Captain Posted July 31, 2015 Report Share Posted July 31, 2015 Has anyone got any experience of making up their own wiring loom? I have just taken an original out of my 1973 GT6 Mk3 (which is undergoing a complete restoration) and I'm considering making a copy of it myself. I've done this with motorbike wiring looms before but the GT6 is much bigger, however the principle must be the same? I was wondering is it worth it and how easy is it to do? Can you get hold of all the right connectors / fittings etc Link to comment Share on other sites More sharing options...
Colin Lindsay Posted July 31, 2015 Report Share Posted July 31, 2015 Yes, everything available and you can upgrade connectors to take more modern components e.g. bulbs. I’ve replaced single wires that were burnt out so an entire loom should be the same principle. Link to comment Share on other sites More sharing options...
Pete Lewis Posted July 31, 2015 Report Share Posted July 31, 2015 may help to use a long board to make up a 'jig' with pins and markers to string out the fly leads and break out postions Pete Link to comment Share on other sites More sharing options...
dougbgt6 Posted July 31, 2015 Report Share Posted July 31, 2015 Yes, what Colin and Pete said. However, you might also like to consider the short comings of the loom. There aren't enough fuses and some things aren't fused at all! GT6 headlights aren't fused and all the current for them goes through the light switch. Inevitable, with that level of current, the switch contacts will corrode and become resistive. Then you get heat, sparks, and the least of your problems, dim headlights.Triumph wouldn't get away with manufacturing something as dangerous as that in todays world. A common mod is to split up the circuits and install additional fuses and relays for everything. I would go for that rather than copying the original. Link to comment Share on other sites More sharing options...
Dick Twitchen Posted July 31, 2015 Report Share Posted July 31, 2015 This is exactly what I did when I restored my GT6 Mk1, although I did not slavishly follow the original in producing it. A bank of relays and a modern fuzebox, on an ally plate, sits on the the bulkhead where the passenger glove shelf is and I used modern thinwall cable throughout where appropriate. I also used 7 core trailer cable as the main bearer from fwd to aft by the passenger sill along with copious amount of shrink wrap to keep everything tidy. Vehicle Wiring Products were my chosen supplier for everything; they used to have a catalogue (probably now a website) with useful supporting documentation on relay fittings etc. Comments are usually along the lines of, when the bonnet is up of 'where is the fusebox?' and 'why is the engine bulkhead not full of cabling'. How much of originality in that sense, like beauty, is in the eye of the beholder. Dick Link to comment Share on other sites More sharing options...
Captain Posted July 31, 2015 Author Report Share Posted July 31, 2015 Colin, Pete, Doug and Dick, Thanks for the advice and encouragement! I've never modified any wiring before but I can copy an existing loom or follow a schematic diagram. I'd like to add the extra fuses as Doug and Dick have suggested but not sure how this should be done. Any advice or diagrams would be greatly received. I found this site on the net .http://www.mygt6.com/site/wp-content/uploads/2011/06/GT6MkIIIwiring.jpg Would this be good to follow or should I use the one in the Triumph workshop manual page 6.502? Andy Link to comment Share on other sites More sharing options...
dougbgt6 Posted July 31, 2015 Report Share Posted July 31, 2015 Yes I've got that one! So much easier to read in colour. I've also got one of these: http://www.ebay.co.uk/itm/H4-9003-Headlight-Booster-Wire-Harness-Connector-Relay-Fuse-Socket-/390938014554?hash=item5b05b8b35a Don't know how they do it for the money but it's reasonable quality. The battery connection has to be extended and on mine, I've had to remove and reconnect the headlamp connectors once I'd fed the cable into the headlamp cowl. Here's a guy who's fitted relays to a Spitfire. http://williamcolumbine.blogspot.co.uk/2010/09/headlight-relays.html Link to comment Share on other sites More sharing options...
Captain Posted August 1, 2015 Author Report Share Posted August 1, 2015 Thanks Doug, Great blog from Will Columbus. I'm very clear now about what to do. What other circuits would you suggest fitting with fuses and relays (if any)? Andy Link to comment Share on other sites More sharing options...
Pete Lewis Posted August 1, 2015 Report Share Posted August 1, 2015 and for a catalogue to browse for al sorts of good ideas and things to dream about car builders solutions http://www.carbuildersolutions.com/uk/ amongst many others Pete Link to comment Share on other sites More sharing options...
dougbgt6 Posted August 1, 2015 Report Share Posted August 1, 2015 Well, I'm only just in front of you changing the wiring but, looking at the coloured wiring diagram there are 9 circuits (counting wiper switch and motor as one) hanging of 3 fuses. And even with the additional headlamp loom there is still an unfused wire to the light switch. So I'd split all those up. I'm not sure if other relays are required, I suppose the heated rear screen draws a lot of current,( if it ever worked ). I'm sure others have some experience to share who've completed the job. Link to comment Share on other sites More sharing options...
dougbgt6 Posted August 1, 2015 Report Share Posted August 1, 2015 And the live feed to the ignition switch is unfused. Link to comment Share on other sites More sharing options...
John Bonnett Posted August 1, 2015 Report Share Posted August 1, 2015 Just in case it might be of interest, I have drawn out the circuit diagram that I designed for my GT4 and I'd be pleased to let any member have a copy. All the higher consumption circuits are relayed and each circuit protected by appropriately rated fuses. In all, there are nine relays and twenty three fuses. It all works fine and I'd be more than happy to share it with you. Link to comment Share on other sites More sharing options...
dougbgt6 Posted August 1, 2015 Report Share Posted August 1, 2015 John, Wow! I would LOVE to see that! Is it easy to put on the inter web? Doug Link to comment Share on other sites More sharing options...
Pete Lewis Posted August 2, 2015 Report Share Posted August 2, 2015 Ive got a box full of re -setable blade fuses if theyre any use , just press to reset. as an industry std. ignition was rarely fused Pete Link to comment Share on other sites More sharing options...
John Bonnett Posted August 2, 2015 Report Share Posted August 2, 2015 John, Wow! I would LOVE to see that! Is it easy to put on the inter web? Doug I can send you a copy Doug with pleasure. Link to comment Share on other sites More sharing options...
dougbgt6 Posted August 2, 2015 Report Share Posted August 2, 2015 Thanks John, Can it be sent over the internet? Doug Link to comment Share on other sites More sharing options...
John Bonnett Posted August 2, 2015 Report Share Posted August 2, 2015 Thanks John, Can it be sent over the internet? Doug PM sent Doug Link to comment Share on other sites More sharing options...
bluelighttaxidriver Posted August 2, 2015 Report Share Posted August 2, 2015 Just in case it might be of interest, I have drawn out the circuit diagram that I designed for my GT4 and I'd be pleased to let any member have a copy. All the higher consumption circuits are relayed and each circuit protected by appropriately rated fuses. In all, there are nine relays and twenty three fuses. It all works fine and I'd be more than happy to share it with you. Would love to get my hands on this too..! A little way off wiring still, but I've been thinking about the limitations of the original loom too... 2 Link to comment Share on other sites More sharing options...
John Bonnett Posted August 2, 2015 Report Share Posted August 2, 2015 Would love to get my hands on this too..! A little way off wiring still, but I've been thinking about the limitations of the original loom too... PM sent Link to comment Share on other sites More sharing options...
gt6chris Posted August 3, 2015 Report Share Posted August 3, 2015 One of the nicer blade fuse boxes out here is this one supplied by Autosparks: http://www.autosparks.co.uk/product_info.php?products_id=1273 I think John has used these with great success also. It allows you to easily split the circuits into several smaller circuits and fuse accordingly. I used this on my GT6. I retained the original loom but stripped it back and added bits where needed. I added relays for the headlights, electric fan (never fitted but the wiring is there if needed) and front driving lights. These were fed from a secondary fuse box so that all the switch gear was low current only. I have since sold my GT6 and have just purchased TR6. The headlights are the same type as my GT6 had but because they are still fed from the original switchgear they are pretty poor compared with the relay fed units on my old car. I have also noticed the Kenlowe fan is directly attached to the wiring without a relay and the crimped connectors are discoloured from heat. The PI fuel pump draws around 10a and is directly fed from the ignition switch. I used a proper crimp tool and soldered the joints after crimping on the GT6. I will modify high power circuits with relays on this car too. Chris 1 Link to comment Share on other sites More sharing options...
Captain Posted August 4, 2015 Author Report Share Posted August 4, 2015 Thanks to everyone who has contributed to this thread. I've learnt so much from you all and I guess many others who read it will have done too. Andy Link to comment Share on other sites More sharing options...
Alan C Posted August 6, 2015 Report Share Posted August 6, 2015 Andy I've just upgraded my GT6 with a 16 way fusebox. In hindsight a 20 way would have been ideal. Like John I've amended the standard wiring diagram to show where all the new fuses go. I'll post links to them when I get back from holiday. I used soldered bullet connections throughout and cheated with the wiring by using an old TR loom to maintain the correct colour coding. Splitting the circuits up fully will require some contorsionism behind the dashboard if you are going to attempt this with the loom in situ Splitting the green (ignition controlled) and red(secondary lighting) circuits,requires sticking the soldering bolt deep inside the dash. With care it can be done. There's no way you'll get a crimping tool into the space. Finally the quality of glass fuses is suspect to say the least. Much better with the modern blade fuses. Good luck, it's well worth the effort. Cheers Alan 1 Link to comment Share on other sites More sharing options...
John Bonnett Posted August 6, 2015 Report Share Posted August 6, 2015 Andy I've just upgraded my GT6 with a 16 way fusebox. In hindsight a 20 way would have been ideal. Like John I've amended the standard wiring diagram to show where all the new fuses go. I'll post links to them when I get back from holiday. I used soldered bullet connections throughout and cheated with the wiring by using an old TR loom to maintain the correct colour coding. Splitting the circuits up fully will require some contorsionism behind the dashboard if you are going to attempt this with the loom in situ Splitting the green (ignition controlled) and red(secondary lighting) circuits,requires sticking the soldering bolt deep inside the dash. With care it can be done. There's no way you'll get a crimping tool into the space. Finally the quality of glass fuses is suspect to say the least. Much better with the modern blade fuses. Good luck, it's well worth the effort. Cheers Alan I totally agree Alan, it is well worth doing on all levels. Once the wires to the original fusebox are disconnected it's an easy matter to remove the under dash loom by separating the plug and socket connector (to the rear loom) and work on it on the bench. This makes the job a whole lot easier than try to work under the dash. Link to comment Share on other sites More sharing options...
Alan C Posted August 7, 2015 Report Share Posted August 7, 2015 John Why didn't. I I think of disconnecting the multiplug! I was soldering all around it. Oh well you can't be bright all of the time. Alan Link to comment Share on other sites More sharing options...
John Bonnett Posted August 7, 2015 Report Share Posted August 7, 2015 John Why didn't. I I think of disconnecting the multiplug! I was soldering all around it. Oh well you can't be bright all of the time. Alan Hindsight's a wonderful thing Alan and there's always a smartarse there to rub it in. Sorry Link to comment Share on other sites More sharing options...
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