Thread: Attention All Puma Owners

The exact same electrical fire engulfed the cabin of my Puma about a month ago, complete with snapped handbrake cable and reduction in number of remaining years to live.

Unfortunately mine happened after the battery broke free in the battery box during an excursion off road whilst touring one night. As a result I didn't realise it was shorting until the handbrake cable grommet was well alight.

Initially I thought the whole under-body had gone up and the flames were just lapping through the handbrake assembly rather than being the point of ignition. A lot of possessions were thrown out of the car at great pace for no reason! It was extremely relieving when I realised it was only the handbrake that was alight.

I'm confused, why does a positive short to the seatbox go through the hand brake cable to ground when the seatbox is bolted to chassis mounts?

Originally Posted by manic

I'm confused, why does a positive short to the seatbox go through the hand brake cable to ground when the seatbox is bolted to chassis mounts?

I would think that the seatbox - handbrake cable - handbrake - engine - battery would be a conductively better path than body - chassis - engine - battery?

If the negative terminal is ground to the chassis and the seatbox is bolted to the chassis I would NOT have guessed that the handbrake cable to the transfer box route is the least restrictive.

I would have guessed: Seatbox - mounting bolts - chassis.
Good job I'm not an electrician.

Anyway perhaps the best thing to do to prevent this kind of short is to line the battery box with rubber and have a rubber mat that sits on top of the batteries. That way even if something comes loose it would be hard for it to short out.

Of course you would still need to be careful removing the terminal connections with a spanner! Remember negative terminal first

Originally Posted by manic

If the negative terminal is ground to the chassis and the seatbox is bolted to the chassis I would NOT have guessed that the handbrake cable to the transfer box route is the least restrictive.

I would have guessed: Seatbox - mounting bolts - chassis.
Good job I'm not an electrician.

Anyway perhaps the best thing to do to prevent this kind of short is to line the battery box with rubber and have a rubber mat that sits on top of the batteries. That way even if something comes loose it would be hard for it to short out.

Of course you would still need to be careful removing the terminal connections with a spanner! Remember negative terminal first

Sorry yes I added the engine into the second route which it wouldnt be, but still it would take the path of least resistance and the distance between the point of the short and the handbrake cable was probably less than the distance between the short and the chassis bolt and back to the terminal?????

Im thinking out loud now so if there is someone with a qualified response

Im thinking out loud now so if there is someone with a qualified response [/QUOTE]

I too would like to hear from someone qualified about this.

Maybe as Chook73 said another lead from the body to the chassis to ensure a proper earth.

Jim.

I won't say one way or the other about my qualifications, other than there are people about without formal qualifications that do know something.

I would be looking at the all the existing earth points first, to see if any of those points need their point of contact cleaning of paint, rust and / or anything else that is resistive to current flow.
.

Originally Posted by wrinklearthur

I won't say one way or the other about my qualifications, other than there are people about without formal qualifications that do know something.

I would be looking at the all the existing earth points first, to see if any of those points need their point of contact cleaning of paint, rust and / or anything else that is resistive to current flow.
.

Yes I agree,but is there a dedicated earth between the body and the chassis or just that its all bolted together so it should earth somewhere?

Jim.