BLT SLA Lightset problem....

[rjsdavis]

Hello to all

I've just got my hands on an old BLT lightset to go with my retro rides - it appeared to be NOS. When it first arrived, all seemed fine, and I popped the lights together and got a nice bright output from the light.

I understood that it was a sealed lead acid battery, and the instructions basically say that these should be topped up and can receive regular "maintenance" charges when not in use - given that this might not have been touched since it first sat on the shelf. I gave her a good old long charge to re-charge the battery.

To my considerable disappointment, I barely got a very slight glow out the light this time. It was extremely dim, barely on at all, and I left it connected until it eventually went out. It stayed super-dim for about 6-7 hours or so, but you'd have barely noticed that it was on at all.

I just gave the battery another full charge - this time - nothing. It seems to be as dead as Tutenkhamun!

Therefore, is this indicative of the battery simply being really old, and was never going to work at all? Ifso, was surprised that I got any output out of her at all when it first arrived the other day. I wish now I'd left it connected to run her down straight out of the box to see how much juice was in there... However, we are where we are. Can anything be done to bring it back to life in anyone's experience?

The water bottle unit seems pretty well sealed at the moment. Anyone got experience in pulling these apart to replace the SLA battery inside? I'm assuming that it's probably a fairly stock item that can be replaced?

Many thanks

 

[dazdc5]

Re:

Sounds like its 'gassed' itself from the charging.
I had a BLT set back in the day...great spot light, if a little narrow.

It's an old system and possibly due to its age, the rubber seals have leaked liquid as gasses as its charged.

Need to open that puppy up have a look...only problem is, the bottle will be destroyed removing the battery unfortunately. Good opportunity to upgrade to a 16850 pack that may slot into a new bottle.

All connections tight and clean ... i seem to recall they were phono jack type connectors ..prone to stretching and water/dirt ingress?

 

[rjsdavis]

Hi Daz

Thanks very much for this reply - does this sound to you like I've buggered it by overcharging it, or is it an age-related thing? I do accept this is a pretty old light system to be fair to it....

I'm really not that familiar with this SLA technology - much more familiar with NiCd/NiMh and L-ion etc - had thought that this might be recoverable like an old school NiCd is from repeated charge/discharge cycles over time?

There's a nice seem all around the bottle itself, so remain slightly optimistic that it can be opened without completely destroying it in the process - was giving some thought to using a Dremel type tool to gently work round the seam, but wasn't sure how close to the edges the internals might be? Didn't want to inadvetently cut into something because I didn't know it was there. Have you ever opened one of these up?

Excuse my ignorance, but what's the "16850" pack?

I'll take some pics in the morning - suffice to say, that this battery appears to be completely NOS and never been used!

 

[Rev Cannon Dale]

Re:

my BLT's (can't remember which model, but bought in 199 and looked similar to these:

just used a 6v lead acid battery (output forgot) , similar to a burglar alarm battery from maplins. The hard part was getting something to fit in a water bottle.
The bottle did come undone; the top section will seperate with a bit of a twisty tug.
I presume you've tested to see if theres anything in the battery after charging other than trying the light?

As mentioned before, the phono connections did corrode, but also the connections to the switches were cack, and not exactly sealed underneath.

 

[FSXStumpy]

I'd bet the battery has simply aged out. SLA (Sealed Lead Acid) batteries do degrade with age, especially if they're not maintained near full charge. Even if it had, nearly 20 years is more than enough to do them in.

I've got a Cateye Daylights system that uses a similar battery, albeit in a frame mounted bag. I was able to replace the 6V, 4.5Ah battery for well under $30 at a local battery supplier. They're generally quite inexpensive.

Once you have a new one, make a habit of charging the battery quarterly, and give all the connections a good cleaning. Often just plugging/unplugging a few times, perhaps with some isopropyl alcohol to flush debris out, will do the job.

J

 

[Baulz]

You can buy a cheap 7.2v Nicad or Nimh battery pack for RC cars as a replacement that will give you more light at the expense of bulb life. Put it in a new water bottle, and use the connector from the lid of the BLT bottle.

 

[rjsdavis]

Thanks for these replies - and apols for the delay in responding before now.

I've got two systems. I've uploaded pics of them both. The black box system at the top is the older, which I recall acquiring whilst I was working at Yellow Jersey bitd - circa 1990. Even then, it was a £120 system, which was absolutely megabucks for a bikelight set at the time! This black battery system, with the switch on the side of the bottle, I think, is probably Ni-Cd based, with a battery inside (which is secured with expanding foam), and glue-gun sealed at the base to get the battery into the bottle to begin with. I've got a feeling that I can recall that one of these bottle batteries was replaced by Evolution Imports bitd and it came back looking like new after the job was done. I'm pretty confident that this can be replaced without too much bother and some time on a Winter's evening.

The newer system (the Gamma Ray) I picked up on Fleabay the other week - the seller was a trade seller, and it appeared to be BNIB and has just sat on a shelf for all of these years. I've got a feeling it's early 2000's as a system? This is by far the more tricky to replace/service as I look at the bottle itself. There's no obvious seal to the bottle itself, so no easy way to cut through and original seal, replace and then glue-gun it - although that might be the best way to do it if I can cut a nice neat circular hole in the base to gain access to the interior. As the bottle doesn't open, I can't see the internal electrics at all - I've no idea if what's in the bottle can simply be unplugged and replaced, or if it's one of these sealed and unserviceable items? Anyone know?

Many thanks

R