Noticed another of my heatshields (2010 XKR) was loose at the weekend, this time the one below the fuel tank. This has happened a few times on the different shields, usually they dissolve around the holes where they're fixed to the car. I'd obviously "fixed" that one before as when I took the nuts off the studs on underside of the tank straps there were fairly large nylon washers there, I remember putting these onto a number of the fixing points for heat shields a year or so back when changing the exhaust mid section.

I've changed those washers for larger ones for the time being but clearly it'll just happen again so I got to thinking about maybe ditching the OEM heat shield and replacing it with some sort of self-adhesive heat-resistant tape or mat. Has anyone done this already and if so, how did that work out? I live in Scotland where it is known to rain from time to time so that may be a show-stopper...

 

Check out DEI Floor and Tunnel Shield. I use it on my MGB to keep heat out of the cabin and it does an excellent job.

Another idea is to switch to aluminum washers to stop the galvanic corrosion that eats away at the heat shield.

 

It did occur to me when replacing the tunnel heatshield for the second time on my 2007 XK that temperatures in the UK hardly make them neccessary.

Graham

 

Thanks, I'll check that out. Regards alu washers, not a bad shout and will work on some heatshields but probably not the one for the fuel tank; that shield is screwed to the fuel tank straps (there are threaded studs on the straps) and those straps appear to be made of steel. I had nylon washers on them and they still got eaten through.

When I got my old 4.2 XKR it didn't have the rearmost heat shield at all, the one above the rear silencer. I didn't replace it for a couple of years, until I was swapping to an aftermarket silencer and I had no issues with that shield being missing. That's right at the back of the exhaust system though, I would imagine the further forward you move up the pipes the hotter they'll be. Given that this shield is right under the fuel tank I guess it's probably desirable to have one in place there?

 

I replaced the rear one but it isn't shielding the "saddle" fuel tank.









Looking at the photo again now, I wonder if part of the shield is missing. The damaged tunnel section is visible which I did replace but there was no protection around the fuel tank.

Graham

 

Pretty sure there’s no shielding on mine either near the fuel tank, probably figure hot gas will burn better.

 

According to SNG Barratt's online parts catalogue, looks like the 4.2s never had a heatshield under the fuel tank...

 

OK I'm interested to try this. How well does the stuff stick on? Do you have any in areas which will be subjected to rain and muck etc. off the road and does it hold up OK there?

In anticipation of having to change these at some point too, did you have to drop your middle exhaust section to change that shield out?

 

YES - there isn't enough room to rotate the shield around it without having to bend it but it's quick and easy to remove/refit the centre section:










Graham

 

Thanks for that. I thought that section was in two parts, left and right but obviously it's there to protect the prop shaft as well.

 

Old and new:




Graham

 

Thanks again. I can see why that needed replaced That dark patch on the old one, if I'm right then that's fairly near the rear when that was on the car, maybe just above the rear resonator in the center section? Maybe heat marking or something else?

 

I didn't take a photo with the centre section refitted so can't be absolutely certain where that black patch was in relation to the resonator.

Note in the comparison photo in post #11, the shields are facing in opposite directions. There is a recess stamped into the new one corresponding to the location of the mark on the original.

Graham

 

Yeah I spotted that the old and new shields were oriented the opposite way round; looking at the second photo in post #5, the holes in the horizontal sections where the cross brace under the exhaust goes seems to line up with the dark patch. Looking at posts #5 and #9 that dark patch would seem to roughly line up above the rear resonator and below the center join in the prop shaft.

 

You may try to fabricate a large washer using similar material like here

https://www.ebay.com/itm/163918900550