climate controll blower 25A fuse blows
 

85 300SD keeps blowing 25A fuse when blower is on high setting or in auto when it calls for a high setting. ac and heat works ok on low setting,fuse dont blow on low blower setting. It is a friends car I am trying to help out.
I suspect the motor,but there may be other components. thanx John:confused:

That does sound like the motor is drawing a bit more power than it should.

It's not that difficult to drop the motor out and see if there is anything in the fan, blow out the motor with a compressor, and drop a little bit of ATF on the bushings in the motor.

Here is your answer (you can thank me later):



http://www.peachparts.com/shopforum/diesel-discussion/253697-617-melts-fuse-11-1985-300sd-whats-scoop.html?highlight=fuse

http://www.peachparts.com/shopforum/diesel-discussion/253443-1985-300sd-617-aux-fan-c-thoughts-help-needed.html?highlight=fuse

mine has doing the same thing. I've known for awhile. I don't like the fact that these blowers give out. its annoying. and I'm going to keep buying fuses dag nabit.

Why? Just buy the fix I linked everyone to and get on with life.

This has been an issue with all 80's and early 90's blowers. For the 124's they had a service bulletin to move to an outside the fusebox strip fuse which they mounted on the drivers side strut tower. It was like a silent recall. If you fuse blew they put it in. In 93 on most it was just standard. Its like a 40 dollars kit from MB for 124's, may be a direct fit for others.

it's really simple,they had a 25amp fuse protecting the circuit and the blower motor draws at least 30amps at 95f.the replace kit was a 30amp slower blow fuse.

My '90 has it as does my '87, so I am going to go out on a limb it started around '86. But I have since gotten rid of that 420sel (foolishly) so no idea there.

BUT, my '85 did not have this installed.



Anyway, I posted two links both with the fix. Read them, fix it, life is good.

Come out standard in 93 as far as I know but was a TSB that started getting installed as people started having issue in I dont know when :).