alternator issues

[buckspet]

my 79 runs fine, but at night my alternator warning lite comes on at low speeds. has anyone ever experienced this partial some times lite coming on? The belt is tight enough, and the engine runs fine up thru 6000 rpms. no missing or other low voltage symptoms. Has anyone rebuilt a fiat alternator with the main focus on increasing the amps? I know AR sells a higher amp alternator but it's a little pricy just to put out that little light. One thought was a usa, one wire alternator at 90 amps...much cheaper. any Ideas that I haven't mentioned?

[rjkoop]

my 79 runs fine, but at night my alternator warning lite comes on at low speeds. has anyone ever experienced this partial some times lite coming on? The belt is tight enough, and the engine runs fine up thru 6000 rpms. no missing or other low voltage symptoms. Has anyone rebuilt a fiat alternator with the main focus on increasing the amps? I know AR sells a higher amp alternator but it's a little pricy just to put out that little light. One thought was a usa, one wire alternator at 90 amps...much cheaper. any Ideas that I haven't mentioned?

I had similar issue. My belt was tight. I ended up checking the grounds. My issue was the contact from the alternator housing to the engine (because I fully painted the bracket not knowing that it was used as a ground). Once I sanded it the light doesn't go on anymore.

http://www.fiatspider.com/f08/viewtopic.php?f=6&t=31449

I may also install a new ground strap from the alternator to the car body just for good measure. Also be careful when you tighten the + wires onto the alternator that they don't come in touch with the alternator housing body and cause a short.

I think it's best to start with checking the voltage at the battery... test with car off, car on, car on with lights and accessories on...

[buckspet]

thanks Richard, never thought about the alternator ground, I did clean the battery terminals, now I'll clean as many grounds that I can find...Is there any type of check list to make the checking for grounds to be more efficient particularly as it relates to this alternator issue?

[rjkoop]

thanks Richard, never thought about the alternator ground, I did clean the battery terminals, now I'll clean as many grounds that I can find...Is there any type of check list to make the checking for grounds to be more efficient particularly as it relates to this alternator issue?

I went through all the grounds I could find (under hood near front lights, under steering wheel, in trunk) , cleaned them, light sandpaper, used electrical cleaner and reattached. Also check I wasn't missing any major grounds by checking on these forums. For alternator issues I'd ensure you have the alternator body -> engine block grounded well (that's where my issue was), engine head -> chassis, transmission ground and the ground in the trunk at the battery (mine wasn't attached when I got the car).

[buckspet]

gra\eat and quick response...thank you richard

[rjkoop]

gra\eat and quick response...thank you richard

No problem. Glad to help someone else for a change. People here are always helping me...

Richard

[v6spider]

Corroded and loose connections are a common problem. The spider has absolutely no weatherproofing on any of the connections.

Rob

[buckspet]

thanks rob, seems everyone has electrical issues...ugh. btw love the v-6 install, what year is the motor

[Nanonevol]

Yeah, Rob, and what's your 0-60 time?

[v6spider]

thanks rob, seems everyone has electrical issues...ugh. btw love the v-6 install, what year is the motor

Thanks! The engine is the Chevy 4.3L V6 the block is from an 1986 Astro van.. The heads are true Vortec heads from a 2002 engine. The block is bored. 030" over and fitted with flat top small block 350 Pistons intended for a v8. Compression ratio is about 10.5:1. Heads were fitted with screw in rocker studs, roller rockers and taller valve springs to accommodate a comp cams hydraulic roller performance cam with .525" lift and 280° duration. The intake is an Edelbrock 2114.. The carb is a 625cfm Carter AFB.. roughly 300+hp and over 300ftlbs of torque on pump gas (92 Oct..).

Yeah, Rob, and what's your 0-60 time?

Not really sure.. It's fast .. Just never clocked it.. Have to be careful as it breaks loose in every gear.

Cheers!
Rob