12v conversion but indicators not quite right

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topnotch
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12v conversion but indicators not quite right

Post by topnotch » 23rd May 2010 - 9:52pm

hi - i`ve just bought a 65 square back which has had a 12v conversion. It all seems ok apart from the indicators which instead of a nice switching on and off don`t work quite right. They seem to `flick` on and off at about twice the speed they should and when they light up, its a veyr short flick on and off and not too bright.

All of them do exactly the same. I` not sure if the flasher was changed or not ( or if this has to be even done).

Also, the windscreen wipers are very quick - i guess the best thing here may be to fit some sort of voltage dropper before they burn out?

cheers, mike
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miketyp3
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Re: 12v conversion but indicators not quite right

Post by miketyp3 » 25th May 2010 - 6:22pm

Yes it does sound like the relay and the wiper motor are still 6v.
You can substitute a later 12v relay, just take notice of the connections on the old relay (31, 49a etc) and apply them to the later one. I think there may be an extra connection on the 6v one, but without looking at one I can't remember what it's for. If it's a problem post back and i'll look it up.

Not sure if a dropper would work on the wipers, but a 6v light bulb wired in series is an old school fix ;o)

Mike
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topnotch
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Re: 12v conversion but indicators not quite right

Post by topnotch » 26th May 2010 - 8:32am

thanks - `ive ordered a 3 pin beetle flasher which should do the trick. I`ve also ordered a voltage reducer thing which has a heat sink on it to soak up the extra voltage and a knob on it so i can adjust the speed of them - hope that works - it wasn`t cheap!
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topnotch
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Re: 12v conversion but indicators not quite right

Post by topnotch » 28th May 2010 - 1:50pm

thanks mike - i managed to fit a 12v beetle relay and all is well with indicators now.

i ordered an expensive csp 12v to 6v wiper voltage reducer. I wired it all in, checked the output voltage which was about 7 v or so and not a dicky bird from the wipers! Connected them back to proper 12v supply and they worjked no probs again so i`m not sure if the wiper motor has been changed or not. To be perfectly honest, it looks like its never been removed from the car and the wipers do go quicker than i`d expect them too.

I`ve sent the csp converter back now but how does the 6v bulb fix work as i may try this to see what happens? Do you wire it in between the live feed from the fuse box and the switch? How does it work as i`d expect the 6v bulb to blow as soon as you swithc the ignition on?

Its forecasting rain in the next couple of days so i may have to use them soon!!!
Cheers, Mike
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Re: 12v conversion but indicators not quite right

Post by topnotch » 28th May 2010 - 2:25pm

just done research on the internet and i understand what you mean now - its taken me back to gcse electronics! With it in series with the wiper motor, the voltage drop would be 6v across both components - makes perfect sense. Will stop by maplin on my way home tonight :)
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Re: 12v conversion but indicators not quite right

Post by miketyp3 » 28th May 2010 - 9:43pm

I don't know how the CSP unit works so can't really comment on why it didn't work.
If you can get a number off the wiper motor, a few of us on here have parts books so someone should be able to say what voltage its expecting...

It shouldn't matter where the bulb is in the circuit, as it will do the same job whatever but,
use a low wattage one such as a side light bulb (or lower if you can get one) as it will add to the current drawn.

Mike
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Editor
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Re: 12v conversion but indicators not quite right

Post by Editor » 1st June 2010 - 12:52am

I think if it was as easy, we wouldn't have seen electronic solutions. If you need, say, 4 amps for the wiper motor to make it work (that's at a guess - it could be more on a 6V motor), you would need that to flow through the bulb as well. With 6V across it and 4 amps through, that means maybe a flasher bulb would do. A 12V bulb at 6V takes proportionately a larger current as it isn't as hot and so the resistance is lower and the voltage dropped across it will be greater.

A side-light 4W 12V bulb would be max brightness at 1/3 Amp. The wipers wouldn't run at that.

I don't know if the surge when switched on or off would cause a problem. It might go fine until it tries a dry or frosty screen and has to work harder.

Bulbs do regulate the current to some extent, but running brighter (hotter).

It won't cost much to try.
Dave.

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topnotch
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Re: 12v conversion but indicators not quite right

Post by topnotch » 1st June 2010 - 7:09pm

had a look at the wiper motor - the number was printed not stamped so its pretty difficult to make out - it is possibly - 312-5**-*** - sorry - thats all i could get!
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Re: 12v conversion but indicators not quite right

Post by aircoolsteve » 1st June 2010 - 8:14pm

wipe a bit of spit over the number and put it under a light. wriggle it about in the light. it works sometimes!
steve

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Re: 12v conversion but indicators not quite right

Post by Editor » 1st June 2010 - 11:19pm

312 is right hand drive Type 3. The 5 is actually a 9 for electrical and 55 for wiper motor. The rest is what matters! 111 for 6V and 113 for 12V plus a letter usually, which tells us what it went on.
Dave.

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Re: 12v conversion but indicators not quite right

Post by topnotch » 2nd June 2010 - 7:48am

cheers! its always the bit you need! i`ll see if i can decipher betweeen 111 and 113 but i`ll be lucky i think!
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Re: 12v conversion but indicators not quite right

Post by topnotch » 6th June 2010 - 9:49am

had a look at this again yesterday. the stamp on the motor is very hard to see, but if anything i`d the last figure looks `slightly` more like a 1 then a 3!

i wired in a 6v indicator bulb in series and then also tried a small dash light too. Both bulbs lit up brightly when the wipers were switched on but absolutely nothing from the wipers. Connected back up on their own and they worked perfecly but admittedly pretty quick!

I guess the motor was probably swapped for a 12v one now having tried both bulbs and the voltage dropper thing for coolair.

They still do go alot quicker than most 12v cars i`ve had! The only other thig i thought was that the 6v wipers rheostat switch is still being used. Its set to the `slowest` :lol: setting at the moment. If adjust it up to a faster setting, the wipers look like they`re about to take off into next doors garden!!

Would the 6v rheostat switch make a diifference?

cheers
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Re: 12v conversion but indicators not quite right

Post by Editor » 6th June 2010 - 1:23pm

I assumed a wiper motor must take around 4amps current, but it may be more for a 6V one. I've a feeling our 6V Variant had a 16A fuse for the wiper, and looking at the '63 Notch wiring diagram on the website, it shows a 16A fuse serving the wiper and flashers, so allowing 3A each for two bulbs (no hazards than) it could be more like 6A or so. Unless you can get that sort of current through, the wirper motor won't work! A 6V 18W indicator bulb carries 3 amps at full brightness. Try a 6V headlight bulb maybe? At 6 or 7 Amps, it should be able to pass enough current for the motor to work. Not sure what you do with the heat produced, but maybe if it's actually raining, some demisting warmth would be handy!

The 6V rheostat should drop some volts, and the resistance wire is quite thick. Just make sure it's not getting too hot or you may get other problems.
Dave.

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