Todays question - relays

[JPSmit]

I'm thinking that as I reassamble Ms. Triss, a couple of relay's wouldn't hurt. Specifically headlights, horns and driving lght (to be installed)

here is first crack at trying to undertsand the wiring - I have be studying Bentley like crazy!

this is my schematic of the existing wiring for the horns

https://tinyurl.com/3uw4my

this is what I imagine the relay needs to look like.

https://tinyurl.com/44cpc3

at least that is what I gleaned from the Classic Morosports issue where they did it with their Midget.

thoughts? advice?
thanks all

 

[Jim_Gruber]

Here's a good link. https://www.danielsternlighting.com/tech/relays/relays.html

These are simple to install and the difference in brightness of headlights is like night and day.

I got mine locally via Parts Express in Dayton. I think www.partsexpress.com. Relays and Mounting Sockets Plus a couple of Inline Fuse Holders and I think a 20 Amp Glass Fuse, might be a 25 Amp & some Heat Shrink Tubing. Total package with all was < $25.00. They've got a simple Slick Sheet available for hooking up headlight relays. I spliced into the wire pairs right where it comes out of the fabric harness and mounted relays right there. Power came via inline fuse holder connected to the always on source, wire from battery side of the solenoid. Some solder, heat shrink, a little splicing and you are done. Test to be sure you are connected to the High Beam(little light is on on dash)before you do final soldering and heat shrink connections. Don't ask me how I know.

 

[dklawson]

Your second schematic is basically what I have on my Mini's horn circuit.

I also added relays for the headlights as you are suggesting.

Though Advance Auto Wiring is going out of business, their web site is still up for its technical pages. Visit www.advanceautowire.com and click on the "headlight relay kit" link on the left side of the page. The page that opens up will have a schematic for the headlight relay circuit. The relays shown are standard 30A ISO/Bosch relays.

You can buy the relays at most auto parts stores. I buy mine from www.bgmicro.com If you to to their web site and key in the search word "Bosch" you will find their relays and sockets for them. Again, these are the same type ISO/Bosch relays you can buy at any parts store so they are a good choice for horns, and lights.

 

[JPSmit]

thanks for the link - that's going to be a huge help!

 

[zimmy]

standard relays are around $4 at oreillys.....z

 

[dklawson]

$4 isn't a bad price for the relays. However, depending on how much it costs to ship them to Canada, bgmicro.com may save you some money. The relays cost $2 from bgmicro and they sell pre-wired sockets for them for $1.40

The nice thing about using the ISO/Bosch relays (regardless of where you buy them) is that they are universally available.

 

[Jim_Gruber]

The Daniel Stern Link I posted references Bosch Relays and the little numbers on the link correspond to the ways the posts / wires on the relays are numbered.

This isn't rocket science, to hook up. Take a look at one of the headlight relay diagrams they all are essentially doing the same thing. Once you figure out that you are interupting the current flow to the headlights so that it comes direct or as close as possible to direct from the battery instead of through a 40-50 y.o. wiring and green with corrosion multiple points of failure switch all of a sudden the light bulb will come on and you will understand.

 

[JPSmit]

all of a sudden the light bulb will come on and you will understand.

figuratively and literally I presume

 

[Jim_Gruber]

You've got it!!!!!!!!

 

[regularman]

I would recommend the bosch type relays. They are readily available and easy to replace. Its the little 1"x1" black box with 4 prongs on it.

 

[JohnDough]

Just a caution.

In most instances one will connect the original power wire, i.e. from the headlight, horn etc to point 86 of the relay and then point 85 to earth. Then for the secondary circuit you should provide a fused 12v wire to point 30 of the relay and then connect point 87 to the headlight etc.

However on the sprite you should connect the original horn wires to point 86 and point 85 , reason being that if the horn wire is shorted to earth via the relay (as per normal config) you either have it on the whole time or off the whole time already and it won't work. remember the horn button shorts the circuit to earth

As far as the standard relays are concerned , I have picked up some Hella relays which had a different layout to the ones I've used . kept blowing fuses and had me confused for a while.

 

[JPSmit]

is this just Sprites? Positive ground?

 

[Guest]

I got mine locally via Parts Express in Dayton. I think www.partsexpress.com. Relays and Mounting Sockets

I also had some from Parts Express- I would not recommend using them in any environment where moisture is introduced or may be present. The casings of these relays are not sealed. I had one of these on an electric fan and had the fan go out in a storm. The whole relay was full of water.

It's really hard to find a good relay anymore since Delco/Delphi sources their relays out from third world. Also I've seen Delco replacements that were just as badly made as the parts express one- the cases are not sealed. Your friendly neighborhood (insert your favorite corporate auto parts store that specializes in third world parts) sell these. I found some NOS Delco's on Ebay that are sealed.

 

[dklawson]

John-Peter, the relays are not unique to one ground configuration. Remember, they are only electrically actuated switches. Any of the wiring diagrams referenced above will work for a positive or negative ground car.

Gmichael52 is also correct that the ISO/Bosch relays are not sealed. However, you can usually find a place to mount them that is somewhat protected. Directly behind the grille would be a poor choice. A coworker of mine who takes Jeeps rock-crawling went so far as to build a plastic enclosure box for his relay panel to keep water out when he goes off-road.