Adjusting voltage regulator?

Gotta love that wiring . . .
Post Reply
18Fiatsandcounting
Posts: 3798
Joined: Fri Mar 15, 2019 11:23 pm
Your car is a: 1969 and 1971 124 spiders
Location: San Francisco Bay Area

Adjusting voltage regulator?

Post by 18Fiatsandcounting »

Anyone here have any experience with adjusting the external regulator, the old stye kind mounted on the driver's side firewall?

I noticed the charging voltage in my '71 spider was between 15 and 16 volts, and although this doesn't seem to be causing problems with blowing out lights or bulbs or such, it's hard on the battery.

I came across a description for a Fiat Dino Spider regulator, and the specs appear the same as in an old 124 shop manual that I have, in the section on voltage regulators:
http://www.fiatdinoforum.org/viewtopic.php?t=1247

I adjusted the gaps and spring tension as specified, and indeed, the charging voltage now seems to be about 13 volts at idle and around 14 to 14.5 volts at 2500 rpm, which I would call close enough. I think the spec was 14.2 volts, plus or minus 0.3.

I do realize I could just go out and buy a new regulator, but there's really nothing wrong with mine, and it's basically just a relay on steroids. Other than the points being pitted or the spring losing tension, there's not much to go wrong.

-Bryan
DieselSpider
Posts: 2130
Joined: Wed Dec 24, 2014 10:21 pm
Your car is a: 1978 124 Spider with Isuzu Turbo Diesel

Re: Adjusting voltage regulator?

Post by DieselSpider »

Haven't adjusted one in almost 40 years however it was more common on cars with generators. Part of the annual tuneup on my 62 Falcon was checking and if needed adjusting the voltage regulator.

In the disposable era its gone out of fashion.
18Fiatsandcounting
Posts: 3798
Joined: Fri Mar 15, 2019 11:23 pm
Your car is a: 1969 and 1971 124 spiders
Location: San Francisco Bay Area

Re: Adjusting voltage regulator?

Post by 18Fiatsandcounting »

DieselSpider wrote:In the disposable era its gone out of fashion.
True, although I have heard that some new regulators (cheap ones, perhaps) are incorrectly adjusted right out of the box. Now that I think about it, I don't recall ever having to buy a new regulator for my spiders. I would just measure the battery voltage when the engine was off, and if it increased by a volt or two when the engine was running, I considered that good enough. Until now when I noticed that the alternator output voltage seemed to be running high.

-Bryan
redcars
Patron 2020
Patron 2020
Posts: 487
Joined: Sat Jul 31, 2010 9:36 pm
Your car is a: 1981 Spider 2000
Location: Collinsville, IL

Re: Adjusting voltage regulator?

Post by redcars »

I too have adjusted voltage regulators, but again 50+ years ago.
1987 Lotus Super 7 clone
1981 Fiat Spider 2000 AT
1982 Fiat Spider 2000 5sd
1970 Fiat Coupe
18Fiatsandcounting
Posts: 3798
Joined: Fri Mar 15, 2019 11:23 pm
Your car is a: 1969 and 1971 124 spiders
Location: San Francisco Bay Area

Re: Adjusting voltage regulator?

Post by 18Fiatsandcounting »

OK, so what I'm hearing is that I am 50 years behind the times...! :D

No worries, as all my cars are "vintage". But, I'm slowly getting used to using this fancy word processor they refer to as a laptop comptroller or something like that, along with the thing you move around with your hand. I think it's called a rodent or something like that. :roll:

-Bryan
DieselSpider
Posts: 2130
Joined: Wed Dec 24, 2014 10:21 pm
Your car is a: 1978 124 Spider with Isuzu Turbo Diesel

Re: Adjusting voltage regulator?

Post by DieselSpider »

Once they started with the solid state potting everything in with epoxy including the adjustments it kinda of eliminated your ability to fine tune them unless perhaps you were very good with a Dremel Type tool.

I go from really vintage with a completely mechanically fuel injected diesel in the Spider to my Electric Nissan Leaf.
Post Reply