The switch is mounted on a bracket with pressed rivet like posts. It was all loose so I removed the switch and repressed it into the bracket.
If the switch is faulty,is there a suitable replacement?

Been taken away to do other domestic chores will look further tomorrow.

Thanks so much for your assistance and advice so far.

Andrew

Update on turntable. June 2019
The main culprit was the switch. I removed it and pulled it apart.
Next was work out how it makes electrical contact. Rudimentary action of roller pin in middle of switch making contact with terminals.
I cleaned contacts and roller then pulled spring apart to increase tension when switch is released.'
Turntable switches on correctly and switches off.
I found 1 lead on the phono cartridge wiring to resisitors inside was open circuit. Wire replaced.

I removed cartridge (ACOS HI G ) and found terminals were very dirty and 78 stylus worn out. 33 stylus looks good bit very dirty.
Can't get any output when switching to phono input of radio.

Any idea where to get a replacement cartridge if I can't get this one working. I have found replacement stylii but nothing else.

The Acos Hi-G is a crystal cartridge and the crystals usually go bad (disintegrate) after a long period of time so, even if you happened to find a new old stock one, it would probably be no good by now.

Some of those early turntables were a mechanical abomination, The one in the Radio Clubs HMV being one of them. They did get a lot simpler into the sixty's especially BSR. But beware, I don't know what they used to lubricate some BSR units, but left for a long time, It welded the platter to its arbor & hell and damnation could not separate them.

This sort of thing can also result (as before) from mixing grease types & brands due to different chemicals being used to get spec. So rid it of all old grease soap; before using new stuff, if you do not know the brand. Philips tended to use Royal Dutch Shell. Virtually everything using Shell here, is really old & still going.

Thanks GTC, I pulled the cartridge apart and you are correct,the crystals are crumbling.
The main reason was to see how it worked and to salvage the brackets if I need them when I find a replacement cartridge.

Andy, there is a commonly available ceramic cartridge made for later Garrard changers that looks very different but will fit. I bought my last one at a vintage vinyl store in Surry Hills.

I have one of those. Mine is a U63A 78rpm only. You gently push the arm to the right and the turntable starts, then you put the needle on the start of the record and when it reaches the end it shuts off the turntable. If you push the arm halfway through the record it'll shut off, but ifyou let it play it should stay the course as the arm moves nice and slowly when playing, slow enough not to trip the mechanism before the end of the record. Mine takes Columbia 99 needles or HMV silent stylus; both rare as hen's teeth although I found a brand new pack of ten from Italy on eBay. Each needle is chrome-tipped and rated for 100 plays, so I have a little notebook where I keep a score of plays for my needles. The radio is a real beauty, pulls stations really well, in fact I can get 1325 Adelaidein Clare and none of my other radios can without much noise and static. The turntable takes about 5 minutes to warm up, running very slow until it does, but once warm plays perfectly until next time when it's been off for longer than a few hours and needs to warm up again.

Hi Jamie

Your turntable motor needs a lube and rubber jockey wheel needs a scrub. Should come up to speed immediately.