Sorting AH Tourer Amp Meter

[GM6VXB]

New to the forum.

Bought myself a 1933 AH tourer last week. Original registration was VT 9569 but now is registered as 363 XUN.

Sorted out quite a few problems already, (would not start, lights not working, indicators faulty) but have a problem with battery charging.
Suspicion is wiring but found the amp meter was not working and on closer inspection was only on the car as a 'hole filler'. No wires
to it, and no connections to fit them onto !!.
Looked around but cannot trace an original meter (unobtanium ?). Anyone know if anywhere holds one in stock or do I resort
to plan 'B'' fitting a lower amperidge one off a motorbike.

Very cold today but will be out doing more work/checks tomorrow.

Martin,
NE Scotland

["Slack Alice" Simon]

They come up on Ebay from time to time.

I think there is one on now, but my car isn't here to check that the 2" diameter is correct.

If too pricey, there is at least one more that isn't right but looks the right period, cheaper.

[Howard Wright]

Hi Martin

Welcome to the forum.

The ammeter in the SM5 switch box is not 2” but a bit less.  As Simon has said they come up from time to time but tend to be pricey.  Not a purists solution, but for my Special I opened up the hole in the switch panel face and fitted a brand new 2” gauge.

Cheers

Howard


  IMG_1434.jpeg (Size: 133.59 KB / Downloads: 289)

[Mike Costigan]

A 1933 car will have the separate ammeter in the main dash panel - I think it's smaller than 2":

   

[John Cornforth]

Hi

Some versions of ammeter had no terminals. They relied instead on sensing the magnetic field around a current carrying wire. The (insulated) wire would be held in place across the back of the instrument with a clamp. Sometimes there would be an extra loop of wire to double up the sensitivity.

The outer diameter of the chrome bezel is 1.75 inches for the type in the post above.

[GM6VXB]

Thanks for that John.
This could be the type, unfortunately glass is broken, and needle  is offset from the zero point
and sticks.
Nothing to loose, so will try to take it apart to see if the internals are fixable. If they are then I might be
lucky and find an old meter with the same size glass on my father in laws farm.

[GM6VXB]

Very happy to say the ammeter is fixed.
Managed to get it apart and quite rusty inside. Cleaned out as much as I could and
the put some fine oil on the bearings (very fiddly) and movement now worked without
sticking.
Did a test on one of my 10 Amp current limiting PSU's and with two loops around the
back the meter worked.
Spent a couple of hours on my Father in Laws farm and 'eventually' found a meter with
the correct size glass. Home and put this in.
Meter now back in the car but shows the dynamo is not charging (tomorrows job) but
does show discharge with all the lights on.
So as they say 'one step foward, one step back'.

Martin, GM6VXB

[Ivor Hawkins]

Dynamo not charging Martin?

That’s perfectly normal, I haven’t had a charge out of my dynamo for years!

Seriously though, I’ll have to sort it out at some point but with an occasional charge, the battery does fine.

Ps. What does GM6VXB mean?

[GM6VXB]

Ivor,

Had just started checking dynamo and cut out when Grandchildren arrived to see the new toy.
So not got much done today.
Suspicion is dynamo but will hopefully have time tomorrow to do some tests.
Fingers crossed it's only brushes !.

GM6VXB is an amateur radio callsign. Been licenced since the mid 80's.

Martin, GM6VXB

[AustinWood]

Our dynamo hasn't worked for a very long time. We have a battery conditioner in the garage so always start with a full charge. Should be good for more than 400 miles. We have LED lights too.