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312-8 Ignition Wiring - Amateur Fix

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Howdy Folks,

 

I am hoping one of you knowledgeable lot will be able to help me out. I am fixing, as a surprise for my father, the ignition (that he took apart initially!) on our Wheel Horse 312-8. As we are in the UK we have struggled to get the ignition and loom which would have made this slightly easier. as the previous loom had melted slightly and a few wires came 'melted together'. And it is here where my problem lies. I have managed to get an ignition from a reputable provider here in the UK, but failed to get the loom. After visiting various local dealers they recommended I just connect the wires using spade connectors. 

From images of the ignition prior, I have been able to connect most of the wires into the new ignition with ease however where some of the wires were twisted and burned together I am struggling to work out which wires go to the remaining terminals. I have found various manuals (most helpful one attached) and think I have followed them well. However I am left over with a small red wire of which I am unsure as to where it goes.

The three wires I was left with were: a white wire, a large red wire, and a small red wire. I know that the small red one but join either the big red or the white but I am unsure.

What I would have ideally is someone being able to send across a photo to ensure that I can't get this wrong or to be able to say definitively where it joins. Furthermore if you can see any basic errors you feel I may have made an help on that would be graciously accepted. 

This is my first post but as I try to fix more and more parts it certainly won't be my last!

Hope you can help gang!

 

B

 

***This is all the info I have on the mower:

Toro 312 - 8 Cast Iron Kohler 12 HP Engine

42" side discharge

Manufactured circa 88/89

 

Vin/Model No: 78346

Serial Number: 3900161

Parts & Service Manual - E1 12K802/ R1-12 K01 8 Speed ***

 

 

1.jpg

2.jpg

3.jpg

4.jpg

Before.jpg

wheelhorsewiring.gif

Edited by WingfieldWheelHorse

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:WRS:

Can you provide the actual ID number of the 312-8? Different years had different wiring. The correct wiring diagram can then be provided for you. It appears as though you have a magneto type switch as it has a grounding lug (black wires). Wrong switches wired incorrectly can kill a magneto. 

So, please let us know the ID or at least the model year.

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***This is all the info I have on the mower:

Toro 312 - 8 Cast Iron Kohler 12 HP Engine

42" side discharge

Manufactured circa 88/89

 

Vin/Model No: 78346

Serial Number: 3900161

Parts & Service Manual - E1 12K802/ R1-12 K01 8 Speed ***

 

I have updated this on my initial post also.

Thanks for the speedy reply!

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The number should appear as for example 21-12K801 (1985) 21-12K802 (1986) etc.

However, if it was made in Europe, the numbers may be diferent.

 

Are you sure that the E1 is not a 21?

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:WRS:        Not sure what year you have, but this guide had it all. Download the guide, find your year 312 and go to that page and find each circuit.

 

 

Edited by 953 nut
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I'd try this diagram rather than the one you are using. But you have to know whether or not you have a battery ignition or magneto. This is for Battery Ignition.

 

image.png.3b740d1f0da2f0d5b16910314c385382.png

Edited by rmaynard
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The 312 414 diagram Bob posted shows battery ignition which will not be correct with the ground wires on the side of the switch indicating you have magneto ignition.

This one may be a closer guess.

The tractor identification decal was most often on the rear fender pan below the left side of the seat.

Just click on the photos below to get to the index pages. You can download the files from there.

 

The 78346 model number you posted is for the mower deck.

Garry

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Hey all, thanks for all your help.

Here is where I am at now. The only problem I have now is still working out which of my remaining three wires goes where. They were all tangled around the 2 remaining circled connections.  I believe (correct me if I am wrong) that I need to put the white by itself onto B. Then connect the think and thin red onto A.

I have attached images of the old ignition (burnt to a crisp but was still working previously) and drawn in the original wire connections. I have written in the colours of the wires and on the new ignition the letters on the connectors.

 

I have looked over both diagrams you have all send over and this is the conclusion I have come to. However I am a novice so may be complete incorrect.

 

B

Image 1 - New Connector with Coloured Wire notations and Connector labels (Purple) - Remaining connectors circled in pink,

Image 2 - Old Connector with former connections labelled. Remaining connectors circled in pink.

Image 3 - Old wire loom with the 3 melted wires over 2 connection points circled

 

New - Labelled.jpg

Old - Labelled.jpg

Before.jpg

Edited by WingfieldWheelHorse

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This diagram better matches your wire colors looking at the last photo.

G terminal  black is correct for the ground

S terminal tan is correct  for the starter circuit

R terminal pink in 3rd photo is correct (this feeds the headlamps) Red wire is wrong.

B terminal should be red from the battery

M terminal should be dark blue to the engine magneto - To be safe leave this wire off the switch until you get it running. If everything is OK hook it up. With the wire off the engine should not shut off with the key. Ground the blue wire to the chassis to shut it off or choke the carb. Blue wire in 3rd photo looks correct.

A terminal should be white to the voltage regulator

 

Hard to tell the pink from the red and tan from the white.

 

Garry

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Hi Garry,

 

so the one i have labelled red and is already connected is the pink - Thanks for clearing up.

 

B Terminal -Red from the battery should that be both remaining red wires- as if not I still have the smaller red wire not connected to anything.

 

Thanks

 

B

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28 minutes ago, WingfieldWheelHorse said:

B Terminal -Red from the battery should that be both remaining red wires- as if not I still have the smaller red wire not connected to anything

 

Yes both red go together. They have joined them at the ignition switch for convenience. If you look at the wiring diagram they show them joined just before the switch and after the fuse. Same thing.

When wires cross each other in the illustrations they pass each other. When you see a black dot it means they are joined.

 

Garry

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Thank you everyone. It was a simple thing and what I believed in the end but as it was my first go at this I am glad I consulted you all. 

 

Now to get started on the loose choke cable and throttle!

 

While you are all here, does anywhere know where you can get decal designs to replace old ones that faded etc. Even if you can get pdfs of them etc.

 

success!.jpg

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:text-coolphotos:     There is a European Vendor making reproduction decals but I couldn't find it now. Perhaps @meadowfield or another Euro member will come along to help. Here in the states we have http://www.redoyourhorse.com/ and he may be able to ship.

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16 hours ago, 953 nut said:

:text-coolphotos:     There is a European Vendor making reproduction decals but I couldn't find it now. Perhaps @meadowfield or another Euro member will come along to help. Here in the states we have http://www.redoyourhorse.com/ and he may be able to ship.

 

that euro vendor is me....

 

restorationdecals.co.uk :D

 

 

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