Not my bike this time!

My friends '93 FLSTF Fatboy.

We just noticed her battery was about to explode?
It is a gel battery which is only 5 months old and is stated for this bike type and year.

What can cause this.....rectifier gone?

 

I had this happen to my Anti-Gravity Micro-Start XP-1. It happen just after the warranty expired.

 

Was it left on a charger ?

 

I believe it is occasionally left on a trickle charger.

 

I have had a couple of battery's do that over the years with no apparent reason One bike one Pickup

Try to find out about the charger and see if it has maintenance ability.
Test the charging system for over charging the battery, it has and can happen.

WP

 

If you want to maintain a charge on the new battery, don't use a trickle charger. You need a battery tender. That's what it's made for.

 

Don't guess. Obviously, the battery is junk. Was it defective inside. Probably.

But once bike has a new one, rev to fast RPM or with tac, 2000. Voltage should be about 13.5 to 14 depending on battery charge.

Now put the maintenance charger on it. Should read the same.

Neither should be over 15.


One needs a volt AC/DC ohm meter, a hand vacuum pump and a two ear mechanic stethoscope for Harley maintenance. All very reasonablely priced at Harbor freight.

I added a quart Mason jar with the lid drilled for a tight fit with the two vacuum hoses to bleed or use as a syphon for the pump.

Ever maintenance time on older carburetor Harley's, check the vacuum pet *****. It's s critical safety feature and needs to be on there. But you don't want it leaking vacuum.

 

Occasionally yes, I try to plug it in most of the time. It's an Optimate 3, bought new at the same time as the new battery (Jan 2022) expressly to prevent the battery dying on me!

 

IDK... maybe/probably overcharge..
I buy the least expensive AGM battery I can find.. then replace every 3 years, sometimes 4.. Zero Maintenance.. zero charging.. I aint got the time...

 

What I do. Last two AGM came from Walmart. Half what the Harley one was that did last 5 years with a lot of nursing. Walmart ones latest 4 years each easy.

A good low amp maintenance charger like Harley or Bell doesn't hurt them. However, you don't want the last start you get out the battery to be a home.

Charge if bike is going to sit a month or more ever few weeks for a few days.

I personally pull battery if it's going to sit months You don't want to take the chance of it or the maintenance charger going bad with it in the bike.

May be over kill and not even sure a AGM would spray acid but that in the fuse box would create electrical gremlins that would be a nightmare.