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Exhaust manifold heat shield bolts

341 Views 9 Replies 5 Participants Last post by  rowanhealy
I have sprayed sone acetone/atf mix on these bolts a couple times over a few days and tried removing them today when the engine was warm after driving the car. I only have a 1/4" wrench for the bolt size, either 8 or 10mm. None of them felt like they would budge. I have been reading about people trying to remove them, sounds like it's common they break which would be good to avoid. Anyway this is the worst one,

Asphalt Road surface Circle Soil Sand

Looks very crusty, just wondering if there is an approach to something like this, maybe hit the rust around the bolt with something? It almost looks like it's been welded on..

Any suggestions would be great.
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Yeh RIP with that, it looks really rusty. I'd try and clean it up as best you can with a wire wheel and jsut pray tbh.
Thanks, prayer it is! Hopefully it's worse on the outside than the inside!
Ah, heatshield bolts. I used penetrating oil and was super careful to ease the first one gently, and it still just snapped right off.

Unexpectedly the rest came out okay. The biggest pain is the ones which hold the two halves of the heatshield together, as the shield just wants to bend. I ended up just cutting around that. The chunk I cut off pinged away and I couldn't find where it went.

Later, when I pulled off the M25 in a cloud of steam, I worked out it had landed in the radiator fan shroud and eventually got hit by the fan, flew up and punctured my new radiator. So that was nice.

Anyway, try not to do that, is my advice.

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Would be a new radiator!

Anyway Noted, thanks


Step 1 Pray
Step 2 Don't **** up
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I was having an under bonnet fettle after work today and noticed that the heat shield looks scruffy and thought about trying to remove it to clean it up. Then noticed that the bolts looked like yours so decided to leave alone.
Im going to put a turbo in so it will need to come off, I have a bunch of other jobs to do in preparation so no rush, it will be good practice on removing rusty bolts in case there are any that really matter.
Plenty of penetrating oil, then try and tighten the bolt before undoing, sometimes helps.
I think the atf and acetone seems to work really well. The bolt in the photo rounded off but three others broke loose quite easily when I put a spanner on the end of the little 1/4" wrench for leverage. I had sprayed the mix onto them a few times, they are not as rusty as the one in the photo though. The one at the bottom feels like it's already fairly rounded. Not sure if there is any solution to this. I was thinking with the top one of trying to file two sides to 9mm, maybe there is some easier trick to try first though? The bottom one is a bit awkward to get at.
Success! Got the five of them!

I got the two that were rounded by hammering on an e16 torx socket, worked really getting the rounded 10mm bolts where vice grips were doing off.
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