TR4/4A Amp Gauge TR3 vs TR4

[Tr3aguy]

Are there any big differences in appearance between the gauges besides that Convex glass on the TR3 dial and flat glass on the TR4 gauge.....

In other words could you use a TR4 gauge and swap out the glass on the gauge and it look right for a TR3? Does the glass fit inside the cover of the TR4 gauge?

I can't seem to find an original gauge for decent money!

 

[TR3driver]

Early TR4 look exactly the same, even including the convex glass. (Might even be identical, not sure offhand). The later ones with the flat glass look somewhat different, mostly because the top of the needle is hidden under a shroud (so you can't see the slot in the faceplate). Moss shows the change point as CT11307/8.

Sorry, don't know offhand if the convex glass will fit the flat gauges, but I think it will.

PS, this isn't the later TR4 gauge, but it does show the shroud over the pivot:

 

[HerronScott]

JP,

The early TR4 (up to CT11307) ammeter with domed glass is supposed to be the same Lucas part number (36264) as the one used in the TR3A after TS60000 and TR3B's but the more common later TR4/TR4A ammeters are very different.

Here's an auction of the later gauges including an ammeter on eBay.

TR4/TR4A gauges

I went back and snipped a picture of the later and early TR4 ammeters for future reference since the auction will go away eventually.

Scott

 

[Tr3aguy]

Thanks guys for all the information, now all I need to do is find one....

 

[TR3driver]

Drop me a PM if you strike out; I might be able to help if you're not in a hurry.