Help - bust in France

[Bud English]

I have an ancient Perkins diesel generator that has a Lucas 17ACR alternator fitted to keep the starting battery topped up. It has no ignition warning light, but the alternator manages to get going just fine all on its own when the old diesel clonks into life.

Some circuits, where it makes no sense to have a visible light, use an in line resistor to perform the excitation function. It's been suggested that adding the correct resistor, in parallel to the light, will prevent a blown bulb from taking your charging system down. I don't remember the correct value off the top of my head but I have it documented in my rewire notes if you're interested.

Found it... 330ohms

[billwill]

Out of pure intellectual interest does anyone have a theory why the alternator light would come on with the ignition off?

Bill's analysis looks correct,

I don't know why I bother Third response above and a method of testing it!

heh, heh... It's not what you say it's the way that you say it.

My many years of writing technical manuals paying off for me ?

[7skypilot]

Keeping everyone in the loop...

I have at least three ACR alternators at home, and a Bosch (much better) equivalent, which has a replaceable, external diode pack, so I didn't pursue the option of a new alternator but bought a new battery. It doesn't fit that well, but will do to get me home. Very helpful guys at Norauto, Laon sold me the battery but couldn't assist with the alternator. They suggested that internet from the UK was the best option!

I have three C-Tec battery chargers/conditioners at home (why, oh why didn't I bring one with me?). I now have four and am using the recently purchased one to keep both batteries charged.

Lessons learnt include what to include in the spares pack (alternator and charger!), visual clues of an alternator failure and that old cars like ours really do rely on the internet to keep them running (like I'm doing now!).

BTB, the other Elan on the rally was a ragtop sprint that the owner had run for forty years. There were few mechanical failures amongst the entrants but a lovely '62 Alfa Guiletta also suffered a dynamo failure.

We're currently staying in St.Quentin and will be looking at some WW1 sites tomorrow before the ferry takes us home to Blighty. Then it's time to replace the alternator and fix a rather annoying exhaust problem before the Sun Rally takes us from the Champagne region to the Mediterranean over 1500km and four days in early November.

Thanks for all your kind assistance.

Don

[jimj]

7skypilot, I was talking to a bloke last week who mentioned the " Sun Rally", a tour through France in November as I understand. It sounds like a nice time of year and route but no-one seems to have heard of it, not even Mr. Google. Have you any contact details please.
Jim

[69S4]

This wouldn't be it would it? - http://www.15-50ac.org/

[Chancer]

Don;

You are right on my doorstep!!!!

Enjoy your battlefield tour!

P.S. I definitely agree about the Bosch vs Lucas alternators.

[jimj]

Stuart, thankyou, that must be it. It doesn`t sound particularly glamorous but nor am I. It looks amazing value and a great time of year for a jaunt, maybe next year. We`ve done the Champagne Rally a couple of times for that (time of year) very reason.
Jim

[69S4]

It looks ... a great time of year for a jaunt, maybe next year. We`ve done the Champagne Rally a couple of times for that (time of year) very reason.
Jim

I hope it's a great time of year for a jaunt as I'm down that way a couple of days after the rally finishes and might even see some of the participants on their way home. Hope your heater works well as the first couple of days could be pretty miserable if winter makes its presence known early.

[Johnfm]

Stuart, thankyou, that must be it. It doesn`t sound particularly glamorous but nor am I. It looks amazing value and a great time of year for a jaunt, maybe next year. We`ve done the Champagne Rally a couple of times for that (time of year) very reason.
Jim

The November Sun Run is a pleasant way to spend few days. Not particularly competitive, nice people and the organiser (James) really puts in lots and lots of effort.

It is very cheap adn the roads are interesting - I particulalry enjoyed seeing parts of Germany and Austria that one wouldn't mormally visit.

As above, website is

http://www.15-50ac.org/

James can be contacted on:

[email protected]

[7skypilot]

To close the topic, the alternator was toast. Battery was just fine, and after a full charge ran from St.Quentin to home (Surrey) with no problem - and it was dark after the ferry. I've also driven about 400k daylight in a Seven on the battery on another 'failed alternator' occasion.

I fitted a Bosch alternator as it allows the replacement of the diode/brush pack as a roadside repair. I now travel with a C-Tech charger 'just in case' as it's lighter than carrying a spare alternator!

Incidentally, the minor niggle with an exhaust 'noise' turned out to be a leaky exhaust gasket. On reassembling the engine at the start of the summer I'd used the correct gasket, Hi Temp sealant but had omitted to torque the exhaust nuts sufficiently (10 - 15'lbs IIRC). Some were barely finger tight! So the worrying noise was nowt more that a leaky gasket.

BTW, how do the experts tighten the exhaust primary nuts under the thermostat housing? I've a Matty S/S exhaust and have had to 'skinny' down a 3/8" ring spanner to fit over a 3/8" K-nut i've used for the two studs under the 'stat housing. This spanner, shortened and bent to clear other exhaust primaries and used with a right-angled open-ended spanner just about works. Is there a better way? I can't fit an appropriate 1/4" swivel socket on the forward of these two nuts.

Off to the Sun rally on Monday - the entry list looks very interesting. We roll from Troyes to the finish at the Col di Turini above Nice. There is everything from 1930's Alvis through Minis, MGB's, Tigers, Porsches, Alfas and includes another Elan (Stephan and Duncan it'll be good to meet you). I'm very much a beginner but have an outstanding nav with me (and winter tyres!). Should be fun!

Very many thanks to all for your help.

[billwill]

BTW, how do the experts tighten the exhaust primary nuts under the thermostat housing? I've a Matty S/S exhaust and have had to 'skinny' down a 3/8" ring spanner to fit over a 3/8" K-nut i've used for the two studs under the 'stat housing. This spanner, shortened and bent to clear other exhaust primaries and used with a right-angled open-ended spanner just about works. Is there a better way? I can't fit an appropriate 1/4" swivel socket on the forward of these two nuts.

.

Small 1/4" socket set using its extension bar.


But this will depend on the shape of your exhaust manifold.

[john.p.clegg]

...and next time you have your head off,replace them with allen screws..

John

[billwill]

...and next time you have your head off,replace them with allen screws..

John

Not an absolute benefit John, because making frequent use of the threads into the alloy head, may end up stripping the thread and mending one of them will be rather expensive.

[john.p.clegg]

Sorry Bill,should have mentioned to heli-coil at the same time...

John

[billwill]

Sorry Bill,should have mentioned to heli-coil at the same time...

John