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SOLVED: Fixing electrics on Morris Minor with 1275 swapped in

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jehuie

jehuie

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I need some tips on cleaning this wiring up. Someone (my late father) rewired it this way and it has worked for many years. The alternator recently stopped charging the battery and I have to make a decision on whether to try to get this mess working again....or to try to put it back to use the control box again. The original 1960 Morris minor engine has been swapped out and it now has a 1275 from what I suspect was from a Sprite.

So my questions are many but to start with:

1) Will the control box on the Morris Minor work with this newer engine/alternator if I was to try to move it back?
2) Is there a way to test that control box to see if it's still working properly? I'm assuming it was all bypassed for a reason.
3) Should I try to get it working again as it is currently wired prior to trying to restore it to the original?

I found my dad's old diagram he drew up for how he has it wired now...but it seems to be not entirely accurate:

IMG_9632.JPG


IMG_9634.JPG


IMG_9635.JPG
 
I would suggest that he probably bypassed the control box because the alternator has a regulator built in. It seems most of them now do. Anyway, they most likely will not work together. Also, the fact that it has a 1275 doesn't really matter. It is essentially still the same engine with the same electrics, just a little bigger on the inside.
 
Also converted to negative ground, likely due to alternator conversion. My take would be to keep the alternator setup.
 
I'll take a look at my Minor when I get home from work today (mine is also 1275 with alternator). As Bayless mentioned, control box is usually bypassed as the alternator has its own internal regulator. Sometimes the control boxes are gutted so that you can use them just for the connections to make things look original, but that's a cosmetic decision.

Alternator is a nice upgrade to have, so it's worth getting that sorted out. Mine was done by a previous owner, and it's been rock solid.
 
Ah....ok, that explains the reasoning because it certainly has an alternator now and it is definitely negative ground. I just remember someone posting to always put things back to original when possible for best results which makes sense to me. But in this case it sounds like that's not a good option.

The way it's wired is not reliable simply because of the way the connections are hooked up. The connectors are stacked in such a way that they fall off when the car vibrates or goes over bumps. So I need to replace that entire "fuse block" with something better.

Until recently, the battery was charging fine. I pulled the alternator and had it tested and it checked out as good. I followed the wiring up to the fuses and, sure enough, a connector (with 3 wires stacked on it) had fallen off. I plugged it back into where it should go according to that hand-written diagram but it's still not charging.

Notably, there is a loose yellow wire next to the fuse block still which has no connector and it's not clear where it is supposed to connect since it's not on the drawing as far as I can tell. It may not have been connected at all originally. But I think it goes through the firewall and to the ignition light.
 
drooartz said:
I'll take a look at my Minor when I get home from work today (mine is also 1275 with alternator). As Bayless mentioned, control box is usually bypassed as the alternator has its own internal regulator. Sometimes the control boxes are gutted so that you can use them just for the connections to make things look original, but that's a cosmetic decision.

Alternator is a nice upgrade to have, so it's worth getting that sorted out. Mine was done by a previous owner, and it's been rock solid.
Click to expand...
Thank you. This would be helpful to see how others have set this up after converting to an alternator. Especially if you happen to have wiring diagrams and/or pictures!
 
I found this drawing online of a standard Lucas alternator wiring. The connections look like what I have on my alternator but it's not wired this way exactly. Can someone explain to me why the bottom two connectors that go to the bottom of the solenoid are there? One is a solid line and the other is dashed. But it appears to me that both tabs on the solenoid are actually connected to each other at the solenoid. So...why are there two wires coming off of it going to the same location rather than just having a single wire?

altconn.png
 
Here are the pics from my Morris. The old regulator is gone (in its place is the reservoir for the hydraulic clutch conversion used with the Datsun 5-speed).

Right below the main wiring loom you can see where the wires were connected and then taped off. I'm assuming those were the ones that originally went to the regulator.

IMG_1203.jpeg


IMG_1204.jpeg


IMG_1207.jpeg
 
drooartz said:
Here are the pics from my Morris. The old regulator is gone (in its place is the reservoir for the hydraulic clutch conversion used with the Datsun 5-speed).

Right below the main wiring loom you can see where the wires were connected and then taped off. I'm assuming those were the ones that originally went to the regulator.
Click to expand...
That looks much cleaner than what is going on in mine. Thank you! And your colors are way more obvious. Mine all look faded and dirty so it's harder to tell them apart. I find it interesting that mine has an extra relay thrown in there but that I don't see that in yours at all. Mine just looks overly complicated.
 
Welp, I figured out the issue. I'm still not clear on some of my previous questions. And I still don't have the ignition light wired up since the yellow wire is just hanging free. But otherwise its all working now and the battery is charging again.

So the issue was....one end of the fuse was a little rusty so it was not making good contact with the fuse holder.

I tested the fuses right at the beginning. But I didn't check to be sure it was making good contact withe the holder.

Bought a new fuse and replaced the old one and it all started working again.

Sometimes it's the simplest things!
 
jehuie said:
Sometimes it's the simplest things!
Click to expand...
So true! Good work sussing it out and getting things working. Now when you have time you can do a bit more cleanup.

That relay could be for a number of things --- headlights, horn are common. With so few fuses there are a number of things unprotected in the stock circuit. Full headlight draw goes through the switch for instance, so that is a nice one to protect.

When I do finally get around to my Bugeye (also with a 1275 and alternator conversion) I've got some of those decisions to make and likely a fully custom wiring loom to put together.
 
drooartz said:
That relay could be for a number of things --- headlights, horn are common. With so few fuses there are a number of things unprotected in the stock circuit. Full headlight draw goes through the switch for instance, so that is a nice one to protect.
Click to expand...
Looking at that hand-drawn wiring diagram that my dad drew, it appears that the relay is there to only allow power to the alternator when the ignition is turned on. I'm not sure this is necessary since it doesn't look like it's that way in @drooartz pictures.
 
Good for you for sorting it out! Iā€™m constantly trying to figure out the spaghetti under the hood and dash on my Traveller since there are all kinds of issues. Itā€™s been altered many times by POs, the major hack was when they installed a Datsun engine and part of some Datsunā€˜s wiring loom, argh!
 
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