Relays coming loose in PDC

[JBCumminatya]

Bumped the starter to listen for "new" lift pump cycling. No sound.



Pushed down relays in PDC. Bumped the starter again. Heard the lift pump cycle.







Will be getting CRC cleaner and dielectric grease to ensure electrical contact.



If these components worked loose because of vibration, has anyone tried to hold these components in place.

Could a piece of compressable foam be placed under the PDC cover or do the components require the air to circulate to disipate any heat created by these components?

 

[BK]

in manufacturering of electronic thingyies..... we use RTV to help hold things like that down or keep em in place. Get some GE5000 from Homedepot (clear 30 year best silicone II, if you read the small print enough you will find the "GE5000" on the tube somewhere). Use rubbing alchol to clean off the relay case and the surface around it you want to gop it to. Let dry.



"Spuugh" on that RTV and let try for a few hours before you put the case cover back on so the fumes get out. If the fumes are trapped from the initial cure of the GE5000, they can be a little bit corrosive... just a little. I'm being real. . it's not horribly corrosive, but can be just a bit. So dont seal around the entire edge of the relay to the case... leave say the corners open for the gasses to escape during cure.



Dont force the RTV down into the cracks too much. The bigger the blob the better the job, yes... but if you push it into the cracks too deep and get it into the sockets for the relay you'll have a bigger problem to deal with. So surface blobs work well enough.

If you force it into the space between the casing and relay, the relay will be harder to get the relay out in the future. The rtv normally comes off easy if you need to remove the relay for any reason.



If you use something via pressure to hold it down you may apply too much pressure and break the case or relay in some way.



Been designing in RTV for shake and vib relief for over 20 years.