kishy's 1984 Town Car

[kishy]

Both interesting points that I'll look at. 130A 3G is in place, I'll have to check out the alternator grounding. I confess that I painted (well, primed and sealed) the upper mounting bracket for it, so 100% of the grounding needs to be happening through the bottom mount.

Also the ground from the engine to the body is original. It's been on the to-do list for a while now. Main battery positive and negative are new, and it got the charging cable out of the alternator donor Taurus, so everything is decent except for that (rather important) ground which is iffy.

[gadget73]

i painted my bracket so well once that the alternator did not charge at all. That was when I did the cam swap and the first startup with low voltage was a real WTF moment. Found it with the voltmeter, and a hit with the gasket grinder to remove some of my fresh paint sorted it out nicely.

[Tanner02480]

Do you have an aftermarket radio or the oem one ?

[kishy]

Do you have an aftermarket radio or the oem one ?

It's original:



(old photo now)

The sound system is unmodified, with the exception of using newer year stock (premium) speakers made of a more durable cone material.

[TecNickal]

I have an amp from an84 Cartier. Do you want it? Also have all four lense housings...any interest?

[kishy]

I have an amp from an84 Cartier. Do you want it? Also have all four lense housings...any interest?

Since I presume you can bring that to the Detroit meet...yes on the amp, and depending on what lenses are in question, very probably yes. Will message you.

[Tanner02480]

It's original:



(old photo now)

The sound system is unmodified, with the exception of using newer year stock (premium) speakers made of a more durable cone material.

Ok, so you should be right, the missing noise supressor may be the origin of your problem

[kishy]

At the Detroit meet, Nick hooked me up with the amp mentioned above. It is E4VF-18B849-AA. My car had E4VF-18B849-AB (the same part, but the next revision).

(everything broken about my original was done before I owned the car)




Connectors are the same. Plugged it in and it works. Same alternator-ish noise as before though. AA has metal mounting legs that ground it to the body. AB has plastic ones to isolate it. They must have discovered a ground loop-type issue when the amp is grounded and isolated it so it only grounds through the wiring. Anyway...

The electrical noise was getting quite extreme by the end of yesterday and a new symptom appeared where, if I turned off the radio to shut the noise up, a few minutes later the front right speakers would start clicking at a pace coinciding with engine RPM. Cool!

Had enough of that crap. This morning, found the noise cap, re-introduced it to the car it came out of many months ago, and got that taken care of. At the same time (in retrospect I should have done these separately) I added a nice thick ground from the alternator casing directly to the fender, using ex-1G charge wire for this. One or both of those changes seems to have shut up the noise. There is still a faint whine that follows RPM but considering component age, I'm not concerned about it. At least I can hear myself think now.

[Tanner02480]

Great job ! now you can enjoy the silence !

[DerekTheGreat]

mmm look at that coffee can. The best part of waking up, is Folger's in your cup! (No, not really. That stuff tastes like ass. Reference scene from Pulp Fiction about "that good gourmet shit."

[kishy]

Annnnnd the noise is back.
Noticed it yesterday but only while the blower motor was on.
Now it's back in force.

As I shut the door, dropped it in gear and bumped the throttle to head down my driveway this morning, the final "ding" of the chime became choppy/broken up as engine RPM increased.

I believe, though I am not certain, that this means I have yet another failing junkyard 3G on my hands. Thoughts, folks?

Note there is no 'mechanical' whine outside the car (e.g. blown diode). It only comes through the speakers and chime.

Part store lifetime warranty new alternator will be $202 Canadian after core; application is 96 Thunderbird 3.8 (130A with regulator clocked the same direction as the upper mounting ear) which is what is on the car now.

RockAuto, new without pulley is $129 Canadian shipped (to Canada) with no core. With pulley is 2 bucks more.
Trying to decide if lifetime replacement with in-store convenience is worth $70. It's not clear to me that it is. It's also not clear to me that it's the alternator at fault, but it seems plausible.

[DerekTheGreat]

That or the capacitor thingy blew??

[Tanner02480]

Let me suggest you a simple test:

plug your battery to an other car's battery with booster cables, start and let on idle the other car, then, turn the key to ACC with radio on, listen if the noise is here.
Then same thing with key to IGN ...
you car will be powered by the other car alternator and you will be sure if your trouble is this part or not.

[gadget73]

Haul the alternator to the store and have them stick it on their tester. That should tell you if you have a bad diode. Depending on your meter, you may just be able to set it to AC and see if you read anything. It should not. If its an analog meter, its probably not going to work right unless its a Simpson 260 and you're using the "output" jack to connect your test leads to. Other analog meters with a DC blocking cap will also work, I suspect the Triplett and other nicer meters from days of yore have an equivalent function.

[kishy]

I think we have the answer.

So, on his road trip, TecNickal was in town (this side of the border) and stopped by. Picked up some parts from me and we grabbed some grub with my car. If you're ever 'round these parts, you really must check out MotorBurger. Not cheap, but good. Introduced Nick to poutine and he seems to be fully on board with what us Canucks are doing with carbs (the good type) these days.

Anyway, while out, my car developed its lovely single-clunk-of-death, refusing to start. I observed with the hood up attempting to crank that there was a large blue arc somewhere in the vicinity of the battery but couldn't make sense of where it came from.

I jumped the starter relay (ugh, solenoid) bypassing the ignition switch (hooked the S terminal to battery, still operating the relay) and found it would crank with the ignition off. With the ignition on, it would not crank (single clunk). After poking around in no specifically helpful way for a while, I did get it to crank (manually under the hood) with the ignition on, and the car started. Good stuff. Got home, parked on the road for Nick to leave my driveway, and then it wouldn't start again (Nick stuck around when this happened).

Anyway, long story short, observed another big blue arc and it was coming from the battery negative terminal. I have a threaded battery shut-off, mainly so I can service high amp wires without losing my radio presets. Turns out the shut off was not firmly tightened, causing arcing between the contacts of the shut-off to the point of metal actually being pitted out of it. The car has been effectively running off its alternator due to the arcing and high resistance link at the battery negative post.

This may also explain why my headlights momentarily dimmed when I hit the brakes (the 4 brake light bulbs pulled voltage down a bit, and the momentarily headlight dim was the regulator compensating).

Eliminated the shut-off, which made the car start normally consistently, and the radio seems to have shut up again.

Check the simple things, people. I guess the new alternator in the mail won't be necessary, and I won't need to buy a new starter either. Lesson seemingly learned.

Thanks for the moral support and brainstorming with me, Nick. Not to mention if I hadn't been entertaining you, my next drive would have been tomorrow morning to work where it would not have started.