Heat Shield Rattle, and how to stop it

[skierxheli]

I have a pretty bad heat shield rattle. I want to get rid of the noise because you can really here it inside the car. Is there someway to salvage the heat shield or so something to it to stop the rattling? Also, where is it?

[ragtopcav]

Depends on the heat shield; the problem is common enough, the ones I've fixed has involved a new nut and a much larger washer [a 'penny' washer]

[skierxheli]

can you explain the new nut and penny washer replacement? and where is the heat shield on the car?

[earthworm]

I had to repair the heat shield on the VW, once or twice. Fatigue wears and cracks the metal at the mounting screws - a large washer and new hardware fixes this.

I think a penny washer has a hole drilled thru it. Cheaper and better than a store bought piece.

[Ryan33]

the heat shield is located above the exhaust piping...i have a huge heat shield rattle too, and with the 3" turbo back that doenst help much either, i have to do exctly what ragtop said also with a bigger nut and washer too, just havent had the time to get underneath the car...

[ragtopcav]

Sorry; 'penny washer' is a discription of a washer that is disproportionately large in overall diameter to the centre bore diameter. A 6mm [1/4"] washer is typically 13mm [1/2"] overall diameter yes? a penny washer will be about 25[1"]-28mm[1,1/8th"] for the same centre bore. The idea is that the heat shield has rotted away from its mounts, a large [penny] washer will suffice to clamp the shield back from whence it came; also, use some copper grease upon assembly or seal in with underseal to inhibit further corrosion.

[PMI]

I think there are four exhaust heat shields. Cat, middle muffler/silencer, fuel tank, rear muffler. Five on some models, including one at the oil sump.

The one which came loose on my car is before the muffler, at the fuel tank. It is held in place with 3 (?) threaded studs which are welded to the bottom of the car. The shield has holes which go over the studs. A barbed washer goes over the shield and bites into the heat shield material. A lock nut goes over the washer.

As the car flexes, the barbs which are supposed to keep the shield in place wear away the heat shield material which is very soft. The heat shield gets loose, and starts to rattle against the exhaust pipe.

If you replace the barbed washer with a larger flat one (or insert it between the barbed washer and the shield), it will keep the heat shield in place for a while.

Although the shield is made out of material which does not rust, the stud and the lock nut can rust in place. If you happen to break the stud while trying to remove the nut, you may have to weld a new one in place using a stud welder.

[earthworm]

I was fabricating the penny washer story, Ragtop,

but I would do this if I had no "body" washers...

It would pay, if possible, to grasp the shield stud with needle nosed Vice Grips before any removal, even with PB Blaster, etc..

[tecsbrain]

Robbing an ancient but relevant thread.

Anyone know what size bolt I need for this?

[busaboy]

An effective, and allegedly Honda-approved, procedure to rectify noisy heat shields, is to tightly wrap the offending heat shield with a large hose clamp, tightening it down firmly.

[tecsbrain]

b-

Bingo, that's what I'm fittin to do. Right now I'm using a metal cable tie but it gradually loosens and the rattle returns.

Thanks for the idea.

[earthworm]

Originally Posted by tecsbrain

b-

Bingo, that's what I'm fittin to do. Right now I'm using a metal cable tie but it gradually loosens and the rattle returns.

Thanks for the idea.

On my old VW, I removed the old rotted heat shield and replaced the uninsulated exhaust pipe with straight glass pacs.
I've see aluminum flashing used on an older Saab 9000, simply replace it on an annual basis, its still much less expensive.
HF sells these metal cable ties...
No matter what is used, either the shield or the entire car must be replaced sooner or later.

[hunt.dogshome]

Sometimes the studs shear off to add to the fun. Drill up/down to suit, but watch out for brake pipes, fuel tank, helpers fingers, inquisitive cat, carpet, toolbox in the boot, spare wheel etc

[Diglett]

Hi all, its been a while since I've posted. My 900 has been great the past few months, but I've developed the rattle described here.

I traced the issue to a break in the heat shield on the bolt just to the rear of the fuel tank. Unfortunately for me, it looks like someone previously tried to repair this same hole and there was already a large penny washer there, which has now fused itself with the frame (rust or heat, it wont budge at all). The metal shield has stressed itself once more and theres not enough metal left to allow a new washer to keep it steady..

Anyhow, there's no way I can see to completely eliminate the noise short of drilling some new holes and putting a screw through (I doubt this is a good idea) . I have wrapped a hose clamp around where the pipe bangs against the shield (the bit that sticks out of the clamp is wedged between the two parts to lessen the vibration). This helps a little but its still noticeable.

Are there any softer heat resistant materials that I could affix between the shield and pipe to eliminate the sound?

[jakejm79]

Some fiberglass mat would probably work and wont melt or burn.

[EdT]

Originally Posted by Diglett

I traced the issue to a break in the heat shield on the bolt just to the rear of the fuel tank. Unfortunately for me, it looks like someone previously tried to repair this same hole and there was already a large penny washer there, which has now fused itself with the frame (rust or heat, it wont budge at all). The metal shield has stressed itself once more and theres not enough metal left to allow a new washer to keep it steady.

I used some silicone to glue the heat shield back to the body. Epoxy might work as well.

You don't want the heat shield and the exhaust to touch.

[Payne4life]

i just use some self peircing metal screws with a washer and screw it back up to the car. just make sure your not screwing into the passanger area. dont want any screws in there. ive fix all but the one over my resonator, i may try some double sided body trim tape to see how it holds.

[rrob311]

If the heat shield attaches to the body what I always do is get a rivet kit. Drill the corresponding size hole for the rivet size you would like to use. Then rivet the heat shield up next to the worn hardware. Works perfect and will not rust or loosen up.