Ferret charging problems

[Frank L.]

The RCD Ferret is still having some charging problems. It's a Mk 2 with a 6 cyl Rolls Royce.

We've been trouble shooting this on and off for the past 4 years with no luck.

What is happening is the batteries will slowly drain over time and not recharge enough to stave off the amount drained.

We have installed a modern master switch to isolate the batteries from the rest of the ignition system, but the drain still persists.

I'm thinking that it is draining from the generator.....

Is this a possibility?

Thoughts? I'm sure Dan and Darrell will be along shortly.

Regards

[Richard Farrant]

Originally posted by Frank L.

We have installed a modern master switch to isolate the batteries from the rest of the ignition system, but the drain still persists.

I'm thinking that it is draining from the generator.....

Frank,

I have been involved with Ferrets for a period of over 30 years, so might be able to help. Now, if you have located the master switch correctly, it should isolate the batteries and there is no way they can drain through the system. If the switch is located correctly, then I would look at the batteries, they may be shot and are draining internally. Often a build up in the bottom of the cells does this. Get them out and bench charged then give them the heavy discharge test.

We used to have problems with the interior lamps being left slightly on, with no more than a glimmer in the bulb and this would drain the batts. over a period.

[Dan Sicotte]

There isn't anything draining the batteries....as the master switch isolates them when not in use. The FCS went through it when they rewired it. Is the Alternator/ generator putting out 24 volts?
I'm thinking that it's a battery problem aswell. The old girl doesn't get long runs in order to charge the batteries comletely. Might have something to do with the voltage regulator?
Did Rizzer overcharge the batteries with a charger..........?

Keep me in the loop.
Dan

[Lynn Eades]

First,I dont know anything about a ferret charging system.Does it have a generator or an alternator?
If it has an alternator generally speaking an alternator produces ac current which is normally converted to dc via a "bridge rectifier".
The bridge rectifier normally has six diodes in it, and only requires one to leak, to slowly run your batteries down.
This said, your isolating switch will stop this happening if it is fitted correctly.
Here is something that might not be relevant to your ferret, but might help someone somewhere. You shouldnt "tap off' 12 volts from a 24 volt system, for instance, to run a 12v radio. In this situation, one battery ends up half flat, while the other gets the guts boiled out of it.

[fv1620]

Originally it would have been fitted with Generator No.2 which is a 25A 2-speed dynamo. But if it has been upgraded it would have a Generator No.10 which is a 90A alternator.

[rob love]

There was a Canadian modification to install the 60 amp US M-series alternator onto the ferrets. This was the same alternator as used on the M38A1Cdn2 and 3s, the M151A2, the chev 5/4 ton, and currently on the MLVW. The alternator only requires 2 wires (battery and an ignition/ field source) and is very reliable. I installed it on a ferret I used to own, and it worked well. I also installed one on my FV432 to replace the troublesome pair of generators which were origional to those vehicles. That was the best modification I ever did to it, and several other guys with them ended up doing the same. It seemed like I was chasing my tail...you would replace one generator to have the other one quit. You would replace that one and the first one would quit. It never ended.

It is a fairly simple installation on the ferret, although made a lot easier by having the engine out at the time.

But I would have to agree with the rest of the guys here. If the master switch has properly isolated the ground from the chassis, then any discharge of the batteries has to lie within the batteries themselves. I ran into the same problem myself with the batteries discharging on my ferret, and also installed the master switch on the one battery box where it would break the circuit at the negative lead.

For a 24 volt system to work properly, both batteries should be in the same relative condition. Mixing old and new batteries will usually cause problems in itself.

[Frank L.]

Originally posted by Dan Sicotte
There isn't anything draining the batteries....as the master switch isolates them when not in use. The FCS went through it when they rewired it. Is the Alternator/ generator putting out 24 volts?
I'm thinking that it's a battery problem aswell. The old girl doesn't get long runs in order to charge the batteries comletely. Might have something to do with the voltage regulator?
Did Rizzer overcharge the batteries with a charger..........?

Keep me in the loop.
Dan

Actually Dan, they aren't completely isolated. The master switch isolates them from the ignition system, not the charging system.

FCS screwed it up and a real mech got in and sorted that out and installed the master correctly.....and we started to trace the drain....but to no luck at all.

I'm thinking it's the genny because it's the only thing remaining. The drain is extremely low, but it adds up over time, reducing the cranking capacity over time, not the charge itself, possibly through sulfation of the plates.

I'll take a look at seeing if an MLVW alternator can do the job. If so and the specs add up, I'll swap them out and see what happens.

The batteries are the ones in the LSVW and are exchanged when required, like yesterday. Cheapest bidder made ya know!

They are in plastic cases resting on steel plates that have been coated in rubber. Canadian Tire specials.

Rizz hasn't touched the Ferret in years.

Regards

[Geoff Winnington-Ball (RIP)]

Frank, shouldn't the master switch TOTALLY isolate the batteries? I mean nothing should connect the batteries with anything, on either pole; if it takes two switches, one for pos and one for neg, then put in two goddam switches!

[rob love]

There was a CFTO on installing the MLVW alternator onto the ferret. I think it might be posted on the ferret heaven website.

This modification also makes more room inside the ferret as you dispose of the voltage regulator to the left of the crew commander.