Rear silencer rattling after marshall’s fire extinguisher(s)

[legalknievel]

Hey everyone.

I had a small and fortunately not very serious off-track excursion the other day but ended up with the rear of the car slightly wedged in the plastic barrier covering. The 996 Cup rear silencer then proceeded to set fire to said barrier covering, which was a bit alarming at the time. Marshalls were over in no time and blasted it with extinguishers. They may have done powder and then foam. I’m not sure. Definitely powder featured. The engine bay is fine, just a bit dusty, but the exhaust is now blocked and when I’ve taken it off it rattles as if there are very small stones in it.

I’m trying to decide if I should get a pro to look inside to clean it and get rid of what’s in there and sew it up again, but I guess there’s little point if the rattling is pieces of the metal structure. If it’s hardened foam particles it’s probably worth investigating for repair I guess. The replacement part is several thousand new and even used ones are crazy money.

Does anyone know enough about fire extinguisher after effects and the internals of a cup exhaust or any motorsport exhaust to have an idea about the nature of the new arrivals in the muffler?

As usual, thanks for anyone who has any idea about these things. I am out of my depth and in the usual cold sweats that come before a financial lesson on keeping within track limits.

Joseph AKA Legal Knievel

[mmm-five]

We are trained to use powder first and then foam second - but I doubt the marshal's use of the fire extinguisher would have caused any damage to the exhaust...unless they used it as a mallet a few times.

Without knowing the construction of the exhaust it'd be difficult to guess what damage the impact caused - maybe there is gravel in there, it gets everywhere.

[legalknievel]

Thanks mmm-five. Yeah, I was very grateful that the marshalls were there and knew what to do fast. I think I'm going to ask my engineer friend to open it up and investigate. If it's just gravel I'll be very happy indeed! I think the runoff was mostly grass, but it does sound like small stones when I shake it.

mmm-five said:

We are trained to use powder first and then foam second - but I doubt the marshal's use of the fire extinguisher would have caused any damage to the exhaust...unless they used it as a mallet a few times.

Without knowing the construction of the exhaust it'd be difficult to guess what damage the impact caused - maybe there is gravel in there, it gets everywhere.

[QBee]

If you went via a gravel trap, then that is what is in there. I visited a gravel trap once on a track day and we were digging loads of the stuff out of all sorts of places for weeks afterwards.