Battery mount failure

I had a problem on the last track day I did (Abingdon April 2014). I learned to brake harder and later. Mid afternoon, and with a passenger for maximum effect, the car cut out after a corner. After coasting to a stop in a safe place, it restarted, so I nursed it back to the pits. The rear mount for the battery had ripped itself out of the panel it was riveted to, and part of the mount itself touched the positive terminal and caused a short. Luckily it was only temporary and dislodged itself.

After identifying the problem, I refitted the rear mount but poking it through the panel and using a nut and washer. This meant it was now too short, and so the gap was tied together with trusty cable ties.

This worked well, until 8 minutes or so into the next session, when the problem re-occurred. This time though, it is the front mount that has ripped out and sent the mounting hardware diagonally across the battery, again greeting the positive terminal like an old friend. And so begins some impromptu arc welding under the FW bonnet, with associated sparks.

I’m pretty sure I’ve never unlocked and opened the FW bonnet so quick! I use a set of keys to remove the shorting mounting because they’re insulated. However, once that is done, I decide it’s safe to use my hand to make sure it doesn’t reattach itself. Naturally, it’s still bloody hot! The marshals arrive at this point and disconnect the battery for me, and even push me back to the pits!

Near doom

You can just about see in the photo where the front mounts have ripped out (of the chassis tube, not the aluminium panel in this instance) and where it’s nearly burned a hole in the side of the battery. This could have been a lot worse!

In hindsight, I should have seen it coming. That’s quite a tall heavy battery, so the moment created at the top under heavy braking must be pretty large. Certainly large enough to rip rivets out. I’ve since replaced the battery with a smaller, lighter Varley Red Top 25, kindly donated by Stuart (another Swindon Westfield owner). This has been mounted horizontally using a powervamp bracket.

Certainly got lucky there, being a track day if the car had caught fire I’m not sure if it would have been covered on insurance or not.

This entry was posted in Problems, Track days. Bookmark the permalink.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s