Zetor 3011 problems

[Gulli]

Not sure this is in the right place mods feel free to move it.

The junction box on my 3011 has blown up and I have been given a new one which I'm told will fit. ( no part number on the old one naturally!) But when I fit it and reconnect the battery it blows a fuse.
Any thoughts?
Is it as simple as having the wrong box? Or is it likely to be a wiring problem?

 

[Mursal]

What junction box is it?
Is it the one for the front lights?
A fuse blowing usually signifies a short, where the battery positive (feed) is somehow connecting to the body work?
Just disconnect one wire at a time reconnecting the fuse each time to see if it still blows.
Might be best to use a few strands of wire instead of a fuse unless you have a big box full
The only other time a fuse will blow, if its to small for the load (bulb, motor etc) connected to the circuit?
Don't use to big a fuse, or the loom will be in danger of melting.
If you think a picture might help, upload one or two ......................

 

[Vincent]

Use a bulb instead of a fuse or piece of wire and them start to disconnect when bulb goes out you have found tour short

 

[Gulli]

It's the junction box for the alternator. Only 4 wires on it and wired the same way as the old box was. Tried swapping wires over but the fuse (16amp) still blows.
Will have a look for a short thanks.

 

[Mursal]

Maybe the voltage regulator?

Bigger image click

 

[Gulli]

Something like that I think. Didn't get back to it this afternoon.
Had a chat with a couple of people and going to try a different part, think we probably have the wrong box. Its like the whole system goes live when you connect the battery, even with the key out.
Fecking thing
Ironically the battery not charging is the least of its problems but the most time consuming. I think k one day it will just collapse in the yard from exhaustion

 

[Mursal]

Yes it may well have power all the time regardless of the key.
OK, shout if you want a hand sorting the charging out. To be honest those external regulators aren't the best, to much external wires running hear there and everywhere. But if you connect the wrong sort of regulator you can blow the box and from memory they aren't cheap? You will have to look at the wires on the back of the alternator and work back to the regulator. but keep in mind the alternator might not be charging anyway?
As far as I remember you apply 12Volts to the +F terminal on the alternator to get it charging. It should have a constant earth. The regulator switches the supply off when the battery reaches 14.5Volts to stop the battery overcharging. This is completely opposite to most alternators. Most regulate the voltage by switching the earth on and off, not the supply. So th correct box is important.
If you want, go to your local car breaker and get a secondhand alternator with everything in the back (built in regulator) just get the belts to match. Mount it and connect to battery and away you go. And a little wire for the charging light, that's it.
Two wires ..............

Leave the battery disconnected until you get sorted, especially if you have it in the shed with anything expensive ..............

 

[Gulli]

Thanks @Mursal appreciate the info

Alternator works fine already had that off and got it fixed. Have just put the old regulator back on for now. Battery hasn't charged off the tractor for the last 2/3 years just stick a charger on it overnight every few days or give it a pull. Just a pain
I'll have another go at it when I get a spare five minutes

 

[Dorset Lad]

The reg is for use with the original dynamo, there is no need to use it if you are using an alternator as they have a built in reg. The wiring is very simple for an alternator too which means you could chuck that sh!t reg in the scrap!

 

[Mursal]

Some of the Zetor's had an alternator with external regulator, just to be different ...............

@Dorset Lad