Nose cone wiring tidy up
Posted: Wed Oct 02, 2019 5:03 pm
Hi
I'm going through the nose cone putting relays on all the high current devices - horn, main beam, dip, fog, cooling fan. I had previously put relays on the lights but wasn't happy with having them situated deep in the nose, inaccessible unless the grille is removed, and a bit tricky to reach even then. Also, concerned about corrosion in the connectors.
I've decided to place them where the horn relay is, swapping out the fat Lucas relay and moving the solenoid valve to a better spot on the radiator mount. I can just about fit all five fused relays there. The wiring scheme is simple - use the original switched feeds as relay triggers and lay new ground and +12v direct from the battery terminal on the starter terminal to the hot side of each of the relays, but there is a problem. I do not want a connector with five wires branching out to feed the relays as it looks a bit crap and it's unreliable, so thought some sort of bus bar would do the trick.
Checking eBay turned up some candidates but they were all a bit expensive, so I decided to make my own from a scrap of metal.
I do love my tap & die set. Cannot imagine how I managed before I bought it.
I made another bar for the grounds and fitted them to the bracket that prevents intake air getting round the radiator.
The +12v bar is at the top and will have an insulating shroud to protect it from accidental shorts (eventually). I'm hoping the tails from the relay connectors can be screwed directly onto the bars; this will give a neat, professional appearance.
I bought some interesting connectors for joining the relays to the loom. They are crimp type but have heat shrink sleeves and on heating will give a waterproof seal. You can see some of them in this picture:
The loom has been opened right up from the branch that goes to the old horn relay to the nearside fog lamp. This allowed me to route the power lines to the relays without splicing more wire and having more points of failure. When it is finalised, I will rewrap the loom in non adhesive PVC loom tape and it will look original, apart from the modern relays. A price I'm willing to pay for safety and better electrical performance / reliability.
Come to think of it, I could fit a cover over the relays to hide them. Would be a good idea to help reduce corrosion, but I'm not sure what to make it from. Fibreglass I suppose, using an appropriately shaped and modified margarine container as a former.
Now some questions.. What is the anticipated amperage for each of the items being powered? I can calculate the lights (55W/12v=4.6A per lamp so 10A minimum for both, and the fogs are likely the same) but what about the air horn and radiator fan? I need to put a fuse in the feed wire next to the starter relay, and I need to use wire that is fat enough to carry the full load.
I'm going through the nose cone putting relays on all the high current devices - horn, main beam, dip, fog, cooling fan. I had previously put relays on the lights but wasn't happy with having them situated deep in the nose, inaccessible unless the grille is removed, and a bit tricky to reach even then. Also, concerned about corrosion in the connectors.
I've decided to place them where the horn relay is, swapping out the fat Lucas relay and moving the solenoid valve to a better spot on the radiator mount. I can just about fit all five fused relays there. The wiring scheme is simple - use the original switched feeds as relay triggers and lay new ground and +12v direct from the battery terminal on the starter terminal to the hot side of each of the relays, but there is a problem. I do not want a connector with five wires branching out to feed the relays as it looks a bit crap and it's unreliable, so thought some sort of bus bar would do the trick.
Checking eBay turned up some candidates but they were all a bit expensive, so I decided to make my own from a scrap of metal.
I do love my tap & die set. Cannot imagine how I managed before I bought it.
I made another bar for the grounds and fitted them to the bracket that prevents intake air getting round the radiator.
The +12v bar is at the top and will have an insulating shroud to protect it from accidental shorts (eventually). I'm hoping the tails from the relay connectors can be screwed directly onto the bars; this will give a neat, professional appearance.
I bought some interesting connectors for joining the relays to the loom. They are crimp type but have heat shrink sleeves and on heating will give a waterproof seal. You can see some of them in this picture:
The loom has been opened right up from the branch that goes to the old horn relay to the nearside fog lamp. This allowed me to route the power lines to the relays without splicing more wire and having more points of failure. When it is finalised, I will rewrap the loom in non adhesive PVC loom tape and it will look original, apart from the modern relays. A price I'm willing to pay for safety and better electrical performance / reliability.
Come to think of it, I could fit a cover over the relays to hide them. Would be a good idea to help reduce corrosion, but I'm not sure what to make it from. Fibreglass I suppose, using an appropriately shaped and modified margarine container as a former.
Now some questions.. What is the anticipated amperage for each of the items being powered? I can calculate the lights (55W/12v=4.6A per lamp so 10A minimum for both, and the fogs are likely the same) but what about the air horn and radiator fan? I need to put a fuse in the feed wire next to the starter relay, and I need to use wire that is fat enough to carry the full load.