New Wiring Harness

[vette]

I have to make a decision about the new wiring going into my car and I would like to ask for your opinions. My car is not completely stock and most changes are for the interest of long term durability, enhanced options (sterio & fog lights) and ease of maintenance. So hence I am modifying the electrical system as well. I will have an alternator, and a negative ground system along with twin fuel pumps and a throwover switch for them. But here is my latest consideration:
Many years ago i eliminated the Overdrive throttle switch and have been engaging my OD directly off of the dash toggle switch. It is kind of fun to drop it down right at the flip of the switch and also shift it up the same way. No messing with the throttle switch adjustments anymore.
I also have had a desire to have a better fuse box with many circuits having their own fuse and room for more accessories. Today I started to install the new wiring harness and then had to continplate where to put the new fuse box. I thought about under the dash near the drivers side but then felt that there was no convenient place there for it. Then i realized that I'm not using the throttle switch, so why would I need to keep the O.D. relay as well. On my BJ7 the fuse box, OD relay and throttle switch all reside on the engine side firewall, drivers side, approx directly above the throttle/carb linkage. If I eliminated the old fuse box, the relay, and the throttle switch I would have enough room on the firewall to put in a decent sized fuse box with the more modern spade blade fuses. Without the throttle sw, and relay, the white/purple wire from the OD dash switch can go directly to the white green wire of the transmission 3rd & 4th gear shifter switch. Does that make any sense, and do you see any downside to this. I think some might believe that I am cannibalizing the car. But I havn't had the OD relay or throttle sw in the circuit for years anyway, why keep them hanging on the firewall and it will eliminate one or two items that could fail during a road trip. Also I wouldn't be cutting up the harness, originality could easily be restored with the addition of the removed components. Am I forgetting something, I think it will work. What you say? Dave C.

 

[Bob_Spidell]

I think you need the O/D relay for the same reason the O/D relay was installed in the first place: to use a small current from the panel switch to switch a larger current through the relay to the solenoid. In my experience the panel switches are somewhat fragile to begin with and removing the relay would only make them more so. I've replaced a couple panel switches, but the relay on my BJ8 lasted about 150K miles and when it started to fail--on the road in Canada--I opened it up and filed the points and it held up for several thousand more miles before I replaced it. I don't know the rating of the switch but if it could handle the load Austin wouldn't have 'wasted' the pound or two it cost to install a relay. The fact your switch has lasted surprises me--how many miles a year do you drive?

I rather like the throttle switch, too. You can throw the switch when you're coasting, then when you get on the accelerator you get an automatic 'kick down' gear. Very high tech. Once set properly they don't seem to be much problem, either; IIRC I opened mine up once and cleaned up the points and adjusted per the manual and it's been flawless for 170K+ miles.

 

[Patrick67BJ8]

I have to make a decision about the new wiring going into my car and I would like to ask for your opinions. My car is not completely stock and most changes are for the interest of long term durability, enhanced options (sterio & fog lights) and ease of maintenance. So hence I am modifying the electrical system as well. I will have an alternator, and a negative ground system along with twin fuel pumps and a throwover switch for them. But here is my latest consideration:
Many years ago i eliminated the Overdrive throttle switch and have been engaging my OD directly off of the dash toggle switch. It is kind of fun to drop it down right at the flip of the switch and also shift it up the same way. No messing with the throttle switch adjustments anymore.
I also have had a desire to have a better fuse box with many circuits having their own fuse and room for more accessories. Today I started to install the new wiring harness and then had to continplate where to put the new fuse box. I thought about under the dash near the drivers side but then felt that there was no convenient place there for it. Then i realized that I'm not using the throttle switch, so why would I need to keep the O.D. relay as well. On my BJ7 the fuse box, OD relay and throttle switch all reside on the engine side firewall, drivers side, approx directly above the throttle/carb linkage. If I eliminated the old fuse box, the relay, and the throttle switch I would have enough room on the firewall to put in a decent sized fuse box with the more modern spade blade fuses. Without the throttle sw, and relay, the white/purple wire from the OD dash switch can go directly to the white green wire of the transmission 3rd & 4th gear shifter switch. Does that make any sense, and do you see any downside to this. I think some might believe that I am cannibalizing the car. But I havn't had the OD relay or throttle sw in the circuit for years anyway, why keep them hanging on the firewall and it will eliminate one or two items that could fail during a road trip. Also I wouldn't be cutting up the harness, originality could easily be restored with the addition of the removed components. Am I forgetting something, I think it will work. What you say? Dave C.

Go to John Simms website for Fuse Blocks, www.healey6.com . Charlie Hart on Calif. has made Fuse Blocks for 7 fuses. He has just sent me one for BJ8's which is new and I'll be testing. BJ7 and BJ8's are very different wiring for the Fuse Block area. Green wire hookup's are opposite sides.

 

[British_Recovery]

Go see what Advance Auto Wire has available. www.advanceautowire.comBob

 

[steveg]

Go to John Simms website for Fuse Blocks, www.healey6.com . Charlie Hart on Calif. has made Fuse Blocks for 7 fuses. He has just sent me one for BJ8's which is new and I'll be testing. BJ7 and BJ8's are very different wiring for the Fuse Block area. Green wire hookup's are opposite sides.

Charlie's email: hartcg@msn.com
I'm using one if his non-BJ8 versions.

 

[57_BN4]

Dave- as you have identified, the OD relay functions as a latch (with the throttle switch) to protect the OD clutch from disengagement under hard engine braking and also as a relay to protect the dash switch from the 30-odd amp current that the solenoid draws at pull-in. There are two windings in the OD solenoid, a high current one to pull it in and a low current one to hold it in plus a set of contacts to open the high current coil once it is pulled in.

If you remove the OD relay then your dash switch might fail at some time but I'd reckon if you use a more modern switch you'd get a fair amount of use out of it between fails. The high current is only for a few milliseconds then it goes to about one amp.

Andy.

 

[vette]

Andy, Bob and All,
I am very sorry that my most recent post to this thread was materially in error. So I have deleted it. Just after I posted it and read Andy's response, I did some more digging which is what I should have done to begin with. I found some of my older material and relized my memory of the circuit was totally wrong. Bob is very much correct in gaurding me against removing the OD relay. I realized that I had removed the throttle switch but the relay was still in operation. I think! that is probably why my dash switch has not given out on me after 7 or more years of about 2000 miles a year. Thanks again everyone for your advice & help. Dave C.