How to Update your Charging System

Here you can get How to Update your Charging System and Electrical working.

Alternators are powerful enough to cope with the demand for current made by a modern car’s electrics, but dynamos often aren’t . So if your car has a dynamo, and its output is inadequate, it makes sense to swap a dynamo for an alternator.

Removing the old dynamo and fitting the alternator are fairly straightforward. the main difficulty is mounting the alternator, because it’s a different size from a dynamo, and wiring it in.


Disconnect the battery , remove the generator drive belt and take out the dynamo. Wrap, in many insulating tape, the thick wire that ran to the dynamo D terminal in order that it cannot touch the bodywork.

The rear of the dynamo is mounted to the engine block via a right-angled bracket, one end of which bolts to the block, the other end to a mounting point on the rear casing of the dynamo. Look to see if there’s a second mounting point on the block just forward of the existing one. If there’s , you’ll simply unbolt the mounting bracket from the block, move it forward and bolt it into the new mounting point. you’ll then mount the alternator in situ.

If there’s no second mounting point, you’ve got two choices. The easier option is to buy a special, extra-long mounting bracket, bolt this to the engine block in situ of the old bracket, then mount the alternator thereto. But these brackets aren’t available for all cars, in which case the choice is to adapt the prevailing mounting point to require the alternator.

Simple mounting

If there’s a second mounting point on the engine block, or if you’ll buy and fit a conversion bracket, offer the alternator to its mounting points. It should fit snugly, but you’ll find that the rear mounting point on the alternator doesn’t butt up to the bracket on the block. If so, you would like to regulate the alternator’s rear mounting. Find the short metal tube on the mounting and use alittle hammer to softly knock this tube forwards or backwards until it just touches the mounting bracket. Now bolt the alternator in situ.

Use a ruler to see that the pulley is in line with the crankshaft and water pump pulleys. If it is not , you’ll need to place washers between the alternator and its front bracket until it’s level.

Existing mountings

If you have to use the existing dynamo mounting point, first bolt the alternator to its front mounting point. Check the alignment of the alternator pulley (see above). Now tap the tube on the rear mounting as far through the bracket as it will go. If it doesn’t reach the rear mounting on the engine, cut a length of metal tube to run between the top of the tube and the bracket on the engine.

Fit an extended bolt through the rear bracket on the engine and pass it through the piece of tube you narrow . Push it through the rear mounting point on the alternator, then fit a washer and nut thereto – leave the nut loose for now.

Electrical work

Fit an eye connection to one end of your cable and a multi-connector plug to the other end. Then attach the eye end to the starter solenoid or battery live terminal and therefore the other end to the ± terminal on the alternator.

Attach the small terminal that fitted to the dynamo F terminal to the alternator IND terminal using the multi-plug. At the voltage regulator , disconnect the F and WL wires and join them together. The full wiring diagram , with cable sizes, is shown.


Attach the slotted adjuster strap to the alternator and to its mounting point on the engine. make sure that the alternator pivots freely. You may find that you simply need to bend the slotted strap to form it fit. If that doesn’t work you’ll got to buy the right strap for the alternator. Fit a new generator drive belt and tension it correctly.

Wiring up

The alternator must be connected to the ignition red light and to either the input terminal on the starter solenoid or the live battery terminal. Using 97/.012 (97/.30) cable, measure how much you would like and cut it to length. Attach a suitable connector to every end of the cable, and connect it to at least one of the large terminals within the rear of the alternator marked + (it doesn’t matter which one).

Run the cable to your chosen live point following the wiring loom. Use cable ties or friction tape to secure the cable. Connect the free end of the cable to the starter solenoid or battery terminal. Now find the tiny wire that was connected to the dynamo F terminal Connect it to the terminal on the rear of the alternator marked IND. Next move to the voltage regulator unit, and find the terminal marked F or DF and achieve the wire from it.

Do the same with the wire on the WL terminal. Join the two wires together, and insulate them. you’ll leave all the opposite wires attached to the voltage regulator – it acts as a useful junction box.


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