Door Lock Mercury Switch

[noiva]

I have a deadbolt that sounds a buzzer if I turn on the MoHo engine without locking it. At least, it used to sound a buzzer. I disassembled the locking lever and discovered the two wires went to what looks like a mercury switch mounted inside the lever. By removing the switch I can move it around and cause the buzzer to go off intermittently, but not consistently. I'm sure the switch is bad. Does anyone have experience with replacing these switches? It's not really crucial, of course, but I have tried to drive off once or twice and been reminded to deadbolt the door by that buzzer. I would like to get that working again.

[Robfike]

Tim,
On our 345, the buzzer works just part of the time as well. I think the problem with mine is the buzzer. When it does not buzz, if I tap on it it will start. It is just wire tied to a bundle of wires behind the dash in the area of the vacuum guage.
I also need a mercury switch though for my "Step" warning light.
Good luck, Rob

[Chaplain Kent]

I changed mine to a light on the dash. Now when the door is not dead bolted the light flashes at me. This is much better than a buzzer.

[noiva]

Originally Posted by Robfike

Tim,
On our 345, the buzzer works just part of the time as well. I think the problem with mine is the buzzer. When it does not buzz, if I tap on it it will start. It is just wire tied to a bundle of wires behind the dash in the area of the vacuum guage.
I also need a mercury switch though for my "Step" warning light.
Good luck, Rob

Rob, I guess it just depends on which component decides to quit first. Mine is definitely the switch since I can play with it at the door and cause the buzzer to sound - just not when it's supposed to. By the way, the manual says my coach has a light on the dash - no mention of a buzzer .

Apparently I don't even have a "Step" warning light. My step is manufactured by a company called Kwikee, which I'm guessing is not the same manufacturer of yours? There is no mention of a warning light in the manual (no surprise there ), but the wiring diagrams don't show one either.

Thanks,

[noiva]

Originally Posted by Chaplain Kent

I changed mine to a light on the dash. Now when the door is not dead bolted the light flashes at me. This is much better than a buzzer.

Kent,

How did you activate the handle to send a signal to your dash light (which, by the way, is what the manual says I have - but I don't )? Did you use the wires from the original switch in the locking handle or do it some other way?

Thanks,

[noiva]

OK, after a thorough disassembly of the deadbolt handle I discovered, under very close inspection, that the problem is one of the two wires going into the mercury switch is just about broken off of the switch. I'm going to attempt to solder the wire back on the switch tomorrow, but it's one of those molded assemblies where the wire is actually molded into the tubular switch housing. Going to be tough to get a good clean solder joint w/o melting the casing of the switch. Anyone know if the switches are available if I fry this one?

[Chuckles]

I general terms the mercury switch is very reliable and is normally the last thing to look at, apart from broken wires that is....

Mercury switches are often used in steam boilers (Controlled Flame Boilers) and some Drayton level switches to monitor water levels . These are glass ones and can stand all sorts of abuse.

I will, when I get a minute, have a look at my switch and see what size it is. Its possible that I have an odd one in stock, but there may be a problem sending mercury to the USA with all this hype on liquids.

Hope this helps

[Chaplain Kent]

Originally Posted by noiva

Kent,

How did you activate the handle to send a signal to your dash light (which, by the way, is what the manual says I have - but I don't )? Did you use the wires from the original switch in the locking handle or do it some other way?

Thanks,

I used all the existing wires and the rocking switch which was there inside the handle. If I remember correctly it was a mechanical and not a mercury switch.

[noiva]

Chuck and Chaplain,

Thanks to you both. After I attempt this wire solder on the switch connection today I'll know whether I need to do further work. Hopefully, I can get the solder to hold that close to the switch - which is basically a round cylinder (solid and sealed completely on the outside). If I can get it to take a dab of solder, then solder the wire back in, I should be OK.

Chuck, I'll post how this comes out, so we can see if another switch is needed.

Chaplain, my buzzer (actually more of a beeper) seems to work fine, but I really appreciate the light on the dash idea. Unfortunately, I can't get either (Beeper or light) to work correctly without the switch on the deadbolt lever.

Thanks to both for being so willing to help out.

Best,

[noiva]

At least for now, the problem is solved. I was able to solder the wire back to the mercury switch, and all is working now. Can't say how long this will last, but I suspect the constant movement of the wires as the switch goes vertical and then horizontal is going to cause this to happen again.

Thanks for the help and offers.

[lewster]

Tim,

Kwikee Manuf. makes electric steps that are controlled by a magnetic reed switch in the door. If you need a new mercury switch and can't find one, you might ne able to adapt a reed switch to serve the same purpose. I usually have a couple lying around. Let me know if you need one.

[noiva]

Originally Posted by lewster

Tim,

Kwikee Manuf. makes electric steps that are controlled by a magnetic reed switch in the door. If you need a new mercury switch and can't find one, you might ne able to adapt a reed switch to serve the same purpose. I usually have a couple lying around. Let me know if you need one.

Lew,

Thanks. If I have any further problems with the door lock warning switch, I'll contact you. My steps are made by Kwikee, so I can at least identify those parts . So far, the steps actually haven't given me any problems - probably a bad sign .

Best,

[Punch]

I couldn't help sharing this. If you are Canadian, you are accustomed to this happening, but sometimes the scale of it can still surprise you. I was looking for a tilt mercury switch for the dead bolt, and found this on Amazon.com, the US site



That's pretty cheap... I wonder if it is available on the Canadian Amazon site? Why yes it is, and it is the same Parts Express item, but, Oh my!!!!




Plus shipping is an additional $9.95.

So much for NAFTA!

[PeterH-350LE]

Originally Posted by Punch

I couldn't help sharing this. If you are Canadian, you are accustomed to this happening, but sometimes the scale of it can still surprise you. I was looking for a tilt mercury switch for the dead bolt, and found this on Amazon.com, the US site

Attachment 248643

That's pretty cheap... I wonder if it is available on the Canadian Amazon site? Why yes it is, and it is the same Parts Express item, but, Oh my!!!!

Attachment 248644


Plus shipping is an additional $9.95.

So much for NAFTA!

unbelievable.......I would consider that to be a rip-off