Heat shield: Important, or just for giggles?

[PHO2GR4]

So my VX has been rattling something awful ever since I had the new muffler installed. (Yes, the muffler resonates that much!) After much exploration by the friendly folks at my neighborhood Firestone shoppe, it was determined that the rattling was coming from the heat shield.

Furthermore, I apparently didn't even HAVE a heat shield...but rather, a heat-shield-shaped rust shell. It was in awful condition. The upper and lower sections were basically a crumbling mass of iron oxide chunks. They removed it, and it was just flaking off into pieces. Thanks, Florida!

Anyway. Long story longer. What's the dealio with these heat shields? Should I try to replace it with either a new one or a salvage one? One with less rust, this time? Or is it no big deal? I mean, mine was in such bad shape by the time it was removed that I might as well have had nothing there anyway.

Is it okay to drive without this heat shield, or will my VX explode? (And why do all of my problems end up with the VX exploding, in my imagination?) At least, without the rattling heat shield, my ride is much quieter now! Right up to the loud explosion, at least...

[mdwyer]

If I understand correctly, (which would be a stretch) the heat shield may be important for keeping heat IN. That is, it keeps the exhaust system hot enough so that the catalytic converter functions well.

Get a second opinion before you peel it off, but if that's really all it is, I would have no problems losing it. Besides, in Denver, the VX doesn't fit on the emissions test equipment, anyway.

[rowhard]

Eric, if it was me, I'd stop by a couple of muffler shops and get their opinion. I'm thinking the heatshield might be a needed item, if not for what mdymer said, then for keeping the heat from the muffler out of the cab, espically since your 4 legged loved ones will be residing on top of them for hours on end while you travel to MOAB.

[PHO2GR4]

Hmmm...good points.

Will I have to call St. Charles Isuzu to see if a replacement heat shield can even be purchased? This doesn't seem like an easy part to find.

Mine's gone. Powdered. Flaked off into the rusty graveyard in the sky. As I said, I doubt if it has even been effective in ages, given its powdery thinness when it was removed.

If I can find a decent replacement, I'll probably install it, just to be safe.

I'm not too worried. How hot can an Ebony VX get in the Utah desert sun, after all?

[Ldub]

With a little time, imagination, sheet metal, tin snips, a drill & bits, some hose clamps, & a pop rivet tool, you could fab up a new one in less than an hour. ;)

[nfpgasmask]

I have heard of some folks replacing heat sheilds with that silver foam tape stuff too. Probably not a long term fix...but. Anyone else know about the heat sheilding tape? I know I have at least one or two of my heat sheilds making the "jar of change" sounds under my VX.

Bart

[WyrreJ]

When the heat shield on my previous car rusted off, I asked around and was told that it's primary purpose in life was to keep heat in, in order to protect anything I parked over - like grass in a field - from catching on fire. The car ran just fine without it.

[Triathlete]

The tape will work just fine if you have enough room to get in there. Most of the comp buggies use it and have exhaust sytems that at times run very near their body (the human type) parts and often have open floors.

[etlsport]

so where is this heat shield? i was under my vx looking for it because ive got some crazy rattling going on under my vx.. didnt really see what i was looking for.. i did see a plate that looked kind of loose.. had TOD stamped on it, one of the clamps holding that down was loose so i pulled it off and put a new one on... anyone have photos of the heat sheild in question?

[PHO2GR4]

It's a two-piece, rusty, rattling wrap-around cover for part of the exhaust pipe. Passenger side of the engine compartment.

[nfpgasmask]

OK, this morning I ripped off what was left of my big long passenger side sheild. It drove me nuts all the way to and from Moab.

http://www.vehicross.info/gallery/data/2/medium/heatsh.jpg

PHO2GR4, did you call St. Charles yet? I am going to call them Monday and see if I can get a replacement.

I have been thumbing through my parts catalog to try to get a part number but I am having no luck. Does anyone know the proper Isuzu term for this part? Nothing is coming up in the index under "heat", "heat sheild" or "insulator". Any other key words I should look for? Or better yet, what "section" of the vehicle would this most likely be under? Chassis? Frame? Emission system?

Thanks - Bart

[CrnCnn]

So is this the piece that makes me feel "not so cool" when someone is checkin out the VX, then all of the sudden rattle rattle

[PHO2GR4]

Bart, if you can believe it, the remains of MY heat shield looked much worse than yours!

I've driven close to 3000 miles across searing desert heat for 10 hours at a stretch with no obvious problems, though. I wonder what this part actually does? Is it like a spleen, which can be removed without causing any bad issues?

[Dino]

Want a mechanics input... well here it is anyway! :p :p :rolleyes:

Heat shields are there to protect things surrounding that super-hot exhaust pipe! :flame2: It's fine moving down the road with air rushing by, but when a vehicle gets shut down with a super-heated exhaust, the heat rises and super-heats your floorboards and other bits that are nearby that don't take well to repeated, intense, heat! :flame:

It's best to try to keep them on. ;)
If they're rattling, any competent muffler shop's welder-on-duty should be able to tack weld them back in place.

...and there's me 2 cents.

[Joe Isuzu]

I'm definitely not the only one on this apparently, after I got mine I was very annoyed at the rattling that would happen when the car was idling, I traced it down to the heat shield and the u-bolt (right term?) had rusted, the shield wasn't in great shape but it was mostly there and I simply replaced the bolt so it wasn't sitting on the exhaust pipe, simple enough solution but sometimes I fear looking underneath my VX b/c I see a lot of rusty looking emissions equipment that soon looks like it will need to be replaced....
cha-ching!

[Knigh7s]

I have this habbit of driving next to brick fences, or wall of some sort that reflect sound back towards the car while driving. I just drop the passanger window just enough to where the wind noise isn't so loud.

Well to come to my point. I just had gotten off work the other night and have to drive through a tunnel to get home. I pulled to the far right and dropped the window down a bit. And to my suprise... an annoyingly LOUD rattle (sometimes I could hear the rattle with windows closed, but very faint, but disappears when I concentrate on that sound).

My heat sheilds are rusted up pretty bad.

(after removing the old rusted pieces) Couldn't I just wrap this (http://www.heatshieldproducts.com/exhaust_wrap.php) around it, then maybe this (http://www.heatshieldproducts.com/hp_shield.php) , and tie it down with these (http://www.heatshieldproducts.com/thermal-tie.php) ?

It could prevent it from any further rust/rattles.... ...

[/end novel] :D

[tom4bren]

I think Dino hit the nail on the head. The heat shield does not affect performance and is there mostly for safety. I haven't had any problem with it on my VX yet (but then I've only been a member for a short while and preferred to concentrate on the other VX SNAFUs first - windows, CVs). I've removed most of the heat shields from my TLC over the years (as each succombed to cancer - believe it or not there were six). No problems since. Now for the horror story though - I have heard of carpet melting because the exhaust system got too hot close to the underbelly.

I would not try for a factory replacement. You should be able to find a shop that could fab something up for you @ less $$$ and would actually last longer. Metal tape will work but my experience on an old Dodge P'up was that it is very temporary.

I've seen some ceramic coatings in the past but that was very long ago and probably are very $$$. I've also seen some fiber wrap for exhaust but again long ago and very $$$ - it also wasn't recommended as it would PROMOTE rust.

I'd recommend some leg work to find a small shop with a good welder that could fab something up for you (I'm lucky - I found such a place). Don't bother with the big chain shops. Find JoeBillyJimBob who operates out of uncle Mikey's garage. The big shops probably won't touch a job like that for liability reasons.

[nfpgasmask]

I just called St.Charles and these heat sheilds are not sold separately. They come with the whole exhaust system ($800) so it looks like I am either going to repair my existing sheilds (tack on a patch) or come up with something entirely different.

I would like to know some opinions/options on the heat sheilding tape because this seems like it would be the easiest/cheapest route.

Anyone?

Thanks - Bart

[Dino]

That heat shield tape is good stuff for race car headers and such. Kind of hard to get into tight places though and it will hold moisture. I'd use that second product listed above and the clamps! That stuff won't hold moisture as much and still do the heat shielding job.

Good find! ;)

[PHO2GR4]

Those aftermarket parts look like they'd rattle even worse.

I don't have a better solution, though.

$800...jeez.

[nfpgasmask]

Last night I put my heat sheilds back on. I went to Home Depot and picked up 4 pipe clamps, ended up using 3 of them, but I was able to get the sheilds back on nice & tight. I still have one rattling down there that I need to find and clamp on better.

Bart

[Kenny]

Are you sure it's a heat shield rattle - did it go away when you took off the shields?

I thought I had a heat shield rattle and hoped it would go away with the new exhaust system since the new system doesn't re-use the shields. It didn't, we found that it was an O2 sensor that rang like a bell when tapped - that was the rattle I heard. I replaced it and the rattle went away.

But now I have another one when I go over bumps.... :( another O2 sensor? dunno yet, too lazy and exhausted from Moab to look right now... :rolleyes:

[kelvin]

i have a bad rattle that i thaught might be bad wheel bearings, but it didnt go away when they were re-packed....

can you describe this heat shield "rattle"? mine kinda sounds like bb's in one of those rain stick things... does that make sence? like a clikity-clikity-clickity shaking thing over and over again....

[nfpgasmask]

Oh yes, this was definitely the culprit of my loud jingling. Once I removed it, the rattling from the right side immediately went away. I still have a quiet rattle on the left side though, which I am going to find soon. I just figured that even though the sheilds are rusted, I am better off with them on. And quite honestly, it was pretty easy to do. Took me about 40 mintes to get them back on nice & tight. I don't know the source of the quiet rattle coming from the drivers side, but maybe its an O2 sensor like you said. I have to get under there again and poke around.

Bart



Are you sure it's a heat shield rattle - did it go away when you took off the shields?

I thought I had a heat shield rattle and hoped it would go away with the new exhaust system since the new system doesn't re-use the shields. It didn't, we found that it was an O2 sensor that rang like a bell when tapped - that was the rattle I heard. I replaced it and the rattle went away.

But now I have another one when I go over bumps.... :( another O2 sensor? dunno yet, too lazy and exhausted from Moab to look right now... :rolleyes:

[nfpgasmask]

Yeah, that's probably it. Slide under your VX on the passenger side about 2/3s the way down and look for the loose heat shield (looks the one I pictured above). Usually though, the rattling is coming from the rusted apart pipe clamps, at least in my case, this was the situation. I pulled everything off and put it back on with some new pipe clamps. Easy. Now these don't rattle.

Bart


i have a bad rattle that i thaught might be bad wheel bearings, but it didnt go away when they were re-packed....

can you describe this heat shield "rattle"? mine kinda sounds like bb's in one of those rain stick things... does that make sence? like a clikity-clikity-clickity shaking thing over and over again....

[CrnCnn]

i have a bad rattle that i thaught might be bad wheel bearings, but it didnt go away when they were re-packed....

can you describe this heat shield "rattle"? mine kinda sounds like bb's in one of those rain stick things... does that make sence? like a clikity-clikity-clickity shaking thing over and over again....

I dont think that is the sound but I dont know that I've heard a rain stick in a long time, or ever. I have the same loose shields Bart is describing. Mine happens mostly while sitting at a stop light or when I first start the VX. I used to have a Chevy that made that noise but it was a catalytic converter that was falling apart.

[WyrreJ]

The chrome on my wheels is peeling and I get a "clikity-clikity-clickity" sound from it timed with the speed of the wheels, I just reach in and peel off the biggest chunk of chrome and that usually fixes it for a few months. Don't do it barehanded, that stuff is sharp.

[VehiX]

$800...jeez.

Sad thing is....that price is just for ONE SIDE of the exhaust!!!

Check your price listings :eek:

[kelvin]

The chrome on my wheels is peeling and I get a "clikity-clikity-clickity" sound from it timed with the speed of the wheels, I just reach in and peel off the biggest chunk of chrome and that usually fixes it for a few months. Don't do it barehanded, that stuff is sharp.


well i dont think its the heat guard... things seemed pretty tight... and i have a 99... so no peeling chrome for my little wheels.... I hate sounds i cant identify and this things getting alot of those...

[Knigh7s]

That heat shield tape is good stuff for race car headers and such. Kind of hard to get into tight places though and it will hold moisture. I'd use that second product listed above and the clamps! That stuff won't hold moisture as much and still do the heat shielding job.

Good find! ;)

My solution, as soon as I get all the parts.

Step 1. (http://www.designengineering.com/products.asp?m=sp&pid=9)
Step 2. (http://www.designengineering.com/products.asp?m=sp&pid=13)

It is way cheaper, but it all comes down to your personal preference.