Alternator Diagnosis

[bunnspecial]

I THINK the alternator just died on my MKZ with no warning, but before I rush into a fairly involved job I wondered if someone would be willing to look over/confirm why I suspect it:

1. Car was driven a lot yesterday(350 miles or so), most in one continuous trip. After sitting for a few hours, I went out to drive again, and it throws a "charging system error"(battery in the message center).

2. Check the voltage on the battery. Not running, 11.8V. Start and it drops to 11.6V. Revving doesn't change voltage.

3. Just to rule out everything, I pulled both cables off the battery, cleaned thoroughly, and fitted back with dielectric grease

4. Visual inspection shows alternator pulley turning

I have an alternator and belt on order, but from what I can find this is...not a small job...so wanted to make sure there wasn't something else I could rule out or check before tearing into this.

 

[wag123]

Ford uses battery excited alternators. It could actually be a bad battery. In the hot weather we have been experiencing, batteries can fail without warning. Living in Texas, I have seen this more times than I can count, and I have experienced this myself on several occasions.

 

[bunnspecial]

Thanks, and I would like if that’s the answer! It’s flirting with 100 degrees here now.

I did charge the battery overnight but haven’t had a chance to try it today. Would having it work if I start with a hopefully full ~12.5v battery point to it being a battery issue? Or, alternatively, staring with a jump pack or even just a straight jump? Just trying to think how I could tease that out as an issue without just putting a new one on it.

The battery on it is a NAPA branded East Penn bought/installed October 2019.

 

[wag123]

Thanks, and I would like if that’s the answer! It’s flirting with 100 degrees here now.

I did charge the battery overnight but haven’t had a chance to try it today. Would having it work if I start with a hopefully full ~12.5v battery point to it being a battery issue? Or, alternatively, staring with a jump pack or even just a straight jump? Just trying to think how I could tease that out as an issue without just putting a new one on it.

The battery on it is a NAPA branded East Penn bought/installed October 2019.

In the heat, I have seen batteries fail well inside of 3 years. Heat is much harder on batteries than cold. After having charged the battery, have NAPA test it. If it can be driven to NAPA they can test both for you.

 

[WobblyElvis]

The charged battery should now start the car. You have a volt meter. After the car is started, measure the voltage at the battery, if it is up above 13 volts, it would appear your alternator is somewhat working.

Near the end of your long dirve, the battery failure or charging light did not come on. This indicates to me that the alternator had not failed, yet the battery was dead a few hours later. This indicates a bad battery.

Dielectric grease in an insulator. It can be placed on top of and around the battery post after clamp installation but it should not be between the clamp and the post.

Almost impossible to diagnose this over the web, but my money is on a failed battery.

 

[bunnspecial]

The charged battery should now start the car. You have a volt meter. After the car is started, measure the voltage at the battery, if it is up above 13 volts, it would appear your alternator is somewhat working.

Near the end of your long dirve, the battery failure or charging light did not come on. This indicates to me that the alternator had not failed, yet the battery was dead a few hours later. This indicates a bad battery.

Dielectric grease in an insulator. It can be placed on top of and around the battery post after clamp installation but it should not be between the clamp and the post.

Almost impossible to diagnose this over the web, but my money is on a failed battery.

To be clear, the battery has yet to fail to start the car. It’s just well under 12v, which is why I stuck it on the charger.

My understanding has always been that grease application to a clamp type connection such as this is proper as tightening the clamp will displace the grease for proper metal to metal contact, and the remaining grease in any pits, scratches, or other places will provide corrosion resistance.

 

[Chris142]

In the heat, I have seen batteries fail well inside of 3 years. Heat is much harder on batteries than cold. After having charged the battery, have NAPA test it. If it can be driven to NAPA they can test both for you.

I hear the heat thing a lot. I'm in the Mojave desert. I often get well over 3 + years service out of my batteries. I generally replace them early just because. Got 90 months out of one,72 another etc.

 

[bunnspecial]

Well, I feel pretty comfortable now say it's the battery.

Charged it and it came up to almost 13V. Started and it almost immediately dropped to 11.5, but goosing the throttle kicked the battery light off and shot the voltage up to a nice solid 14V.

The battery I THINK is still under warranty, so I'll be visiting NAPA in a ltitle while to get one.

 

[andyd]

Did you check the water level in the battery? Not that I ever do

PS. The battery in the Fridge failed after a yr or so. I only jumped it twice, at home. Once, in case I left something on, 2nd time was to drive to Wal-Mart for a new one. I learned my lesson after only a 1/2 century of car repair

 

[ripcord]

If the battery only came up to 13V on the charger, it's not fully recharged. It needs to spend some time in the mid 14 volts range to reach full charge. If the battery can't be charged to 14 plus volts, it's gonna be bad.

 

[bunnspecial]

Well, seems as though a new battery did me no good after all...

Dropped it on the car and the alternator came right to life when I started it up, but about halfway through the drive home it seemed to give up again and back came the battery warning light.

I'm charging the new battery now, as it was down to ~11.8V when I got home, but I'm guessing it's alternator time.

Now the real question-I can't find the exact job on an MKZ, but can find it on the Fusion. It scares me a bit, though, as Fusions of this age had electric PS and MKZs had hydraulic, so I don't know if I'll have the PS pump in the way. There's one good video on Youtube that shows extracting it through the wheel well, but it involves dropping the subframe. Some other claim you can do it up-up by removing the fan. The latter certainly LOOKS possible to me.

Either way, it seems a miserable job. Why do they have to make these so dang difficult?

 

[bunnspecial]

Well, this saga hopefully is drawing to a close.

After taking what seemed like half the front end apart, I wiggled the alternator out between trans cooler lines and AC pipes...and scraped the radiator with the power lug and poked a hole in it.

Ordered a new radiator, and while I was waiting on that I went ahead and wrapped up the new alternator install. Got it in, in place, tossed a new serpentine belt on(I ordered a P/S belt also, but it's one of those stretch-to-fit belts and since honestly the serpentine I pulled off was perfectly useable, I didn't tempt fate by changing it). I'll mention too that I normally use a breaker bar or ratchet to fit serpentines, but there wasn't enough room to fit either one. I bought a fancy ratcheting tensioner tool that covers most conceivable situations(this project was an excuse for me to buy a lot of tools) and it worked perfectly and actually really well from inside the wheel well. In any case, with it all hooked up, the car started right up, voltage shot up to 14V, and all my alternator ills seem over.

I got the new rad in yesterday, refilled and burped the coolant, and then mostly finished up the rest of the job today. I have the major parts back in and everything connected. I'm waiting on some more "push pins" to be delivered to replace ones I broke/lost/stepped on. I need to get back under the car to get pipes, hoses, wires, etc re-anchored to the bottom of the radiator, and then once I put a few more of the plastic panels I removed back on I'll be done.

I know all this plastic is for aerodynamics and also keeping things clean, but it seems like any time I do anything I spend as much time taking those stupid things off(and messing with the clips) as I do actually doing the repair.

 

[drtyler]

Hopefully it works out. Sounds like a job.

Put some ac in the B and dump the Ford!

 

[bunnspecial]

Put some ac in the B and dump the Ford!

I have to admit that even with the disgusting temps, it's been nice to daily it. I don't want to push my luck-it's still registered in Kentucky on an historic tag and I don't think Illinois would take too kindly to knowing how long I've had it here on that tag...maybe that will kick me into actually registering it here. I am going to do it on a regular tag, though-Illinois historic tags are super restrictive while Kentucky doesn't spell out what is/isn't allowed and the sentiment I read behind the law is "just don't use it as your only car."

In any case, a few years ago I bought a period dealer-installed A/C system from someone that they'd pulled out of their 72 GT they were restoring. It was a fully working system-they just wanted the "clean" engine bay. One of my biggest hindrances is that the 72-76 dash is very different(with face level vents not present on the 68-71 dash). I THINK fitting a 72-76 dash would be straight forward(aside from the general pain of installing/removing the dash, although not as bad as modern by any means) and I'd get a glove box also, but also don't know that I want to do that. Plus, that's an R-12 system. I've never been totally happy with an R-134a conversion on an R-12 system, so I'd either end up experimenting with propane/isobutane or see if I could sweet talk one of the old shops into filling it with R-12.

Also, I've had to drive the B in the rain a couple of times the past week. I'd forgotten how badly it leaks. I also need to find some wiper refills. The last time I did them was maybe 2016 and the ones on it are not working the best now.

 

[drtyler]

I have to admit that even with the disgusting temps, it's been nice to daily it. I don't want to push my luck-it's still registered in Kentucky on an historic tag and I don't think Illinois would take too kindly to knowing how long I've had it here on that tag...maybe that will kick me into actually registering it here. I am going to do it on a regular tag, though-Illinois historic tags are super restrictive while Kentucky doesn't spell out what is/isn't allowed and the sentiment I read behind the law is "just don't use it as your only car."

In any case, a few years ago I bought a period dealer-installed A/C system from someone that they'd pulled out of their 72 GT they were restoring. It was a fully working system-they just wanted the "clean" engine bay. One of my biggest hindrances is that the 72-76 dash is very different(with face level vents not present on the 68-71 dash). I THINK fitting a 72-76 dash would be straight forward(aside from the general pain of installing/removing the dash, although not as bad as modern by any means) and I'd get a glove box also, but also don't know that I want to do that. Plus, that's an R-12 system. I've never been totally happy with an R-134a conversion on an R-12 system, so I'd either end up experimenting with propane/isobutane or see if I could sweet talk one of the old shops into filling it with R-12.

Also, I've had to drive the B in the rain a couple of times the past week. I'd forgotten how badly it leaks. I also need to find some wiper refills. The last time I did them was maybe 2016 and the ones on it are not working the best now.

That could be an interesting swap (the 72-76 dash for the pillow dash). I have no idea about it either, but it's probably do-able. Might be better to start with a good used 72-76 dash as the repros are a lot of work to get right.

I have a 71 B roadster that is used very often, but I have little desire to daily it when there is rain and/or 90+ heat. Great little cars though.

 

[Nesterenko]

To be clear, the battery has yet to fail to start the car. It’s just well under 12v, which is why I stuck it on the charger.

My understanding has always been that grease application to a clamp type connection such as this is proper as tightening the clamp will displace the grease for proper metal to metal contact, and the remaining grease in any pits, scratches, or other places will provide corrosion resistance.

If tightening the bat clamps displaces the grease then why bother at all. Nice clean metal to metal not overtightened. Now do as @Wobbly Elvis says and just coat the exterior of clamps and posts lightly with dielectric grease.

 

[bunnspecial]

If tightening the bat clamps displaces the grease then why bother at all.

The only places that conduct are areas where there are direct metal-to-metal contact, regardless of whether there is grease present or not. As the surfaces are not perfectly smooth, there will always be gaps.

Applying dielectric grease to the posts(or to any electrical connector before making the connection) and then tightening the clamp gets metal-to-metal contact where it can happen and "seals" any pits or other imperfections so that they won't corrode.

If you look up studies from manufacturers of the stuff and from other sources like the DOD, you'll find almost universal support for applying grease and then making the connection. Plenty of old threads around here discussing it too...

 

[Nesterenko]

The only places that conduct are areas where there are direct metal-to-metal contact, regardless of whether there is grease present or not. As the surfaces are not perfectly smooth, there will always be gaps.

Applying dielectric grease to the posts(or to any electrical connector before making the connection) and then tightening the clamp gets metal-to-metal contact where it can happen and "seals" any pits or other imperfections so that they won't corrode.

If you look up studies from manufacturers of the stuff and from other sources like the DOD, you'll find almost universal support for applying grease and then making the connection. Plenty of old threads around here discussing it too...

Coating the top of the post and the top and sides of the clamp. It's sealed from the top so no ingress of anything unwanted but you've still kept clean metal to metal on the inside.

 

[Donald]

Would it have been cheaper to have an Indy shop do the work? Given you had to replace the radiator.

Given the work involved to replace the alternator, I hope you got the best you could find.