Two wires left in the engine compartment

[alloriginal1owner]

Hi all,

after two years of restauration I reinstalled the engine of my Milly. Unfortunately I got two wires left and have forgotten what they are for. Can anybody help me, please? It's in that place where other Morris Minors have their fuel pump. But Milly never had an electrical pump, ist's a mechanical one directly on the engine.

[arjay]

It appears that you have a wiring loom for a car later than yours. The wires are shown here

[alloriginal1owner]

Thanks, @arjay. That's really strange. They should habe been isolated then. But I guess you are right.

[philthehill]

The Minor was not factory fitted with a mechanical fuel pump. The Minor should have an electric fuel pump.
You either have a non original engine or someone has fitted a mechanical fuel pump to overcome problems with the original SU electric fuel pump.

[alloriginal1owner]

You either have a non original engine or ...

The actual engine is not original. But I think the former one was, and that had the mechanical pump on it. I know somewhere I should find a list where I can compare numbers of engines and chassis which belong together. Is that list available on the internet?

[les]

If your former engine had a mechanical pump, that engine, in my opinion, would have come from an Austin minor van, or possibly a 950 Minor. I’m pretty sure I’m right in saying It’s the Austin 1098 engine version (or 950 Minor) that has the opening, covered by a plate, for a mechanical pump, whereas the Morris 1098 had the bossing but no opening in the casting.
Morris engine with blank pump outlet.

1FD25C4E-906E-4442-8D91-0F6422597041.jpeg (128.84 KiB) Viewed 2505 times

[alloriginal1owner]

If your former engine had a mechanical pump, that engine, in my opinion, would have come from an Austin minor van, or possibly a 950 Minor. I’m pretty sure I’m right in saying It’s the Austin 1098 engine version (or 950 Minor) that has the opening, covered by a plate, for a mechanical pump, whereas the Morris 1098 had the bossing but no opening in the casting.
Morris engine with blank pump outlet.
1FD25C4E-906E-4442-8D91-0F6422597041.jpeg

My car is from 1957 and both the "new" and the old engine are 948cc with the plate covered opening. I'd really like to know, if the former engine belongs to the chassis.

[ManyMinors]

You can get a Heritage certificate from the Gaydon museum which will tell you the original engine number but, as Phil has already pointed out, no Morris Minor left the production line with a mechanical fuel pump. Your car has been modified at some time in the past - as the original wiring clearly shows. You should check, for safety's sake, that the white wire is not "live" when the ignition is on because that is the supply to the original electric pump

[alloriginal1owner]

You can get a Heritage certificate from the Gaydon museum which will tell you the original engine number

Thanks!

You should check, for safety's sake, that the white wire is not "live" when the ignition is on because that is the supply to the original electric pump

I know. I wonder why it wasn't so yet.

[geoberni]

As already stated, that white wire should/could be live , unless disconnected at the other end where it is supposed to be a dedicated white cable from A3 on the Fuses.
I say 'supposed to be' because I have yet to work out where my car picks up the fuel pump supply, it's somehow got a yellow cable from behind the dash.... that's on my list of things to sort out one day soon.

I'm fascinated by the earth wire though, why it seems to be clamped to the choke outer sheath with an insulated P Clip....?.

pump.JPG (89.49 KiB) Viewed 2451 times

[ManyMinors]

I think that is the speedo cable actually, but that earth wire would normally be attached to one of the pump mounting screws of course. Because the pump is missing there is nowhere for the earths to attach. Of course it cannot earth anything in its current position - but it doesn't need to. It would be a shame to cut the wires off because somebody might wish to re-instate the correct pump one day?
I hate untidy wiring on a car and this could be tidied up a bit. Checking and covering that live cable is a must!

[geoberni]

I think that is the speedo cable actually, but that earth wire would normally be attached to one of the pump mounting screws of course. Because the pump is missing there is nowhere for the earths to attach. Of course it cannot earth anything in its current position - but it doesn't need to. It would be a shame to cut the wires off because somebody might wish to re-instate the correct pump one day?
I hate untidy wiring on a car and this could be tidied up a bit. Checking and covering that live cable is a must!

Of course, the Choke cable is much thinner.
So my pump is just earthed via it's case to the bodywork, no cable at all, so I've no experience is this particular aspect of Minor circuitry.
As a SII, Basil's wiper motor is inside, so I've got nothing in that area of the car except the fuel pump and the screen wash container.
Does that extra 'fly lead' usually go to the bodywork as an earth connection?
If so, it's presumably also supposed to be earthing something else on the black lead that's coming from within the car, so what isn't currently earthed?
Something isn't right......

[pgp001]

That earth connection circled in red, looks to be connected to the battery hold down hook, not exactly the best point for a good earth.

Phil P

[philthehill]

The white cable is the live feed to the fuel pump. If it is not required it should be fully insulated.
The red circled earth wire should be affixed under the head of the fuel pump mounting bolt. The mounting bolt is screwed from the inner face of the battery tray into the base of the pump.
The un-circled earth wire should be affixed to the fuel pump iron body by a small screw to provide a return earth.
The rubber pump diaphragm can insulate the iron body from the car body return earth.
The earth wire has to be connected to both the pump body and the car body to allow the pump to work satisfactory .
The black wire into the loom is a earth return. The two earth connectors if not required can be fully insulated and secured so as not to foul any thing in the immediate area.
The thick cable attached to the battery clamp by an insulated clip is the speedo cable.

[alloriginal1owner]

The white cable is the live feed to the fuel pump. If it is not required it should be fully insulated.
The red circled earth wire should be affixed under the head of the fuel pump mounting bolt. The mounting bolt is screwed from the inner face of the battery tray into the base of the pump.
The un-circled earth wire should be affixed to the fuel pump iron body by a small screw to provide a return earth.
The rubber pump diaphragm can insulate the iron body from the car body return earth.
The earth wire has to be connected to both the pump body and the car body to allow the pump to work satisfactory .
The black wire into the loom is a earth return. The two earth connectors if not required can be fully insulated and secured so as not to foul any thing in the immediate area.
The thick cable attached to the battery clamp by an insulated clip is the speedo cable.

Thanks! This is nice to know, if I might install an electric pump in the future. For now I will deinstall the connection to the battery hook and insulate the wires.

[geoberni]

So, I understand Phil's point about the possibility of the Rubber Diaphragm potentially causing the pump earth not to be that great, hence the earth cable between points A and B to the bodywork. (so I'll add that to my list of little jobs to do since Basil doesn't have one)

Random Illustration using photo from interweb.....

But, as the cable originally comes from inside the car 'C', it must be intended to earth something else as well. I would get behind the glovebox and see where it comes from. Unless anyone can shed some light on it.....

pump1.JPG (85.02 KiB) Viewed 2393 times

[philthehill]

If I remember correctly the black cable going into the loom goes inside the car to a central earth point located behind the dash.

[geoberni]

If I remember correctly the black cable going into the loom goes inside the car to a central earth point located behind the dash.

Ummm, very plausible, but slightly odd concept. Have an item that is in the engine bay right next to the battery yet go to the trouble of running an earth cable into the passenger compartment. Not particularly an efficient design concept. My pump currently runs fine with no earth cable at all, so a simple link from the top section to a main mounting bolt would alleviate any possible issue with a poor earth between the pump casing sections.
I'll have to take another look behind my glovebox liner sometime and see what I can find. I think the person who fitted the new loom to Basil in the past may have been a bit of a gash type, it's a bit of a cats cradle mess behind there.

Seems every days a school day with Minors....

Edit to add:
So having a hour to spare, I popped outside and took a look at Basil, and I now know why my Fuel Pump supply wire is yellow.
Because he's a SII that's been re-loomed to early 1000 harness (DB10 Relay sort) the section of loom that should go out to the Wiper Motor/Fuel Pump has been routed inside to the internal Wiper Motor. Both the Black earth lines are connected to the wiper motor.
The White for the fuel pump supply is then inline spliced to the Yellow to reach outside. At least it a suitable gauge cable.