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anac_67
13th June 2011, 10:12 PM
I have a series IIA 2.6L 6cylinder that has issues with charging the battery. So I was told by one that the armature burnt out on my lucas C40 dynamo so I replaced that with another second hand one. I have put it in to test it out but my battery is only getting 12volts. I think I need 14 volts coming thru the battery terminals i thought? So fiddle with regulator(last time i will ever do) to adjust it above 12 volts and no sucess..

Whats going on here ?

If my regulator stuffed wouldnt the voltage be out of control?

Ana :eek:

JDNSW
14th June 2011, 05:56 AM
First question - what rpm is the engine running at when you test the voltage? Unlike an alternator, a generator will not produce much more than 12v at idle, it will need up to 2,000rpm to get 14v.

That apart, the voltage will not get out of control until the battery is fully charged - the C40 just does not put out enough current. Is the battery charged? If the generator is charging at its maximum for the rpm, nothing the regulator will do can make the voltage higher, and it will only rise as the battery becomes charged, only reaching 14v when the battery is fairly well charged.

To check that the generator is actually working, run a lead directly from the B to the F terminal at the generator and see what this does to the voltage. Also, check the voltage at the main terminal of the generator - this should rise from zero as the engine is started and revs increase and when it gets to a bit above the battery voltage the cutout in the regulator should close, and the voltage then will be the same as the battery.

Hope this helps.

John

dandlandyman
21st June 2011, 09:27 PM
A C40 generator is probably a little underpowered for your application. A six cylinder is usually fitted with a C42, which develops (from memory) about 30amps. You usually find C40s on early four cylinders where it develops about 25 amps. They were set up like that to suit the lighting needs of the vehicles. Also, I think you have to match the voltage regulator to the generator as some combinations don't work, especially if you're using the Lucas generator with a Bosch regulator. In short, it's best to know what you're doing with these systems, or have someone available who does for advice.

Dan.
69 2A 88" pet4 (in disguise), 68 2B FC pet6 (running again), plus others.