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Discussion Starter · #1 ·
So, I think I know my next steps, but figured I'd posted. Last year I replaced a failing alternator, and also did the voltage regulator and the alternator harness. The regulator I bought was a generic unit.

No idea if the battery was boiling over prior, but was definitely doing it after these improvements. So, this year I replaced the voltage regulator with a Ford unit and even replaced the entire headlight harness. All wiring in the engine bay is now new. Not to mention, cleaned up the fender apron and installed a brand new battery tray.

So, drove the car for the first few times this past week. The battery is still leaking out of the caps! I assume my next step is to pull the alternator and have it checked. Maybe it's a bad unit I received last year. Anything else I should check?! Thanks!
 

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Maybe it's just too full and it certainly has been hot... you only need enough electrolyte (sulphuric acid solution, not just water) to cover all the plates even when the car corners, it doesn't hafta be slam full. You can have the charging system tested all together on a running engine and help diagnose it.
 

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If the battery is weak or dieing the alternator will be continuously trying to charge it by sending 14.5V to it which may cause it to boil over. You'd be surprised how hot a weak battery can get when the alternator is trying to charge it.
 

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AGM is the way to go.
 

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I would definitely check to see what it is being charged at. I'm thinking the alternator is overcharging. Rufus68 has a good idea.
 

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Discussion Starter · #7 ·
Thanks guys. The battery itself is only a few years old, and I’ve never serviced it (good or bad). It has no lack of power for starting.

If anything, I assume the fluid is low now. Could low fluid cause it to boil? I can check the level.

I like the idea of grabbing one of the those digital gauges and potential bringing to car to parts store for a check.

Thanks, I’ll report back!
 

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Use a multimeter to see what the resting and charging voltages are. The shop manual has the voltage specs for the proper voltage which IIRC is @ 2000rpm. If you're over the spec, that's your problem. At that point, I'd start by cleaning and securing all battery cables, ground cables and alternator connections. Be sure your voltage regulator is securely fastened with good ground continuity.
 

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Every battery I have seen boil over was due to overcharging- In my personal experience it was the regulator- Unfortunately theres a lot of crappy "new" parts out there- usually electrical- that are bad or fail quickly- so new parts doesn't mean much. Wal mart and advance auto/autozone electrics especially

Also be aware some of the concours parts sold by various companys sometimes are for show- not really for running around.

example: New pretty yellow top coil- lasted around 8k miles- I shoulda read up more prior to purchase but after it failed I realized it was for the show circuit- not really for daily operation. Correct plug wires have the same disclaimer (but I am still running them- and so far so good)
 

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From the time I first serviced my 2008 Ram 1500 the battery top was always damp and I'd get significant corrosion buildup on the terminals. I'd clean it regularly, use anti-corrosion felt washers, protectant spray, etc., to no avail. Finally, last winter, my 10-year old OEM battery finally died. I replaced it with a new Interstate. Guess what? No more problems.
 

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Discussion Starter · #11 ·
Thanks for the added tips guys, especially on checking grounds. I have a multimeter, so can hopefully do some troubleshooting shortly. True, the battery could be suspect too.
 

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You might try just having the battery checked at any of the parts stores. Maybe it is on it is in the process of going bad.
 

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Discussion Starter · #13 ·
Hey guys, finally got around to messing with the system. Cuz still getting some spilling. I’m realizing now I probably needed to be a bit more precise on where I took the readings, but here’s what I got:

Using a multimeter, got 14.25 at idle, and when turned off, the voltage declined as expected (snapshot at 13.1). I think when revving the engine it went up to high 14s.

So, then I used this Sears machine, which a coworker gave to me. (Looks like the machine they hooked up to Eleven’s mom’s brain! - name that series).

Voltage was around 15.5 - 15.8 and didn’t really budge when revved, and never pegged out 16+. I did a few checks on the alternator and seems to be charging properly. I didn’t completely isolate the alternator and check the field, but seems to be operating normal based on the basic tests.

So, still may bring it to Advance to see what they find. I never refilled the battery, so not sure if low fluid can lead to boiling too? Maybe it initially boiled over due to a cheap regulator, and now cause the fluid is low? It’s a Bosch battery, so I would think it’s a good one.

BTW, pretty cool device. I think it’s the first time I’ve actually seen the rpms for this car!





 

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When my cars voltage regulator was failing the lights would light up brightly and the sequential flasher was faster than normal- at times. It seemed to test out OK but a few light bulbs burned out. Then the caps blew off the battery sending battery acid all over and onto the exhaust manifold while I was driving...
 

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Max voltage you should expect to see is 14.1 to 14.4V (MAYBE even 14.7V briefly?)... def not high 15's!

Sent from my SM-G950F using Tapatalk
 

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Discussion Starter · #18 ·
So what’s the punch line? Get a 3rd regulator, 2nd alternator, or battery? For grounds, all wiring going to and coming from the starter solenoid and alternator are new. I think the only one I haven’t replaced is the ground for the block.
 

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So what’s the punch line? Get a 3rd regulator, 2nd alternator, or battery? For grounds, all wiring going to and coming from the starter solenoid and alternator are new. I think the only one I haven’t replaced is the ground for the block.
Verify, clean and check rounds first, before replacing parts. Poor continuity or lack thereof will cause all sorts of odd problems. Verify the VR has a good solid ground connection as well. IIRC, 68s will have the factory chassis ground from the upper starter bolt to a stud on the firewall.
 
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