- Location
- north Wales
Is it quite straightforward to replace a dynamo (currently giving out 9volts) with an alternator on a ford4000 ? It stops and starts a lot and I could then put more lights on it too!
Alternator instead of dynamo
- Thread starter ford4000
- Start date
Exfarmer
Member
- Location
- Bury St Edmunds
Its very simple, you will not need the regulator.
Hopefully the tractor is negative earth. But that can be sorted.
It is very important to fit the new alternator so that the belt is lined properly and the retaining bolts do not stretch the mounting points as they will quickly fracture. Washer it up even if this mean lots of them!
Any good auto electrical place should be able to supply a suitable one and a new wiring diagram ( which is very simple)
Hopefully the tractor is negative earth. But that can be sorted.
It is very important to fit the new alternator so that the belt is lined properly and the retaining bolts do not stretch the mounting points as they will quickly fracture. Washer it up even if this mean lots of them!
Any good auto electrical place should be able to supply a suitable one and a new wiring diagram ( which is very simple)
Mursal
Member
Yes, get one with the correct belt from a breaker, or new you decide.
We usually use a Lucas like below
Get the correct side so you have two bolts at the bottom, just make the dynamo bracket carry the alternator. Checking for alignment of the belt as you go ....
Electrics:
Output wire:
Big wire from alternator output terminal to battery + positive terminal, best to go the the + terminal on the starter solenoid, just tidier.
If you have good wiring connect D and B at the regulator, does the same thing.
Warning light: Earth it through the small WL terminal on the alternator. So it lights up when not charging and looses its earth when charging/goes out.
If you have good wiring connect WL and F at the regulator, does the same thing. You need to connect F down at the alternator to the WL terminal. Disconnect the dynamo regulator ...........
Shout if your still stuck .............
We usually use a Lucas like below
Get the correct side so you have two bolts at the bottom, just make the dynamo bracket carry the alternator. Checking for alignment of the belt as you go ....
Electrics:
Output wire:
Big wire from alternator output terminal to battery + positive terminal, best to go the the + terminal on the starter solenoid, just tidier.
If you have good wiring connect D and B at the regulator, does the same thing.
Warning light: Earth it through the small WL terminal on the alternator. So it lights up when not charging and looses its earth when charging/goes out.
If you have good wiring connect WL and F at the regulator, does the same thing. You need to connect F down at the alternator to the WL terminal. Disconnect the dynamo regulator ...........
Shout if your still stuck .............
multi power
Member
- Location
- pembrokeshire
You can even get a dynamo that looks like an alternator for a 4000
- Location
- north Wales
- Location
- north Wales
Fit dynamo I meant not regulator
- Location
- Lincolnshire
Essentially all it needs is a lead to the battery to work, but you wouldn't have an ignition light so a bit more wiring is needed, IE battery to key switch then to light then to small feed terminal on alternator, the 2 big terminals are the same thing and go to battery or in practice starter solenoid.
Mursal
Member
Just disconnect the wires from the dynamo regulator. If you have good wiring and use WL, D, B and F all that will be left is the earth wire, and possible another B. But if you do your own new wiring, disconnect all wires from regulator and insulate the wires that were on B, so they cant touch the bodywork.
The alternator has its own regulator builtin.
If in doubt, post a few pictures of the wiring when you get the alternator mounted.
Don't just "chance on" with the wiring ..........
Dynamo Regulator
The alternator has its own regulator builtin.
If in doubt, post a few pictures of the wiring when you get the alternator mounted.
Don't just "chance on" with the wiring ..........
Dynamo Regulator
Last edited:
Why bother? Dynamo is quite capable of providing all the charge you will need, unless you intend to fit aircon or something. Once the tractor has started there is no electrical load, unless the lights are in use,and you would need many of those to get to 224 watts, which is the 22 amp dynamo output. Have the dynamo serviced, probably be cheaper than an alt in any case.
Dynamo used to charge fine, but we used to go though a new regulator every 6 months. IIRC there was a bit of fabrication involved in making a new bracket to fit the alternator, but other than that, not too bad.....
pattern regulators by any chance? Leyland 384 here is still on its original unit, as is my 253. LRA 101 or similar will fit straight onto dynamo brackets, just put a spacer on the rear bolt. left or right hand can be made to fit by spinning the drive end mounting plate. Beware that some alternators will NOT charge a dead flat battery.
No, genuine Ford regulators,could never get to the bottom of the problem, so did away with the lot and fitted an alternator.
MMM well ford, for their cars at least purchased eletrics from whoever was passing at the time! I remember a cortina that had a lucas starter, autolight dynamo, ducillier regulator! That was a brand new car!
One way to destroy a regulator is to leave the engine running at the speed where the warning light is flickering, that burns the points.
One way to destroy a regulator is to leave the engine running at the speed where the warning light is flickering, that burns the points.
John 1594
Member
- Location
- Cambridgeshire
cheapest fix is to put an alternator pulley on the dynamo.....we did that to the 990 12 years ago when we fitted a new 22a dynamo and box, set idle speed so it just puts the warning light out
its never been touched since, and its never had a flat battery either
And for anyone who thinks that doing so may over speed the dynamo....rubbish!!! Dynamos in cars of the time had similar sized pulleys to what the tractors did, and the car engines revved much harder, so fitting a smaller pulley to a tractor just makes it charge as fast as it would in a car
its never been touched since, and its never had a flat battery either
And for anyone who thinks that doing so may over speed the dynamo....rubbish!!! Dynamos in cars of the time had similar sized pulleys to what the tractors did, and the car engines revved much harder, so fitting a smaller pulley to a tractor just makes it charge as fast as it would in a car
John 1594
Member
- Location
- Cambridgeshire
You had a bad earth then...a bad earth will cook a regulator in a matter of seconds, we had this with a TE20 we restored....new dynamo and new box, fitted after painting....the earth wasnt quite good enough, and after half hour the resin was dripping out of the back of the red hot dynamo because the box had shorted out
- Location
- Lincolnshire
Just because a car had a dynamo and revved twice as fast does not mean the dynamo revved twice as fast, its to do with the crank pulley size!
Alternators came into fashion because they can spin very fast and give more output (notice small pulley) this is due to the heavy bit staying still and the light bit turning, the down side is the current went from direct 12v to alternating 12v, not a problem once diodes were invented.
- Location
- Lincolnshire
Back in those days everyone went on strike (epecially Lucas) and you fitted what was available.
Indeed, I well remember all the cars arriving minus headlights!
Mursal
Member
Alternator every time, apart from it looking a bit modern, well 1970's on a Ford ...............
Alternator using the warning light circuit to excite (warning light working as it should) will put out more with the engine ticking over compared to the dynamo running flat out. Just tip the revs to put the warning light out and you are charging the battery, not everyone uses new batteries in their tractors or runs old engines hard.
Alternator using the warning light circuit to excite (warning light working as it should) will put out more with the engine ticking over compared to the dynamo running flat out. Just tip the revs to put the warning light out and you are charging the battery, not everyone uses new batteries in their tractors or runs old engines hard.