blower resistor again...

it looks welded on...can I just solder the new one on ? ....

You can short it for a brief test, but it is there to prevent it overheating and potentially a fire.

No you cannot solder it, the heat would melt the solder.

Some sort of mechanical connection is the only way - tiny nut and bolts, crimps, or point contact welding.

One of these?

If you solder it, use the 'heat shunt' method with pliers- like we used with old fashioned transistors.

This one is more clear:

I take it you have seen the videos/reports of *certain* cars going up in flames because of overheating fan resistor packs? Watchdog did a feature about it ISTR... ;)

Just a helpful note, check the cabin filter isn't clogged, for obvious reasons.

If you've never changed the Duster's cabin filter since you got it, I'm not surprised it overheated. It must stink.

Hold the wire, between the body and joint, with pliers while soldering.

As Harry mentioned, wrap the wire first and 'nip it' up. The solder is really just to stop it shaking.

Unless it overheats, the solder shouldn't really melt in normal use.

If, as it sounds, you've not changed the filter, it could be it has overheated. Filters should be changed every year at least. They aren't expensive- I pay between £7 and £20 or so, depending on the car. Usually a 5 min job.

Even worse, the all kinds of 'cr*p', including leaves, can end up in the heater. Often, there is space for one in the basic model - they just don't put the filter(s) in. Worth finding out and inserting. Helps if someone has Hay Fever as well.

If you say so.

Of course, there is nothing stopping leaves, seeds etc, getting into the heater. But you save a few pounds a year.

After all, something caused your current problem.

Generally only fitted in cars with air-con. If dust and pollen enter the system whilst the condenser is chilling, they?ll stick to the damp condenser. If you don?t have air-con, you don?t *need* a filter.

Tim

That?s not going to stop if falling off when it gets hot enough to melt the solder but not to blow the thermal fuse in use.

Not usually feasible with thermal fuses.

But will melt before the thermal fuse blows.

Is the motor a brushed on, and is it worn or damaged internally? The extra current spikes from a faulty motor can easily blow fuses., what else protects the thing if the motor seizes and shorts out the supply, do the resistors catch fire? Brian

One must ask ones self, why is this fuse here. I think you might just find the flaw in your cunning plan? Brian

On the one I fixed by replacing the thermal fuse I found the motor shaft showing some signs of rust so out with the dip stick and one drop of engine oil was run down the shaft to the bearing.

When I replaced the thermal fuse I cut the wires on the old fuse close to the body of the fuse. This left enough wire to fold over to make a mechanical connection to the new fuse leads before soldering.

Depends on the car. Ford used to save money by not installing a pollen/cabin filter on their lower range models. On my previous car the filter was fitted to the cabin air intake at the bottom of the windscreen

tin/lead solder will melt at 370C The thermal fuse will be 150C to 200C lower.

In normal use fuse will blow long before the solder melts. If the solder melts in normal use you will have a greater problem than a blower motor fault!

I've used a high power soldering iron to solder to the leads of thermal fuses without the problem of the fuse blowing. As other have said you can heat shunt the body of the fuse to prevent the body of it getting too hot but in my experience a 10 second application of a soldering iron to the fuse lead doesn't result in the body of the fuse getting too hot. There may be a problem of using a low power soldering iron that has to be left on the solder joint far too long. Clean up old wires and tin with fresh solder before making the joint.

They are normally thermal fuses, more thermal cut outs really, that don the reset. They don?t tend to respond to short term spikes etc. They are more for if the motor is jammed - leaves etc- or there isn?t enough air flow to keep things safe, etc.

Resistors tend to be made from non-combustible materials but they can ?cook? and get hot enough to cause other things to burn, melt etc.

There is another conventional fuse in circuit.

The thermal fuse is in close proximity to the resistors and if they get too hot the thermal fuse blows stopping the resistors getting any hotter by removing th voltage across them

Wirewound resistor on a ceramic core and with a ceramic coating. In the past I've seen this type running red like a electric bar fire before going open circuit. In this case the thermal fuse would blow long before the resistors reached a temperature where they could cause a problem.