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Waterproof(ish) relays
DIY Si - 8/5/09 at 10:43 AM

My car seems to have a habit of eating its main beam relay. It's not the wiring or anything like that doing it, it's because of where it's sited under the scuttle panel. If I'm out in the rain, or it rains and I've not got the car sheeted up, the relay can get dripped on. Most of the time it's fine, but eventually it fails. Does anyone know of either a supplier of splash/water proof relays, or a way of waterproofing one. I could move it somewhere else in the car, but it would be lots of bother and were it is now is quite convenient. Any ideas folks?

speedyxjs - 8/5/09 at 10:45 AM

Surely it would be better to try and solve the problem rather than cure the symptoms?

DIY Si - 8/5/09 at 11:17 AM

I agree, but it would mean sealing the scuttle front panel to the scuttle and then sealing the lot down on the chassis. Only thing is the two panels can not be removed/moved together, as the wiring and fuel pipe runs through front panel.

r1_pete - 8/5/09 at 11:18 AM

Can you not move the relay, or fabricate a cover for it?

DIY Si - 8/5/09 at 11:20 AM

I could move it, but it would a fair bit of bother, and it's nice and easy to reach where it is. A cover or similar could be an option though.

blakep82 - 8/5/09 at 12:00 PM

maybe one of those plastic boxes you get from maplins, with one face cut out for wires (the hole goes at the bottom in the car) you put the relays inside the box, keeps the wet off

iank - 8/5/09 at 12:04 PM

I'd agree with Blake, a decent (IP65 or similar) box with all the relays and fuses inside, wiring going in through a suitable gland/grommet. That's my current plan for keeping the electrics dry when splashing through muddy puddles.

ken555 - 8/5/09 at 12:49 PM

Put it inside a balloon.

Feed it in the neck, then cable tie up.

Common practice in the RC Car world.





[Edited on 8/5/09 by ken555]

David Jenkins - 8/5/09 at 01:11 PM

Most of my relays live in a box like this - this one's from Vehicle Wiring Products, but loads of people sell them:



It's reasonably waterproof (it has a rubber seal) - certainly splash-proof.

britishtrident - 8/5/09 at 01:34 PM

Relays should always be mounted with the pins facing down.

David Jenkins - 8/5/09 at 01:43 PM

quote:
Originally posted by britishtrident
Relays should always be mounted with the pins facing down.


That's a bold statement!

I've seen them in almost every orientation apart from upside-down in all sorts of tin-tops. This is both under the bonnet and in the passenger compartment.

If there's a chance that they will get splashed then it is a good idea to mount them pins downwards as it means the relay cover won't have any seams exposed to falling water and water can drain out of the connectors, but there's no compulsion about it.

02GF74 - 8/5/09 at 01:48 PM

http://www.britishparts.co.uk/.sc/ms/dd/Jaguar%20XJ8%20-%20XJR--Electrical/556/RELAY £ 7.19

TBH, you should seal up the relay youself with PU - the pins, from memroy, are moulded into the base and the base clips to the relay case.

Place it in a plastic bag, and job done.

wilkingj - 11/5/09 at 12:47 PM

as its under the scuttle....

Locost approach would be to cut the bottom of a round plastic bottle (old style fairy liquid or similar - not the drinks bottle type of plastic)

then unbolt the relay from the scuttle, a quick hole in the side of the plastic cup shaped bit, and you have a waterproof cover (put on opening downwards with the relay up inside it).
I would also fit a new relay, and seal with some hot melt glue - wonderful stuff!.

Cheers