removal of exhaust fan blade.

[ivanhoe]

I've been trying to remove my exhaust fan from my Harman Accentra stove but having no luck yet. I've sprayed premium penetrating oil quite a few times and also broken a allen key. Any tricks on doing so before i get frustrated and break something else. I could heat it with a torch but that could be hard on the exhaust motor!
Thx,

 

[MountainSean]

Just keep doing what you are doing. It really isn't unusual for those things to get on their tight enough to not get em off without breaking.

 

[wil lanfear]

It sounds like you haven't been able to loosen the setscrew on the fan. If this is the case, using a flashlight, check to see if the setscrew has a crack where the allen wrench is inserted. If it's cracked, when you try to loosen it, what you are doing is expanding the setscrew thread against the internal thread of the fan which will make it impossible to loosen.I'm quite sure you will end up drilling the setscrew out if it's cracked.

 

[mepellet]

When/if you get the setscrew out, put some anti-seize on it when putting it back in.

 

[ivanhoe]

When/if you get the setscrew out, put some anti-seize on it when putting it back in.

Oh yeah baby, anti-seize the crap out of it! Hopefully there's no crack in the set screw. Drilling out a set screw might be next to impossible 'cause of the harden steel.

 

[peakbagger]

Pick up left handed cobalt steel drill bit. The cobalt steel will cut most hardened screws and the counterclockwise twist tends to looses the screw up. Automotive stores may carry then or there is always on line

 

[ivanhoe]

I will put the stove on a drill press and slowly drill out the set screw, that should do it ! Now if it should be that easy to get a drill and a tiny drill bit inside the stove and apply evenly pressure would be the last resort. Oh, the confine places to stick our heads into.....wait a minute, we have been doing so when we do a thoroughly cleaning on OUR stoves.

 

[Delta-T]

why remove the impeller? I clean around the whole thing with a paintbrush. If it comes to it, those impellar set are like $10-15...with new set screw!

 

[mepellet]

why remove the impeller? I clean around the whole thing with a paintbrush. If it comes to it, those impellar set are like $10-15...with new set screw!

Can clean it better with the impeller removed. Yea 10-15 but if you have to cut the motor shaft because you can't get the impeller off it's a bit more.

 

[Don2222]

Hello
There certainly is a trick! When a set screw gets frozen from oxidation the portion that oxidizes is the surface between the screw and the threads. Even though it may not look different. Therefore if you use a wire brush and brush all around the edge of the set screw as hard as you can then spray with PB blaster you should be able to loosen the screw by hand with an Allen wrench. I use a wire wheel on my drill/driver to do the hard brushing! It work on a 12 y/o P61 so it should work on most stoves barring an extreme rusted out case!

I also use VHT Flame Proof very high temp flat black on both sides of the combustion retainer assembly that goes over the impellers! That keeps it from rusting!

 

[ivanhoe]

I want to make sure it comes off easily when the motor fails. Last winter the motor started to show it's dark side !

 

[Don2222]

Here are a few pics. Hope this helps

You can see my drill/driver wire wheel and wire brush, the emery cloth, Acetone and the dry moly I use to make it clean and really smooth!

You can either buy a nice new combustion blower impeller or if yours cleans up well, just dry moly it and it will be smooth running especially with some Tuff-Oil Lubit-8 on the shaft!

 

[ivanhoe]

Here i was looking for PC Blaster with no results! It's called PB Blaster. Further looking into this penetrant, I've found others like KROIL, aviation mouse milk (hard to find but the best)...., Tuff oil for shaft lubrication like anti-seize?

 

[imacman]

Here i was looking for PC Blaster with no results! It's called PB Blaster. Further looking into this penetrant, I've found others like KROIL, aviation milk something(hard to find but the best)...., Tuff oil for shaft lubrication like anti-seize?

PB Blaster is probably the best all-around "rust buster". Spray on and let sit overnight. Also, try tightening the allen screw slightly first before trying to unloosen....it helps break any corrsion or rust that might be holding the screw.

As for lubrication of the screw, the Tuff Oil is good, but I'd use a little dab of Hi temp anti seize.