Heat shield repairs

[wilsonny]

Just in the midst of winter maintenance on the 993 and ive been removing my rear Pu and bumper for access to valve covers etc. Along the way I've come across the various heat shields having corroded around their fitment points. I've looked at replacements and will most probably go down this rather expensive route, but before i do, i wondered if anyone had come across the same issue and came upwith a decent quality repair that'll withstand the heat? Its a bit of a shame to replace these large heat shields which are perfect apart from their attachment points. Any experience appreciated.

Regards

Andrew

 

[Hacki]

I had this problem years ago. IIRC a tinsmith at the shop (indep. garage) repaired the heat shields and they still work perfectly. They are not visible, so it doesn´t matter to me. It was probably some cutting and welding, but way cheaper than new ones.

 

[wilsonny]

thanks for the comments - yes seems a very common problem. It looks very clear to me that there is a galvanic reaction going on at the site of attachment of the screw and shield being of different metals. Whatever I do, there's going to be a pile of copaslip going in between attachment points when I reassemble.

I'm certainly going to replace a number of the shields, but the large rear one seems a shame. I'm considering that I may use part of the scrapped shields to create repair patches for the attachment points on the large rear shield. However they are probably a bit light to weld or even braze and I am not sure what the material is. I'm investigating high temperature glues, but if I don't find something I'm happy with I will probably just end up buying all new ones.

Regards

Andrew

 

[dommorton]

I bought new shields for my last 993, and it really is a thankless expense once the PU is back on.

At the time I used some ZircoFlex to reenforce the mount points of the new shields. If I was to do this job again I would seriously consider riveting in new sections of alloy or just wrapping with sections of this stuff with washers inserted for strength.

http://www.zircotec.com/page/--zircoflex-iii/150

 

[wilsonny]

thanks - I've ended up buying most of them new, despite there just being holes at the attachments points. As you say, probably a bit thankless when it goes back together, but I have managed to repair the large heat shield across the back using strips cut from the replaced heat shields and aluminium tape. Managed to find some large flange pop rivets to secure these strips - I thought that if pop rivets are good enough for porsche to use to attach the brackets on these shields, then there good enough for my repair !

ZircoFlex looks a good product, hadn't come across that.

 

[Dekker]

I had same problem on 964 and repaired them by cutting aluminium sheet using snips and gluing over the attachment points. I then wrapped the heat shield with shiny aluminium tape. 4 years later and still looks great.