Interior front rotary dash blower : Position 3 dead

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BongoBongo123
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Interior front rotary dash blower : Position 3 dead

Post by BongoBongo123 » Fri Jan 16, 2015 3:55 pm

Has been like this since we had it and the only thing on the whole Bongo that does not
seem to work. Is this serviceable/easy to get out/remove ?

As a guess I imagine you need a new switch in it's entirety as opposed to a squirt of electrical contact cleaner. Just wondering about the process of having a look at it. All positions work except 3.

Happy to just buy one and replace it outright 4 is a bit mental and 2 is not quite enough !

cheers
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BongoBongo123
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Re: Interior front rotary dash blower : Position 3 dead

Post by BongoBongo123 » Fri Jan 16, 2015 5:04 pm

A nice chap at http://www.bongospares.co.uk/ said it may well be a 5 pin resistor that has gone under the bonnet so I am now going to see if I can find that (maybe tomorrow getting a bit dark now)

Ok slightly fiddly but I have the resistor out. If I knew what pins/ohm range to test I could see whether it is broke or not.
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Re: Interior front rotary dash blower : Position 3 dead

Post by Gasy » Fri Jan 16, 2015 5:29 pm

There is info on here somewhere to sort that think they been resold earring it back in or something

Search works better on here with and inbetween search words

Heater and resistor and speed 3
Gas safe heating engineer / plumber if you need any advice just shout.
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Re: Interior front rotary dash blower : Position 3 dead

Post by bigbear » Fri Jan 16, 2015 5:46 pm

I think there is a 'fact sheet' on this.
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BongoBongo123
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Re: Interior front rotary dash blower : Position 3 dead

Post by BongoBongo123 » Fri Jan 16, 2015 5:49 pm

This might help someone else so I will post this up:

Image

I will call the pins as shown in the U shape picture above:

1 _ 5
2 3 4

On a 200 ohm scale I read :

Between 1 and 2 I read = 2 Ohms
Between 1 and 3 I read = 1.6 Ohms
Between 1 and 4 I read = 1.6 Ohms
Between 1 and 5 I read = open circuit

Between 2 and 3 = 3.1 Ohms
Between 2 and 4 = 3.1 Ohms

Pin 5 as I have labelled it has no contact with the rest of the pins.

Have no idea what these pins are ! :lol:
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Re: Interior front rotary dash blower : Position 3 dead

Post by Simon Jones » Fri Jan 16, 2015 6:04 pm

There are some photos here from a repair I did which show what the cause & results are: http://www.igmaynard.co.uk/bongo/forum/ ... =3&t=15511

Factsheet here is also helpful: http://www.igmaynard.co.uk/bongo/member ... sistor.pdf
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Re: Interior front rotary dash blower : Position 3 dead

Post by BongoBongo123 » Fri Jan 16, 2015 6:12 pm

Simon Jones wrote:There are some photos here from a repair I did which show what the cause & results are: http://www.igmaynard.co.uk/bongo/forum/ ... =3&t=15511

Factsheet here is also helpful: http://www.igmaynard.co.uk/bongo/member ... sistor.pdf
Top man Simon, always on the ball =D> and thanks Gasy and Bigbear.

Ok plot thickens. I can see that a solder connection (pin 5) seems to have broken free like a small tinned (soldered) connection has broken free (relative to how the others look)

On closer inspection with a torch I can see a fly has got stuck between the aluminium base and the shielded former (separated by some plastic insulator) that is probably why it overheated and the solder separated.

Photo of said fly forthcoming.
Last edited by BongoBongo123 on Fri Jan 16, 2015 6:35 pm, edited 2 times in total.
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BongoBongo123
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Re: Interior front rotary dash blower : Position 3 dead

Post by BongoBongo123 » Fri Jan 16, 2015 6:17 pm

Here we go you can just see the fly stuck in the resistor module 45 degrees (north east) from the yellow solder flux blob :lol:

Image

I will take a closer look and see if I can solder the connector back on.
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Re: Interior front rotary dash blower : Position 3 dead

Post by BongoBongo123 » Fri Jan 16, 2015 6:32 pm

Ok that went smoothly. I removed the fly and also blew another small insect out first then I have some older lead solder with a lower melting point and put a tiny blob on to "tin" the fixed side of the spring type connector and then pushed down the flexible spring side of the connector with a precision screwdriver and simply pushed the connectors to meet with the tip of the iron an instant bond was made and held in place with the precision screwdriver.

Between Pin 1 an 5 now reads 1.6 Ohms.

I am hoping this does the job.

I will wait till tomorrow cause it is dark now and also for anyone who will warn me "No don't do that it will discharge the flux capacitor!"

Fingers crossed and I might have saved £40.00 or so.
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Re: Interior front rotary dash blower : Position 3 dead

Post by Simon Jones » Fri Jan 16, 2015 9:55 pm

Excellent stuff =D>. It's a nice satisfying repair that one. Plenty of people either would put up with it or just buy a replacement but it's DIYable if you're handy with basic tools.

Not surprised about the insect collection. This is the air con matrix in the space under where the resistor fits and you can see the amount of dead things and bits of accumulated vegetation.

Image

If you unbolt the fan housing you can get the vacuum cleaner nozzle in and give it a good clean.
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Re: Interior front rotary dash blower : Position 3 dead

Post by Northern Bongolow » Fri Jan 16, 2015 11:00 pm

before you plug the resister back in to test it, make sure the heater fan is spinning quite freely, this type of de-soldering is usually because the fan bearing is tight or on its way to seizing, this loads up the resister til it melts.
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Re: Interior front rotary dash blower : Position 3 dead

Post by mikeonb4c » Fri Jan 16, 2015 11:24 pm

Northern Bongolow wrote:before you plug the resister back in to test it, make sure the heater fan is spinning quite freely, this type of de-soldering is usually because the fan bearing is tight or on its way to seizing, this loads up the resister til it melts.
My thoughts also Ady - just couldn't be bothered reading the linked posts to make sure they stressed that. Waste of time soldering unless the underlying cause is addressed, as has been said above.
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Re: Interior front rotary dash blower : Position 3 dead

Post by Simon Jones » Sat Jan 17, 2015 12:07 am

Absolutely true. The photo in the link I posted earlier shows what typically causes the problem. Blocked scuttle drain hole causes water to run into the fan motor so the bearing gets progressively tighter. On this one, the steel shaft had rusted into the bronze bearing and the only reason the fan was still working is that the bearing had worked loose from its mounting. The orange rust marks can clearly be seen here:

Image
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Re: Interior front rotary dash blower : Position 3 dead

Post by BongoBongo123 » Sat Jan 17, 2015 10:58 am

Hmm... ok that's rather annoying I thought it might be the fly that caused the issue consider all other fan speeds work and just one solder tag had broken. I am not even sure where the fan is ?

When I bought the Bongo the very first thing I noticed after finding out about them was this blocked front gutter drain hole and mine was blocked I sorted it pretty much the day after I bought it. So maybe it was not the fly after all.

As I gather from your thread Simon I need to remove that big plastic air guide to access the fan.

Does not the fact that the blower does not work only on position 3 go in favour of the fan working ok ? It seems to blow plenty hard on position 4 and 1 and 2 works ok as well, just 3 was dead and the fly ?

My guess is try it and see if not it position 3 will go again I imagine.

I will await midday cause it is very cold out as I noticed when I popped to the corner shop to get my milk... brrrrrrr
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Re: Interior front rotary dash blower : Position 3 dead

Post by g8dhe » Sat Jan 17, 2015 12:20 pm

The fly will have had absolutely no affect at all! The "fuses" are heat fuses they melt when the strips get hot after heating due to a period of excess current flowing thru the motor, this is normally caused by additional friction within the motor itself, often once the motor gets going it clears the friction itself, its just when it first starts, but it all indicates that the motor is being subjected to extra wear.
You will see the fan and motor housing when you remove the air intake, its much better to give it a clean now before the bearings get worn or more muck sets in around the brushes causing more wear and damage.
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