Page 1 of 2

Ammeter not reading.

Posted: Sun Oct 08, 2023 8:54 pm
by Ian.Lindsay
Just got my first Ariel (1954 Huntmaster) and still checking stuff over on it before taking it out on the road. It arrived with a totally bricked battery as it hasn't been run for over a year and so I put a new one in it this weekend. However, the ammeter also seems to be dead. The needle doesn't shift from zero when I put the lights on. When I start the bike it still shows zero. I'm new to all this. How do I best test where the problem is? If it's just the ammeter that is knackered how do I get this out of the headlamp unit to test it? Presumably, looking at the bike, I need to take the headlight unit out of the housing and looks like just one screw in the top of it to release the ammeter through the top.

Re: Ammeter not reading.

Posted: Sun Oct 08, 2023 9:22 pm
by will_curry
Some photos would be helpful.

In the standard layout the ammeter fits into the light switch panel which in turn
fits into the headlamp shell. There are three (I think) screws holding this panel
to the headlamp. Do disconnect the battery before trying to remove the
panel.

Ammeters were retained by bending tabs on the ammeter's bezel - rather tacky.
Better quality ammeters often have a U-shaped clip to retain them.

Re: Ammeter not reading.

Posted: Sun Oct 08, 2023 10:22 pm
by Ian.Lindsay
Here you go. The light switch sits underneath the speedo on the top of the headlamp housing. Doesn't have the panel like the newer Huntmasters.
WbsAjvf4CaM4FYiHRjZMcINX005rR4SBMiccmzVD (1).jpg

Re: Ammeter not reading.

Posted: Sun Oct 08, 2023 10:50 pm
by Simon.Gardiner
Ian

In your situation probably best to take the headlight out first (the single screw at the top will loosen the retaining clip and the headlight will come off with the rim - might need a bit of gentle persuasion, but the rim comes off from the top first).

You can then get a fairly good look at the wiring inside the shell and see if anything is obviously loose.

HTH

SG

Re: Ammeter not reading.

Posted: Sun Oct 08, 2023 11:08 pm
by Ian.Lindsay
Simon.Gardiner wrote: Sun Oct 08, 2023 10:50 pm Ian

In your situation probably best to take the headlight out first (the single screw at the top will loosen the retaining clip and the headlight will come off with the rim - might need a bit of gentle persuasion, but the rim comes off from the top first).

You can then get a fairly good look at the wiring inside the shell and see if anything is obviously loose.

HTH

SG
Yes I thought it might be just a single screw holding it in. Looks like the one behind it is the one holding the ammeter in. If the ammeter isn't connected then that means the bike won't be charging then. I don't know where in the circuit it is but presumably it forms part of the charging circuit so needs to be passing current through it. The voltage at the battery is about 6.1v and when the bikes running quite a bit more so looks like the charging side is doing something. What should the charging voltage be ideally and how do I check the dynamo and regulator are working correctly? I don't want to cook the battery. Assuming for now that the ammeter is passing through current what could be the cause of the needle sticking on zero?

I could do with a wiring diagram really. I think it's standard 6v positive Earth. Nothing fancy. I suspect the members section has one but I can't see that area as I've only just joined and Roger won't have had time to sort me out a membership number and access to the closed area yet. I have no user manual, service manual or workshop manual for this bike. Hopefully, I'll be able to pick up some useful stuff in the closed area next week.

Re: Ammeter not reading.

Posted: Mon Oct 09, 2023 8:37 am
by simon.holyfield
The ammeter and the switch lives in a separate panel, retained by three screws - one is visible ahead of the ammeter. It's possible your headlight was painted with the panel in place.

Re: Ammeter not reading.

Posted: Mon Oct 09, 2023 9:40 am
by Ian.Lindsay
simon.holyfield wrote: Mon Oct 09, 2023 8:37 am The ammeter and the switch lives in a separate panel, retained by three screws - one is visible ahead of the ammeter. It's possible your headlight was painted with the panel in place.
Have you got a picture of it on your bike please Simes?

Re: Ammeter not reading.

Posted: Mon Oct 09, 2023 11:45 am
by dave.owen
If uts an after market ammeter, it might be a 12v one, used on a 6v system it will show very little deflection

Re: Ammeter not reading.

Posted: Mon Oct 09, 2023 12:15 pm
by simon.holyfield
IanRL wrote: Mon Oct 09, 2023 9:40 am
simon.holyfield wrote: Mon Oct 09, 2023 8:37 am The ammeter and the switch lives in a separate panel, retained by three screws - one is visible ahead of the ammeter. It's possible your headlight was painted with the panel in place.
Have you got a picture of it on your bike please Simes?
If you look down this page, into the W/NG section, there is a picture of my W/NG headlight with the panel off. The next picture shows the panel from the inside:


https://ariel-square-four.blogspot.com/ ... g.html?m=1

Re: Ammeter not reading.

Posted: Mon Oct 09, 2023 12:16 pm
by simon.holyfield
IMAG5219.jpg
IMAG5220.jpg
IMAG5220.jpg (19.9 KiB) Viewed 9191 times
Here you go. That's a repro ammeter - original ones don't have the clamp bracket, but are retained by tabs on the rim as has been said.