Technical Help! How do I test a Marelli voltage regulator?

[Steve Laidlaw]

Would anyone know how to bench test a Marelli voltage regulator? I’m on my third one and am reluctant to install it without metering all three first. (Hoping to find any variation) Is this even possible? Thanks in advance.

 

[Toshi 975]

I spent half of last weekend trying to research this after rebuilding an alternator. Found a link to a very good video somewhere on here which tells you how to test everything apart from the voltage regulator which apparently requires a very expensive piece of kit.

 

[fiat500]

Would anyone know how to bench test a Marelli voltage regulator? I’m on my third one and am reluctant to install it without metering all three first. (Hoping to find any variation) Is this even possible? Thanks in advance.

Interesting. A few years ago I rebuilt a Marelli using new parts sourced from a UK specialist supplier of vehicle electronics components. The voltage regulation went crazy after a couple of thousand miles and I replaced the alternator with a Zelmot that I had refurbished a few years previously by adapting it with a Lucas diode pack. The Zelmot is still working, and never gives me any problems.

I have two, original Marelli regulators and two, brand new eplacements; it would be good to be able to test them.

 

[Steve Laidlaw]

Thanks for all of the info! I’ll see if I can find that video as I’m not entirely convinced that my alternator is without issue.. I’m also looking into removing the alternator without pulling the engine but I’m not sure which is the lesser evil.

 

[Steve Laidlaw]

Interesting. A few years ago I rebuilt a Marelli using new parts sourced from a UK specialist supplier of vehicle electronics components. The voltage regulation went crazy after a couple of thousand miles and I replaced the alternator with a Zelmot that I had refurbished a few years previously by adapting it with a Lucas diode pack. The Zelmot is still working, and never gives me any problems.

I have two, original Marelli regulators and two, brand new eplacements; it would be good to be able to test them.

You have me wondering about the diode pack. Is this a replaceable part? Thanks!

 

[fiat500]

You have me wondering about the diode pack. Is this a replaceable part? Thanks!

I've mis-named it; the whole assembly is called "the rectifier". I was able to track one down when I bought a selection of parts for the alternator. The images of the labelled boxes are self-explanatory. I think the company I got them from was Wood Automotive. They were very helpful, but I guess not really set up for small orders like ours.

 

[Steve Laidlaw]

I've mis-named it; the whole assembly is caled "the rectifier". I was able to track one down when I bought a selection of parts for the alternator. The images of the labelled boxes are self-explanatory. I think the company I got them from was Wood Automotive. They were very helpful, but I guess not really set up for small orders like ours.

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Bless you my friend! I'll be researching these ASAP. Thank you so much for the info!!