Wem copicat Watkins ic900 varispeed motor noise - UK Vintage Radio Repair and Restoration Discussion Forum

pentoad · 10th Apr 2021, 3:11 pm

This is more or less the same as the belt drive ic400 varispeed
There is a fair amount of whirring noise coming from the motor (not the fly wheel) I'm not certain how much is acceptable as I don't know what it was like when new.
I have oiled the bearing which is accessable.
Not sure if replacing the rubber grommits mounts would make a difference.
Should I be thinking of a replacement?
I would be grateful for a reply from anyone who has worked on this model.

TIMTAPE · 10th Apr 2021, 9:39 pm

Are the mounting grommets broken or gone hard? They should be supple I suspect. If unsure perhaps temporarily remove the motor to see how noisy it is mechanically decoupled from the mounting plate. Or maybe just try to temporarily support its weight so it doesnt bear down on the grommets.

fetteler · 11th Apr 2021, 12:17 am

I bet you can't hear the motor whirring when you turn your amp up to number 11!

Steve.

Techman · 11th Apr 2021, 12:42 am

I'm with fetteler on that one - wind up that volume!

Sorry, not very helpful, but it had to be said.

I would do as TIMTAPE suggests first of all...then wind up the volume.

pentoad · 11th Apr 2021, 11:05 am

I'm not sure if the motor noise or vibration would contribute to uneven tape transport bearing in mind it it is belt driven. The other concern is that the vibration could transfer to the heads via the fascia plate. I am hearing warble as the the repeats decay, having said that it the belt seems slack and should be replaced, although it seems to work.
Would a new motor be silent though?

G6ONEDave · 11th Apr 2021, 12:13 pm

All the motors that I heard were rather noisy due to being run at high speed but should not be to noticable when operating inside the case. Check all the moving parts in the tape path for wear and a tighter drive belt. Drive belts and tape loops were common replacement parts but given the age of the unit, it might well be worth checking the heads for wear as well.

Dave

Techman · 11th Apr 2021, 12:33 pm

I've got a couple of echo boxes. The one like yours is a much earlier valve one from the very early sixties (or even late fifties, I can't remember) and it hasn't been touched for years and is buried in the back of a cupboard awaiting restoration, if I ever get round to it. I'm not familiar with yours, but the first thing I found on a quick search just now turned up this article linked to below, which I didn't read through, but noticed that it mentions, to quote - "The main problem with this one was a loud mechanical hum while the tape was running. It was cured by stripping out the motor and lubricating both end bearings with sewing machine oil. Oddly enough, it turned out to be the top one causing the trouble"...I would guess that you've probably already found and read this page if you've already done a bit of research of your own. Note that both bearings were lubricated, not just the accessible one, although that's the one that you've oiled which was said to be the cause of the noise.
https://www.backfromthesixties.co.uk...400-vari-speed

pentoad · 11th Apr 2021, 6:00 pm

It's all lubricated now and sounds a lot quieter, just whirring a little bit

10th Apr 2021, 3:11 pm	#1
pentoad Hexode Join Date: Feb 2011 Location: Newcastle upon Tyne, Tyne and Wear, UK. Posts: 280	Wem copicat Watkins ic900 varispeed motor noise This is more or less the same as the belt drive ic400 varispeed There is a fair amount of whirring noise coming from the motor (not the fly wheel) I'm not certain how much is acceptable as I don't know what it was like when new. I have oiled the bearing which is accessable. Not sure if replacing the rubber grommits mounts would make a difference. Should I be thinking of a replacement? I would be grateful for a reply from anyone who has worked on this model.

10th Apr 2021, 9:39 pm	#2
TIMTAPE Octode Join Date: Jul 2006 Location: Perth, Western Australia Posts: 1,969	Re: Wem copicat Watkins ic900 varispeed motor noise Are the mounting grommets broken or gone hard? They should be supple I suspect. If unsure perhaps temporarily remove the motor to see how noisy it is mechanically decoupled from the mounting plate. Or maybe just try to temporarily support its weight so it doesnt bear down on the grommets.

11th Apr 2021, 12:17 am	#3
fetteler Octode Join Date: Jul 2011 Location: Staffordshire Moorlands, UK. Posts: 1,479	Re: Wem copicat Watkins ic900 varispeed motor noise I bet you can't hear the motor whirring when you turn your amp up to number 11! Steve. __________________ Those who lack imagination cannot imagine what is lacking...

11th Apr 2021, 12:42 am	#4
Techman Dekatron Join Date: Nov 2009 Location: Lincolnshire, UK. Posts: 5,000	Re: Wem copicat Watkins ic900 varispeed motor noise I'm with fetteler on that one - wind up that volume! Sorry, not very helpful, but it had to be said. I would do as TIMTAPE suggests first of all...then wind up the volume.

11th Apr 2021, 11:05 am	#5
pentoad Hexode Join Date: Feb 2011 Location: Newcastle upon Tyne, Tyne and Wear, UK. Posts: 280	Re: Wem copicat Watkins ic900 varispeed motor noise I'm not sure if the motor noise or vibration would contribute to uneven tape transport bearing in mind it it is belt driven. The other concern is that the vibration could transfer to the heads via the fascia plate. I am hearing warble as the the repeats decay, having said that it the belt seems slack and should be replaced, although it seems to work. Would a new motor be silent though?

11th Apr 2021, 12:13 pm	#6
G6ONEDave Octode Join Date: Dec 2019 Location: Owston Ferry, North Lincolnshire, UK. Posts: 1,704	Re: Wem copicat Watkins ic900 varispeed motor noise All the motors that I heard were rather noisy due to being run at high speed but should not be to noticable when operating inside the case. Check all the moving parts in the tape path for wear and a tighter drive belt. Drive belts and tape loops were common replacement parts but given the age of the unit, it might well be worth checking the heads for wear as well. Dave __________________ Quote "All is hyperthetical, until it isn't!" (President Laura Roslin, Battlestar Galactica)

11th Apr 2021, 12:33 pm	#7
Techman Dekatron Join Date: Nov 2009 Location: Lincolnshire, UK. Posts: 5,000	Re: Wem copicat Watkins ic900 varispeed motor noise I've got a couple of echo boxes. The one like yours is a much earlier valve one from the very early sixties (or even late fifties, I can't remember) and it hasn't been touched for years and is buried in the back of a cupboard awaiting restoration, if I ever get round to it. I'm not familiar with yours, but the first thing I found on a quick search just now turned up this article linked to below, which I didn't read through, but noticed that it mentions, to quote - "The main problem with this one was a loud mechanical hum while the tape was running. It was cured by stripping out the motor and lubricating both end bearings with sewing machine oil. Oddly enough, it turned out to be the top one causing the trouble"...I would guess that you've probably already found and read this page if you've already done a bit of research of your own. Note that both bearings were lubricated, not just the accessible one, although that's the one that you've oiled which was said to be the cause of the noise. https://www.backfromthesixties.co.uk...400-vari-speed Last edited by Techman; 11th Apr 2021 at 12:38 pm.

11th Apr 2021, 6:00 pm	#8
pentoad Hexode Join Date: Feb 2011 Location: Newcastle upon Tyne, Tyne and Wear, UK. Posts: 280	Re: Wem copicat Watkins ic900 varispeed motor noise It's all lubricated now and sounds a lot quieter, just whirring a little bit