else. Fuses are not only rated by their amps, but whether they are 'slow burn' or 'fast burn'. This is really a fusable link, and designed for 'slow burn'. It really shouldn't be! If there is excessive current draw on the blower motor, the fuse should pop right away.

My fuse burned without starting a fire, but the plastic housing was melted due to the heated slag of the fuse material. Also, upon close inspection of the material, the fuse link had obviously heated to the point of a metal fire and was severly oxidized and liquified.

I'm going to replace mine with a circuit breaker.

fires + cars scare me. I have a 93 190E is this somthing i should investigate...I mean so far I havent seen anything to indicate a problem of this level. We drove it 10hrs (VA to OH) with the A/C on and the only thing we experienced was a "white smoke" that came out of the vents for a little while...it had no odor to it once so ever. It only lasted for maybe 15 minutes.

glad to see no one got hurt.

Don't really seem like its an issue on the 190E... most cases seem to come from the "E-Class" chassis.

I do not think that white "smoke" is cause for concern, as far as electrical goes. I do not recall what make of car it was, but my aunt had a car that did this once and the mechanics told her it was condensation. It only did it occasionally. I think it is more like moisture/condensation. Just make sure it does not smell electrical.

If fire concerns you , I suggest you do what we do.... carry an auto fire extinguisher. We carry them for safety in ALL of our cars. Heck, in one car, I have two of them. The extinguisher in my dads car saved a car (not ours) that was on the highway from a potential major fire. He "thought fast" and disconnected the battery, then sprayed it with the extinguisher. Luckily only minor damage to that car. What had happened was that someone had miswired a generator (was a 50s car) and it had severely overheated and set the wiring harness from the generator ablaze. :eek:

cdplayer
 

I just bought a 1984 126 and drove it 700 miles home with no problem. But one Sat. while checking the AC operation under the hood a small fire erupted just under the brake master cylinder. As it turned out this car had been parked under trees. And a bunch of leaves had collected in a space behind the engine and in front of the firewall. Well, over time these leaves became compacted and eventually collected near the blower resister. The resister is a metal box like a big piece of swiss cheese with four springs inside it. It was the springs that glowed red hot that ignited the leaves. Lucky for me the car was idling in my drive way when the heat generated by the resistor finally caught the leaves on fire. No damage though. I replaced the resistor and the blower motor too. I used a strong shop vac to remove the debris. Now all is well.
Just thought I would bring this up. And for everyone to take a closer look at the small space under their brake master cylinders.

I am going to have to clean out under that on my 85'. I have tried to use my hands, but that is impossible. Very poor design if you ask me.

check this out.... :eek: .....any relation to this thread ?

This is very common problem....as per the above explaination.
Fuse material corrodes in contact with screws....this causes high resistence...couple this with high amp draw from a failing blower fan and heat enough to allow holder to melt . ....sometimes this heat is enough to ignite the plastic.

In every service on vehicles so equipped, I have checked blower amp draw to prevent loom damage .

Fuse would be better if suspended....then fuse strip should blow.
Have often found 80 amp strips used in this location bent up as they are longer than the holder.






.

I have had the same issue with meltdown a while ago and about to do the repairs now. My problem is that after the fuse housing burned, I lost the +12 at the fuse leg, which goes inside the car into a bundle (to the ignition switch?). Has anyone experienced the severage of the +12 connection?

I have been driving the car for six months now without wiper or AC.

For repair of the +12 leg. What would you recommend?
BTW, mine has the cabin filter which may have caused the whole issue as Steve mentioned above. So, I would say replacement of cabin filter is a good maintenance item to keep.

+12V line repair question
 

I have had the same issue with meltdown a while ago and about to do the repairs now. My problem is that after the fuse housing burned, I lost the +12 at the fuse leg, which goes inside the car into a bundle (to the ignition switch?). Has anyone experienced the severage of the +12 connection?

I have been driving the car for six months now without wiper or AC.

For repair of the +12 leg. What would you recommend?
BTW, mine has the cabin filter which may have caused the whole issue as Steve mentioned above. So, I would say replacement of cabin filter is a good maintenance item to keep.

+12V Repair Q
 

OK...

Let me rephrase, to make the answer simpler.

Is there a +12 (past ignition switch) terminal under the hood that I can access and use for my power on the blower?

If not, I know how to get +12 that's not connected to the ignition switch where power would be on constantly. Is there harm in doing so?

Thanks for your help. I am not in a big rush to finish, but it would be nice to put things back together soon...

Yasser

sorry to butt in but have you considered that the fuse that fits in the little holder looks the same whether it's a 30 amp,50amp or 80amp.i have read the whole thread and my guess is that the original blown fuse was replaced with probably an 80amp[glow plug] fuse and a worn blower motor drawing too many amps[tight bearings]caused the little fuse holder to heat up and because of it's placement in the 124 body as it melted one of the screws dropped and touched the body and caused more heat and voila! if the correct fuse had been in there it would have popped long before enough heat to cause the problem.someone who didn't know any better went to box of spare fuses,saw what looked like identical fuse and put it in and the blower worked not realising that it was a fire waiting to happen.suggest that you all go to your fuse holders and check the amperage on the fuse.of course the next time that someone fits a wrong fuse instead of replacing the blower motor[too many dollars and what harm will a bigger fuse do anyway] will not be the first time.

I am having this problem right now actually. My blower motor was working fine until one day it stopped and I thought I blew a fuse. Looked in the fuse box and the fuse was melted, but the copper was not broken. At first I attributed it to an older fuse and oxidation, so I went out and bought some new ones and rewired the box to move the blower motor fuse to an unused slot. Worked for about 3 hours and the same thing happened. I thought it must be oxidation on the connectors for the wire leading to the blower motor, so I clipped the ends off and wired in an after market inline fuse outside of the box. I started up the car, turned on the AC and monitored the fuse temp for about 5 min, at which point it got too hot to touch. I have a new blower motor that I am going to try to put in tonight so we'll see if that fixes the problem, but I'm a little concerned that a 25 amp fuse will actually MELT before it blows out (I believe they are 25 amps, but I could be mistaken).

Oh, the car is an 86 300E that I've had for a little over 8 years.