Charging system solutions

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Kneeslider
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Charging system solutions

Post by Kneeslider »

Hi everyone. Just the other day my 356 suffered with the dreaded red light on charging system problem, which looks to have cooked the dynamo. Is there anyone out there who can do a rebuild in a fairly short space of time? Or failing that, suggest somewhere to supply a rebuild kit, then I can rebuild it myself? I have seen a few for sale, but they all seem to be 12v. I'd like to keep my car 6v.

Looks like I'm also going to need a new voltage regulator. Electronic or mechanical, I'm not fussed.

I've got a trip to Le Mans booked for early next month and I was planning on taking the 356, but the 997 might have to step in instead.

I'd also be interested in any opinions about trying to make the charging system of their 356 more reliable without going 12v.
'65 356 SC
'91 Ducati 750/900ss mongrel
1963 Velocette Viper (mostly) with '39 KSS OHC engine
'05 997 C2
1954 FB Mondial 200 Extra Lusso
neilbardsley
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Re: Charging system solutions

Post by neilbardsley »

The simplest problem my be that your bushes are worm and need replacing. Take the band off and use a fibre pen to clean the communator. Check the bushes while you are there. If that doesnt improve the charge then yes you can take them apart and clean.

If that doesn't work these people can do a full rebuild. Including a rewind (if needed)

Robson & Francis Rewinds
020 7733 2353

https://g.co/kgs/mqvHAF

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“A REMINDER. I would be grateful if those members who have borrowed bits from me in emergencies (e.g starter motor, oil cooler, etc) would return them and/or contact me”. – Chris Turner RIP
neilbardsley
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Re: Charging system solutions

Post by neilbardsley »

There is also a 6v alternator but it isn't cheap but only about £300 more than a rebuild

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“A REMINDER. I would be grateful if those members who have borrowed bits from me in emergencies (e.g starter motor, oil cooler, etc) would return them and/or contact me”. – Chris Turner RIP
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Hugo 356
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Re: Charging system solutions

Post by Hugo 356 »

Couple of suggestions

Reg light:
https://s3.amazonaws.com/ClubExpressClu ... JEHNVDY%3D

Testing generator:
https://s3.amazonaws.com/ClubExpressClu ... QjDIgDc%3D

The late great Rob at Broadway Electrical used used to re-build generators, may be worth contacting them?

In the US for generator & regulator re-build Doug Darrah, (Formerly ABC Partswerks) Phone: 920-378-5538 email: mrdarrah@aol.com

http://www.sparkingplugs.com/resources/ ... +Smith.pdf

http://www.sparkingplugs.com/resources/ ... th+Gen.pdf
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neilbardsley
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Re: Charging system solutions

Post by neilbardsley »

"The late great Rob at Broadway Electrical used used to re-build generators, may be worth contacting them?"

Rob used the place I recommend for rewinds so you will get similar good service

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“A REMINDER. I would be grateful if those members who have borrowed bits from me in emergencies (e.g starter motor, oil cooler, etc) would return them and/or contact me”. – Chris Turner RIP
Kneeslider
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Re: Charging system solutions

Post by Kneeslider »

Many thanks for all your replies.

I can't seem to open the Hugo's links for Red Light and Testing the Generator... The sparkingplug links to how to take apart the generator are excellent.

Neil, I have contacted Robson and Francis via email to see if they are able to rebuild my dynamo, so hopefully I can get the car back to roadworthiness soon.

Just a bit of further background, I had fitted new brushes to my dynamo some months ago, as they were looking worn. I strongly suspect that the windings have got too hot at some point and the solder has come off the wiring to the commutator.

If so, then this is the second time this has happened. First time, I had assumed that it was caused by a mismatch between the rated output of my generator (which I discovered was an earlier '54 produced model) and the silver can 2 coil late type voltage regulator which is OEM for a C car. I bought a used dynamo which seemed to be in excellent working condition, and replaced the voltage regulator with a NOS item. After carefully adjusting the charging voltage, it has been trouble free for several years, until now.

I have read up a bit on how the mechanical VRs work, and testing and adjusting the output voltage isn't too difficult, I have a basically stock electrical system on my car, without any more additional load than it was designed with, but it would be nice to be able to get to the bottom of the problem, and have a reliable solution for planning long distance trips. Maybe this time it was caused by the dynamo just being a bit old?

Perhaps an electronic solid state VR is the way to go. Some on the Registry website in the USA advocate using the earlier type of black cased VR, as this has 3 coils, and is capable of limiting output current, thus protecting the dynamo from this sort of failure.

The best solution looks to be an alternator, that would solve all the problems, and all electro mechanical sources of un reliability would be dealt with, but until now, I had no idea you could get them for 6v systems. Do you have any leads about this Neil? All my searching seems to turn up are 6v to 12v alternator conversions. I'd still like to keep my car 6v.
'65 356 SC
'91 Ducati 750/900ss mongrel
1963 Velocette Viper (mostly) with '39 KSS OHC engine
'05 997 C2
1954 FB Mondial 200 Extra Lusso
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