Fitting dynamator

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CyrilWhite
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Fitting dynamator

Post by CyrilWhite »

Have acquired a dynamator and rewire instructions with the kit doesn't refer to to RF59 as fitted to a Javelin.
I am not very competent with electrics and need lots of guidance to get the thing safely wired in. I intended to leave the control box in situ and use as block terminal.. Any help appreciated.
(The car is already negative earth)
PaulRM
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Re: Fitting dynamator

Post by PaulRM »

One thing I found Cyril is that you definitely have to use a smaller pulley than the one on the old dynamo, otherwise you won't get effective charging at idle. Such pulleys are available from the people who make the more expensive 'dynator' (Go the Autosparks website to see these). You will then need a slightly shorter fan belt. If you're interested I can give you the spec of mine when I next go to the garage.
PaulRM
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Re: Fitting dynamator

Post by PaulRM »

In terms of rewiring, you could run the positive feed from the dynamator to the "A" terminal on the regulator box. However the original wire going from the 'A' terminal on the regulator to the starter solenoid large positive terminal is not thick enough to cope with the higher alternator output.Therefore I ran a new thick wire (45Amp rating) directly from the Dynamator '+' to the large positive terminal on the starter solenoid (which in turn connects directly to the battery).

All that remains is to connect the ignition warning light feed on the dynamator. So, disconnect the field wire 'F' completely at its terminal at the regulator and tie it back out of the way; tie it back out of the way at the alternator end too. Use the old D wire that went from the D terminal on the regulator to the dynamo as the ignition warning light wire and connect this wire to the alternator indicator/ignition warning light terminal. I had to convert to lucar terminations (spade connectors) at the alternator end. Hope that helps.
Keith Clements
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Re: Fitting dynamator

Post by Keith Clements »

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CyrilWhite
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Re: Fitting dynamator

Post by CyrilWhite »

Regarding fitting new uprated power line to the solenoid I see there are 2 wires both brown fitted to one of the posts that are wound together with eye clip end fastening. One of these is to the horn and one to A terminal on regulator. I will have to unwind and test which brown will remain etc. What is best way of finding the correct brown to replace..
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Re: Fitting dynamator

Post by Forumadmin »

It is recommended to fit a 50 amp fuse between the dynamator and the battery. This can be done by stripping out the relays in the control box preferably using a useless one. Note how I have fitted the wiring in the SA rebuid which is a lot more complex than normally necessary as I also fit isolators on the positive feed and earth return to the battery. You can retain the control box just in case you want to swap back to a dynamo as I did for rallying as regulations changed between rallies.
Cyril,
Use an ohm meter to see which wire goes where. Disconnect the other end of the brown wires and test resistance between an end and the A terminal. Zero means a connection, infinity means no connection.
CyrilWhite
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Re: Fitting dynamator

Post by CyrilWhite »

Thank you Keith, would need auto electrician to take me through your modifications .Will definitely get some assistance.Autosparks who built the loom for me will take me through it when I go for the upgrade wire.
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Re: Fitting dynamator

Post by Forumadmin »

Please note that thicker wire needs to replace the original wire going from Dynamo to D terminal. This wire should be connected to one side of the fuse. The other side of the fuse would go to the Solenoid (or the ammeter if fitted) (what was the Control box A Terminal wire). Note that, if an ammeter is fitted, the wires to it will also need to be upgraded. The ammeter itself will go off the scale when charging but should do no damage. The other side of the ammeter goes to the solenoid.
The wire that went from the field coil on the dynamo becomes the voltage sense wire for the alternator. It is disconnected from the control box F terminal and connected to the disconnected discharge warning lamp wire that was on the D terminal.

Check that the indicator lamp is of the correct wattage of 2.2W which is the usual panel lamp filament bulb. You can check this by using a milliamp meter between earth and the disconnected D wire to the warning lamp and earth with the ignition switched on. There should be about 180 mA. Remember W= V x I so I = W / V or 2.2/12 =183mA

Alternators should not be run without a load; so check your battery and earth connections are good. The integrated control circuit might blow and can be replaced with this which I now carry as a spare. This might also happen if the wrong wattage indicator bulb is used.
https://www.ebay.co.uk/itm/282933356248 ... 2933356248

You can check operation by starting the car and seeing if the indicator lamp goes out and that you get an initial charge to the battery which subsequently drops off as the battery fills. You can also use a voltmeter to check that the alternator voltage rises when the engine is running to about 14.5v (measure voltage between body of alternator and input to 50A fuse ). If it goes much higher you may have a high resistance earth or battery feed. This can happen if you have isolators in circuit that corrode over winter.

I have not found it necessary to have a smaller pulley and use the one fitted to the dynamo. Dynamos did not charge at low revs anyway and the alternator puts out twice the current at 1000 rpm.
CyrilWhite
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Re: Fitting dynamator

Post by CyrilWhite »

Have put the job on hold, have cleaned contacts on regulator and checked dynamo and put it back. Getting charging again. Will see if it stays that way over week end. And then see if I can return Dynamator. .
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