hughdtx

First post here. I did a search ... found nothing of help. I will try to keep this short.

First off, I have a 1972 350 Coupe.

I replaced a front side marker bulb and a rear side marker bulb today. The old bulbs had no writing on them so I had to hold them next to the ones at the store and I found that only one set looked like em (12V 2825 W5W). (Oh, I realize now that I should have got the 142, after I pulled another marker bulb and it did have the part no. written on it.) So, in short, I put the wrong bulb in.

Before I realized they were wrong I plugged them in and turned on the lights (w/out key). Everything lit up great... front and back. So I assumed I got the right thing. Turned off lights.

Minutes later, I was gonna do something else so I got in the car to move it a couple feet, so instead of actually starting it I put key in first turn and put car in neutral pushed it and then gone back out. My garage smelled of smoke. There was a white smoke in the air coming from the engine bay. I popped the hood and followed the smell to my alternator and/or a spool next to it along wall of bay. I did not turn the lights on at all during this time.

Now my car won't start... no lights inside or out... no starter....(except after market alarm that taps into battery... been there for years). The horn works too.

Any ideas?

I looked around and couldn't find wires burned. I am thinking the alternator called it quits or there's a melted wire I can't see. From what I can see everything looks the same and looks good, so I think the inside of the alternator burned and created a white smoke.

Now, what caused it? Could the two little bulbs have done all that, even while being off!?

I have also heard something about fusible links. I am going to check those out tomorrow.

THANKS!

Steve Straus

Did you leave the igntion on for a period of time? The stock ignition has a braided resistor wire that can get VERY hot. It may have melted something.

As you mentioned, check the fusible link. It's down by the starter.

brooksman9

Welcome to the forum!

Larry B.

I just went through something that may interest you. While fixing my speedometer cable I noticed three melted wires going to the headlight switch. I also noticed that the headlight switch was loose when I removed it. It grounds via a metal strip embedded into the dash that would not make good contact if the switch was loose. The wires that were melted were side markers and front parking lights. High resistance in the circuit overloaded the wires but yet did not blow a fuse. You may have encountered the same witht the wrong bulbs. Logically, the fuse is supposed to protect the circuit but in my case it did not.

mrvette

LarryB, you have discovered what any decent ET knows, that with age and corrosion, connectors /crimped leads over connectors, rivits making connections on relays-the like, when these things get eroded or loose, the resistance goes up, and like any overloaded resistor, the power is lost in the failed connection, and so it smokes up, I think that's what happened to the fellow up top....just happenstance.....

BTW, this is one large reason I rewired the entire engine and pass compartment myself, done MY way....checking everything twice over, and reworking every connection, cleaned all contacts, leave NO stone unturned....

GENE

hughdtx

Ok... I found a wire that was groudn near the alternator. It was melted so I fixed that. Now car starts up great.

BUT

Headlight motors don't work now (although headlights do work)... and passenger front turn signal and side marker are out (I think bulbs are burned though)..... anyone know what could cause motors to not work? All the wiring I could see looked fine.

Thanks!

Larry B.

Go to http://www.corvettefaq.com look for headlight vacuum schematic. plent of info there.

ACECO

Headlight motors? Assuming that your vehicle is stock, then the headlight "motors" are operated by vacuum. Based upon this I would look closer at the headlight switch for a loose/damaged vacuum line, or perhaps the headlight switch itself that may have been damaged by overheating due to the incorrect bulbs.

Beyond this, see the faq as indicated above for vacuum line routing and misc other vacuum components that will need to be checked.

Good Luck!

Oh, and welcome to the insanity!




[Modified by ACECO, 1:42 AM 7/4/2004]