fiat500 said:

Thank-you...but maybe eltri****y it not so simple. Looking at the internal wiring-diagram I see that I'm putting a strain on the motor by repeatedly activating the additional winding which is there to brake the motor when it parks. It's now doing that repeatedly and I'm stressing out that this might cause problems.:bang: ....job on hold.

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Send me a diagram of how it’s been wired and I’ll let you know what I think?

I’m all sorted now with the wipers working reliably and safely. For anyone daft enough to do this my first word of advice is “Don’t!”. Although it’s cheap and simple, in order to do it properly you need a lot of patience and a bit of internal drive to help you over the fiddly bits. It took me much longer than I expected and a lot of trial and error.

Theory: The wiper-motor has a four-pin plug. Wire colours vary but with a multi-meter you will find that there is a wire which becomes live with the ignition turned on and the wiper-switch in the “ON” position, a wire which is permanently live in whatever the switch position, a ground (earth) wire, (probably black) and a mysterious wire which, when the wiper-switch is in the “OFF” position is connected to the ground wire.

The modification works by providing an additional live feed into the first wire mentioned above. This needs only to be a brief pulse of 12 volts because once the motor has been pushed off the “park” position, the permanently live feed will take over and complete a revolution of the motor. It will then automatically park again until the next pulse comes along.

One problem I encountered is that the fourth wire mentioned above allows an additional winding in the motor to apply a reverse “brake” when approaching the park position. This could cause problems when subjected to this sort of repeated use. My solution was to simply remove its spade terminal at the wiper-switch and then to insulate the spade and tie up the wire; the wipers still appear to park properly.

How to get the pulse: In order to get a regular, timed feed to the wipers I used a simple relay assemble bought from eBay. There are loads of these available, some having programmable circuits and LED displays. But I chose a relatively simple one in which the period of time the relay is off and the amount of time it is on are adjusted by screwdriver slots in two variable resistors.

The relay needs a ground wire and a live feed both for its operation and to be supplied to the COM terminal which is regularly switched towards the wiper-motor. It also has two small wires which when connected to each other start the module into operation. When these wires are connected a second time the module is deactivated. It follows that these two wires are extended and connected to a switch. For now I have repurposed the dashboard switch which used to operate the speedometer internal lamp; this means that the internal appearance of the car is unchanged. The ideal switch would be one which did not “latch”; a momentary-switch in which the first press activated intermittent wiping and the second deactivated.

Installation: Other than the two wiring changes described in the “Theory” paragraph, the existing wiring remains unchanged and normal wiper operation over-rides the intermittent should it not be deactivated first. Intermittent operates independently of the regular wiper-switch, which stays in the off position. The relay did not come with any sort of casing so I had to find an appropriate plastic container in which it was insulated and housed. I had already placed a convenient fuse-box close to the wiper-motor, so it was easy to get a fused, 12 volt feed and a ground-wire to the relay.

The trickiest part is adjusting the relay so that it is activated and deactivated at just the right intervals that provide the correct number of wipes at the right interval; sometimes I get two wipes consecutively, depending on the position of the cam that operates the parking-switch.

At the end of the job I spent a lot of time clipping up all of the new wires and anything disturbed by my working in order to guarantee safety and reliability; it’s particularly important to check that the wiper-mechanism isn’t on collision course for your wiring. For all of the effort expended, the achievement of intermittent wiping now seems less impressive than I expected. For a lot of Fiat 500s I suspect that the wipers aren’t even used all that often, so this palava would seem pointless. But in this rainy country (Scotland), where I do so much driving in all weather, I think this is going to be very useful.

fiat500 said:

I’m all sorted now with the wipers working reliably and safely. For anyone daft enough to do this my first word of advice is “Don’t!”. ....................................

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Top marks to that man...
Now.. instead of rebuilding engines in competition with lots of people...
put this all together in a little box with some Instructions and contact all the usual suspect suppliers and offer them the kits...

Bigvtwin996 said:

Top marks to that man...
Now.. instead of rebuilding engines in competition with lots of people...
put this all together in a little box with some Instructions and contact all the usual suspect suppliers and offer them the kits...

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I like fiddling about with anything connected with the Fiat 500, whether it be engines or wipers. Money's not the motivation but of course it would be nice if there was a get-rich-quick possibility.
But I don't think this is one of those...even if I could put a reliable kit together I doubt there would be much demand for it....who goes out in the rain anyway?:devil:

It's not a bad idea to put together as a kit (if you can be bothered!)
I think ideas like that are good if you can sell enough to pay for your development parts at the least.

It's difficult to get an accurate picture of how many people will definitely cough up once the part is made, but you can always ask for people to pay a deposit.

I would happily buy a kit like that and pay a deposit in advance.

I have a few projects I am aiming to finish with a plan to sell at least a dozen so that I can recoup some costs.

MOD500 said:

....................................
I think ideas like that are good if you can sell enough to pay for your development parts at the least. .....................................
I have a few projects I am aiming to finish with a plan to sell at least a dozen so that I can recoup some costs.

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Many years ago I would have parts remade... simply because they were unobtainable or such poor quality..
It was only as a hobby to get things I wanted.. I would as you say "sell a few" to recoup some costs...
More and more these days I am thinking of doing the same, trouble is most of teh people I used have sadly shuffled off this mortal coil.....
But i have been looking at new ways of doing things, and having dabbled a little I do feel that owners of some marques have a different attitude...
On the Etype Forum there is a guy who remakes so many parts that the main spares dealers are taking note that "It does the Jn, it works, it's almost right" is no longer good enough...
In addition things that make everyday classics more useable are becoming more popular..
123 Distributors and Dynalite alternators cost more than originals but they sell well...
If Peter can buy sufficient parts to create one kit and be able to reproduce it easily that is the only investment... the hardest part is the instructions, as several languages would be a big requirement..
Then take photos and simply contact the main suppliers....

A few terms and conditions... include a non liability - owners fit at their own risk...
you could even set a minimum price you would expect them to sell for so as to avoid undercutting etc....
Then decide a minimum order number and see what the response is....
You could even make a few and put them on ebay....
ohh as an extra I would test them and seal them in a plastic case....

MOD500 said:

It's not a bad idea to put together as a kit (if you can be bothered!)
I think ideas like that are good if you can sell enough to pay for your development parts at the least.

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Development costs have been less than £8.00, but don't tell anyone.

Today I decided to play with the other timer module I bought. This seems more user-friendly because it has programmable buttons and an LED display for the modes and timings. After abit of fiddling about I got it to work.

The advantages of this one extend to the fact that it's either on or off, so a straightforward toggle-switch is ideal...no need to change anything. It's also more precise in timing selection than the analogue dial on the other relay I have been using and less sensitive to voltage changes as the engine speeds up.

So this one's a goer and if I did produce one for anyone else I would have to move up to one which was more user-friendly; how about the one in the enclosure?

fiat500 said:

Development costs have been less than £8.00, but don't tell anyone.

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Ohhh now I know, I would target price that at £24.99 + £2.50p&p

fiat500 said:

....................
So this one's a goer and if I did produce one for anyone else I would have to move up to one which was more user-friendly; how about the one in the enclosure?

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Looks too modern for me...
could you not include a small "trimmer" resistor where people could tailor the delay to what they want? then leave it...


My 1967 Lotus elan has a simple variable resister system for variable speed wipers.. a standard Lucas system for many cars from the 60s....

I've been waiting for weeks for the arrival of a couple of samples of the component previously photographed.

In the intervening time, the original relay decided to get into conflict with the electronic indicator relay and gave up on me. I'm not sure if this was because of the fluctuating voltages; the relay can handle a wide range upto 30 volts, but it may have been due to mis-wiring and power surges when I was experimenting with the fit.

Anyway, the improved model was a direct replacement and is a bit smoother and more positive in operation. I would need months of road-testing if I was daft enough to try to market this as a system. Even if supplied as a partially assembled kit, the fitter would really need to know what they were doing. Even if I was cheeky enough to try to make a killing on the price, the components are so cheap there wouldn't be much profit.

So if I can achieve a few months of reliable use I'll write up the wiring details and illustrate how it's done.