First Drive today - speedo and electrically issues / help?

[Dangerous Doug]

Kramer: On my fia, I ran the speedo cable to the speedometer, then connected a drill to the other end and spun it up (got the speedo up to 60 with my drill). I wanted to check and make sure the needle wasn't bouncing (due to need for lube).

Smoke under the dash? Yikes! Do check for now brittle or bare wires.

Also, prior to fire up I had to trouble shoot my electrical a bit. Turns out I didn't have this one connected clipped in all the way. Worth a look.

By the way, don't you hate working under the dash on these things? I have to have the seat out, sit on the floor, push my butt all the way up against the rear bulkhead and slip my leg on top of the rear deck, one through the roll hoop. Then, I shimmy on my shoulders to cram myself into the footbox so I can see what the heck I'm doing under there.

I'm hoping I find my tach problem under the hood...

DD

[ZOERA-SC7XX]

Kramer, I had the same problem with charging. The car ran but the ammeter guage didn't move and the battery quickly went dead. The ignition switch light is a fused link. When you turn on the key, the light MUST go on. The fuse in the light on my dash was no good, thus no light, except that the car started and ran until the battery went dead. Charge the battery and turn on the key. If the light doesn't go on, that's the problem. Doug told me about the fused link. Good luck.

[patrickt]

Originally Posted by ZOERA-SC7XX

The ignition switch light is a fused link. When you turn on the key, the light MUST go on. The fuse in the light on my dash was no good, thus no light, except that the car started and ran until the battery went dead. Charge the battery and turn on the key. If the light doesn't go on, that's the problem. Doug told me about the fused link.

I don't understand. The red charging light is just a light that takes its 12v from fuse 5 and it gets its ground through the voltage regulator if there is no charging taking place. Other than that, it doesn't do anything at all. Where is this fusible link and how could it affect the charging?

[ZOERA-SC7XX]

Don't know how or why, just that if the link is not completed, the battery will not charge. Check with Doug...he told me about it, and he was correct. He knows what make these cars work.

[patrickt]

Originally Posted by ZOERA-SC7XX

Don't know how or why, just that if the link is not completed, the battery will not charge.

Huh. Bob P. could you confirm that there really is a fusible link tucked up under the dash and that ZOERA is not mistakenly referring to the feed to the voltage regulator coming off of Fuse 4? I've never seen a FL under there, and it's not mentioned in any of the literature....

[Kramer]

Zoera and Patrick -

I talked to Bob yesterday and he told me the same thing so I bet that is my problem b/c my light has never come on. After reading the wiring diagram I see what he means b/c it appears that the alternator (via the voltage reg) comes through that light...thus if the ciruit is not completed no charge gets to the battery. I am going to deal with the speedo first and then get back on the electrical (before I forget what I have torn apart already )

PS..I would like to retrace a lot of my engine wiring to make sure everything is set right...Is there easy way to take the dash off or peak in without being a contortionist???

Doug is so right with how hard it is to work under an installed dash.

Kramer

[patrickt]

Originally Posted by Kramer

I talked to Bob yesterday and he told me the same thing...

I was under the dash this weekend looking for that fusible link -- no luck. And I can't see how the charging light could possibly be the cause of a no charge condition. From the wiring diagram, you should be able to pull the charging light completely out of the circuit without it affecting the actual charging (via pulling the I lead off the voltage regulator, for instance). Kramer, when you get a clear answer on this please post it (along with photos too, if possible).

[strictlypersonl]

No light, no charge. The small current that goes through the light bulb is used to actuate the field circuit. It's much more than a warning circuit.

[patrickt]

Is that what that 15 ohm shunt is for? It says that's optional, so the small amount of current is actually running through the filament of the bulb?!? Damn, that is indeed tricky.

[Austin_Snake]

I had a similar electical issue a few months back when bringing up one of the Carbon Cars here in Austin for my friend, Rosanne. As soon as the alternator kicked in a big puff of smoke came out from under the dash.. On further study the ammeter had burned out. Fortunatly the wiring was unharmed. This car has Autometer gauges. After contacting Autometer I learned they discontinued the ammeter and suggest a volt meter replacement as according to them "ammeters are dangerous".
After bypassing the ameter and replacing it with a voltmeter the car runs and charges like a champ.

I have not started my car yet but it has a set of Smiths as well with the ammeter. Hopefully it will not let the smoke leak out and will work.
Best of luck with your new ride and keep it on the pavement!
Regards,
Richard.

[patrickt]

Originally Posted by strictlypersonl

No light, no charge. The small current that goes through the light bulb is used to actuate the field circuit. It's much more than a warning circuit.

Never in a million years would I have guessed that the field circuit was back-fed through the filament of an idiot light. No sign of that in the wiring diagram or the wiring instructions. But, buried deep in the bowels of the ERA web site is the diagram below that shows the optional 15 ohm shunt across the light. Does Doug wire in that resistor on the base of the light socket, or is it truly "optional?" And I take it the purpose of that resistor is to keep the car charging should the filament burn out, correct? Or if the filament is too fat to actuate the field circuit?

[strictlypersonl]

Yes, the shunt is a fail-safe alternative to the light filament. One thing to note is because of the lower-current draw of the bulb, sometimes it's necessary to initiate charging by revving the engine above 2000 rpm. Once initiated, it's fine.

[patrickt]

Originally Posted by strictlypersonl

Yes, the shunt is a fail-safe alternative to the light filament. One thing to note is because of the lower-current draw of the bulb, sometimes it's necessary to initiate charging by revving the engine above 2000 rpm. Once initiated, it's fine.

Dang, we should include that as a bonus question on the "So You Think You Know Your ERA" final exam....

[patrickt]

If your filament was to expire while on the road you could kludge it back to charging by cutting the stator lead to the voltage regulator and jumping it to any 12v power source, no? Kramer can check his system by cutting the wire headed to the idiot light, cutting the lead to the stator on the VR and jumping that to a 12v source like this. The ammeter gauge should then show a proper charge, right? And he would know for sure that his idiot light was the culprit without having to pull it out and test it.

[strictlypersonl]

Pat,

Yes, that would work. You can remove the female spade connectors from the plug with a jeweler's screwdriver, so less wire surgery is required.

[patrickt]

Originally Posted by strictlypersonl

Yes, that would work. You can remove the female spade connectors from the plug with a jeweler's screwdriver, so less wire surgery is required.

Cool. Kramer, remove the WHITE wire and GREEN wire from the voltage regulator plug and tape them off. Jumper the connector where the WHITE wire came out of to any 12v source (for instance, the YELLOW wire next to it or one of the hot fuses on the firewall). Then see if the system charges properly. If it does, you've found your problem.

[Kramer]

I will investigate this weekend

[patrickt]

Originally Posted by Kramer

I will investigate this weekend

No, you have to go out there and work on it tonight. Nothing else matters.

[ZOERA-SC7XX]

Kramer. For your benefit, that fuse/bulb is inside the warning light housing pressed into the dash. Press it out from behind after unplugging the two wires.

[fkemmerer]

Hi Kramer,

Had a chance to take some pictures this weekend and I took a shot of the Smith's style voltmeter along side the other gauges in the car. Its a pretty good match I think.



- Fred