Indicator problem.

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Bison
Posts: 132
Joined: 27 Mar 2013 10:49
Location: West Lothian

Indicator problem.

Post by Bison »

Hello Folks,
Any ideas about this?.
Stock CEV indicators, new indicator unit, stock switches
Indicators work fine with ignition on, when you start the engine they are very erratic. Ignition on, engine not running, press the stop light, it works, but pulses slightly with indicators, all earths are spot on, but this is a sign of a bad earth, start engine up, the indicators go haywire . It has blown the fuse on the indicator/stoplight fuse holder, replaced, still does the same, indicators erratic, flashing sometimes, then fast, then not at all, replaced the (generic) two pin flasher unit, which was new anyway, the same. Fuse is still OK, Checked the voltage (but not the amps), going into the (new) battery, 13.4v to 13.8v, steady.

Any ideas?
Alan.
'It must be a .....'
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Joined: 12 Sep 2010 12:25

Re: Indicator problem.

Post by 'It must be a .....' »

Hello, which type of CEV indicators are on the bike?
Bison
Posts: 132
Joined: 27 Mar 2013 10:49
Location: West Lothian

Re: Indicator problem.

Post by Bison »

Black CEV same as the standard ones except black, fom a Servetta ( lambretta). I have the same ones on my other Sport, no problems there.
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Daddy Dom
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Location: Auckland, New Zealand

Re: Indicator problem.

Post by Daddy Dom »

Although I am a self-confessed electrical numbskull, all I can think of is that Lambrettas are 6v and Morini 12v. What bulbs are you using? Also, is your idiot light working properly and are there any LEDs in this recipe, including the idiot light?
DD
MRC 3082½
julianharty
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Re: Indicator problem.

Post by julianharty »

To help isolate the cause, how about running the earth for the indicators back to the battery's negative terminal with a wire? You can even test each indicator bulb separately by running one wire to the positive terminal and the other to the negative terminal. They should light consistently and remain lit for minutes if wired directly. This should hold regardless of whether your engine is running or not (test both with and without it running).

Do please also let us know exactly what bulbs you're using in the indicators: are they 12V 10w?
Also, which type of indicator flasher are you using? one that heats up to break the contact (the standard type for decades and why the wattage of the bulbs affects the rate of flashing) or an electronic one?

My instinct is firstly that something's not quite working with the 'earthing' (which is actually the power return to the negative). The second is that your regulator might be faulty and allowing AC onto your +ve circuits that's happening to mess up your indicators and blow your fuse.

Good luck resolving this. I'm happy to offer more suggestions.
Bison
Posts: 132
Joined: 27 Mar 2013 10:49
Location: West Lothian

Re: Indicator problem.

Post by Bison »

Hi Folks,
Thanks for all the suggestions.
Yes, 12v 21W indicator bulbs, a two pin ordinary (non electronic) flasher unit (should it be three?), tried earthing the bulb bodies separately, no change, checked the earths to engine/ battery/ frame all ok. There does seem to be an earthing problem though because the stop light does dim/brighten when the indicators are on without the engine running, tried a separate earth to the stop light too, no change. I tried cutting the flasher unit out of the circuit, the bulb stays on, , engine running or not. I tried an electronic unit one from my Saturno, nothing, just buzzed. Sorry, I should have told you all this in my first mail. I'm beginning to suspect the regulator, apart from that dimming/brightening stop light which throws me off. I'll double check the regulator earths again.
Alan.
Bison
Posts: 132
Joined: 27 Mar 2013 10:49
Location: West Lothian

Re: Indicator problem.

Post by Bison »

OK, lets get all the details down. It's an early electric start model, I didn't fit the starter motor or the relay, the indicators each have a separate earth wire, going onto the mudguard bolt at the rear, and the headlamp shell at the front. Do the earths have to be separated?, IE, lh and rh?when is an earth not an earth?
Alan.
julianharty
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Re: Indicator problem.

Post by julianharty »

What's the flasher unit rated at? by this I mean, does it have something like 2*21w/12v written on it? From memory many Morinis have lower wattage bulbs and flashers 10w if I remember correctly. If the bulbs consume more (21w consumes more than 10w) then the flasher will have to work harder (the internal bi-metal strip heats up faster) and may cause some problems that make the bulbs flash erratically.

If your measuring device (generally most people use a multi-meter) has a setting to check resistance you can check the resistance between two 'earth' locations. Perhaps the rear-mudguard has a poor electrical connection to the rest of the bike? The reading should be close to 0 ohms.

Earth refers to the ground - the actual ground that you and I stand on. Confusingly many people refer to the motorcycle's frame and a bike's electrics as being earthed. Technically they're unlikely to be. I might be overly pedantic. What you do need are excellent connections back from the various electrics back to the negative terminal on the battery. In many cases (including on your Morini) these will be via one or more metal parts such as a mudguard or frame. What I suggested earlier was to bypass the connection via the metal parts by running an extra wire back from each indicator to the battery's negative terminal. This needs to be the return (the same wire that's used to connect to the mudguard / headlight) rather than the power which comes via your indicator switch (in the left hand switch gear unless you've a very unusual Morini) which - in turn - gets its power from the flasher unit.
Bison
Posts: 132
Joined: 27 Mar 2013 10:49
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Re: Indicator problem.

Post by Bison »

Hi,
Yes, I clipped a wire to the rear mudguard bolt where the ground wire goes to the battery ground, and did the same with the ground in the headlamp, no joy. I did the same from the bulb holders to the battery, no joy. Interestingly my other Sport has the same flashers and wattage bulbs, no problems. but not the same switch gear. The flasher unit is a generic one from M&P, 12v 23W. Just checked the resistance, zero, or very close, the meter reads .002 ohms when probes are pressed together, and the same from indicator stalk to engine case and battery, the meter needs calibrated by the looks of it
Alan.
julianharty
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Location: High Wycombe Area (Bucks)

Re: Indicator problem.

Post by julianharty »

The following is unlikely, but perhaps just might help...

Check each of the connectors, particularly to the combined junction and fuse box. Perhaps the vibration of the engine is causing the problem rather than there being an electrical fault? I don't think this is likely, but sounds like you've covered many of the basics.

The other thing to try is to disconnect the brown lead from the regulator/rectifier to the junction box (of whichever lead takes the output from the regulator/rectifier to the rest of the bike). This should mean the engine isn't providing power to the electrical circuits and therefore may help identify whether having the power from the alternator + regulator/rectifier is affecting the flashing rate.
Oh and I'm assuming you'll do this as a quick test and then reconnect the relevant lead otherwise your battery will run down eventually...
Bison
Posts: 132
Joined: 27 Mar 2013 10:49
Location: West Lothian

Re: Indicator problem.

Post by Bison »

Aha, now that's a great (and I'm ashamed to say obvious) idea, I'll isolate the charging system and see what happens. A problem shared and all that!
I did check the voltage over the battery terminals when it was running and it was 12.8v to about 13.8/14V when revved, but of course that's voltage, not amps.
Thanks,
Alan.
Bison
Posts: 132
Joined: 27 Mar 2013 10:49
Location: West Lothian

Re: Indicator problem.

Post by Bison »

Disconnected the brown wire from the regulator, made no difference, still behaving randomly when running. I'll be taking the fuse out of the equation next, see if it a bad connection, I'll connect the wires together.
Alan
julianharty
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Joined: 15 May 2016 16:34
Location: High Wycombe
Location: High Wycombe Area (Bucks)

Re: Indicator problem.

Post by julianharty »

Sounds like you're at least learning what makes a difference and what doesn't. Surely the problem can't hide forever given the deductive work you're doing :)

Another idea: you could try measuring the voltage of the output of the flasher unit with and without the engine running. Your multimeter might not be fast enough to show accurate voltage / current but you might see a different pattern of readings with and without the engine running. Is the output erratic? I'm guessing it will be, the question is then whether it's erratic because of problems related to the electrical load (given how the flashers often work, they respond to the load in order to disconnect the power to the indicators roughly once or twice a second) or because of a flaw in the power supplied to the flasher unit.
Bison
Posts: 132
Joined: 27 Mar 2013 10:49
Location: West Lothian

Re: Indicator problem.

Post by Bison »

Hi Folks,
I'm heading down the vibration route now. I cable tied the rubber mounted flasher unit to stop it shaking around, no change, next is have a detailed look at the (original) switch to see if there's anything loose in there.
Alan.
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