Film-Tech Forum ARCHIVE: Sticky dowser solenoid

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Posted by Jonathan Wood (Member # 4614) on 05-06-2017, 08:10 AM:

Hi all

Would anyone know why a dowser solenoid keeps sticking open after the close button is pressed.? It's a Vic 5 and the relay and bridge rectifier are all fine . The down button opens the relay fine and shuts off the DC. You then need to give the dowser a little tap and it shuts. Once it's shut and no current running through it , it moves up and down very easily so I don't think it's mechanical. Could it be that it's remaining slightly magnetised? Thanks as always , Jon

Posted by Monte L Fullmer (Member # 2797) on 05-10-2017, 04:11 AM:

Simple mechanical issue with this dowsers:

It's usually the dowser lift arm that comes out of the housing.

The solenoid really slams that arm up when opening and the arm hammers against that stop

The metal where it strikes the stop pin gets mushroomed out where it drags against the casting and hangs up the arm.

File down that mushroom and you should be good to go.

A chronic issue with V-5's

Good luck - Monte

Posted by Jonathan Wood (Member # 4614) on 05-12-2017, 02:03 AM:

Thanks Monte! That's very helpful , I'll give it a go.
Cheers, Jon

Posted by Allan Lyman (Member # 9449) on 05-12-2017, 04:23 AM:

The dc magnets had a tendancy to keep its magnetic after power off.I dont remember if adjusting the buttom plastic screw helped,or if I simply had to change it.It sounds like this is your problem.
alan

Posted by Jonathan Wood (Member # 4614) on 05-12-2017, 08:27 AM:

Hi Allan
I think you're probably right as I examined the arm following Monre's suggestion and it appears ok . It does feel like there is still a slight magnetic pull even after the dc is switched off. The RCM relay is also intermittent in its operation so I think I need to replace this too.
Thanks , Jon