Removing the MSP heat shield?

[Rush]

Mm-kay.

So I picked up a semi-polished heat shield, because I'm simply too lazy to fully polish my own! I got an unexpected day off work today, so I decided to take the few minutes to pull out my heat shield and slap on the semi-polished one.

Undid the four bolts. Unclipped the plug leading to the O2 sensor. And then couldn't figure out HOW in the hell to get the damn heat shield out!

Either the O2 sensor was in the way, or more shit was in the way, or some other crap was in the way, or yadda yadda.

For those of you that have removed your heat shield, did you wind up removing the O2 sensor from the exhaust manifold for the switch? Or is there some trick to getting the shield off without removing the O2 sensor?

Oh, and yeah. When I pulled off the heat shield as far as I could, and got a look at the actual exhaust manifold for the first time EVER -- it looks like the fucking thing is cracked. I'm no manifold expert, and I know little about our stock exhaust manifolds -- but if there's a crack, is it possible that just the 'paint' or 'finish' has cracked from the heat over time? Or is my manifold itself actually fux0red?

[CustomMSP]

Welcome to the "Cracked Exhaust Manifold" Club (first)

As far getting the heatshield off, you have to have it at a certain angle and it should slip out from between the O2 sensor and the Coolant line.

[BOOSTR]

Yep, comes right off with a little finessing. No need to remove the O2 sensor. allthough doing so would make it easier for sure. It doesn't take long at all with a buffer and compound to polish the shield. Thats a good thing as over time, you'll need to do it again if you want it to look shiney like the first time.

[Rush]

Son of a bitch! I don't wanna be a member of that club! Can't I revoke my membership?! LOL.

Any tips on just what that 'angle' is? Or if it's too much of a pain in the ass to write down, I can just pester you about it when I'm there on Thursday I guess, hahaha.

P.S. -- So how much is stuff getting screwed up by the cracked exhaust manifold? I wouldn't think it's anything too dramatic. PleaseGod.

[CustomMSP]

Depending on the size of it, just a little slower spool up and a little richer over all a/f ratio.

[low_psi]

I always have removed the o2 sensor to give me more room.

[msp35]

Cut the opening on the heatshield so you can just pull up. :)

[SergMSP]

oh shit..i should do this just to see if mine is cracked...

[levison]

same thing happened to me. i took the sheild off n the manifold was cracked down the middle. i took it to the dealership and it was under warrenty.

[Jaysanooch]

So what...a cracked exhaust manifold is not obvious to the ears? I'm scared to look now.

[ChopstickHero]

found it easier to take O2 sensor out first. then wiggle the heatshield out.

[MSP#735]

^^ exactly. you also have to hold your tongue JUST right....i have never once had to remove my hot pipe, simply romove the 02 sensor and just the right angles and there ya go!

[silvermsp]

What kinda noise does the manifold make ?? when Cracked???

[silvermsp]

What kinda noise does the manifold make ?? when Cracked???

[smo0f]

kind of like a poooooosh sound, as opposed to pooosh.

[MrDiggler]

I pulled my shield loose a couple of weeks ago just to check the manifold. Thankfully I'm not a member of the club (yet). I was also wondering what you had to go through to get it out. I'll try it without removing the O2 just to see if I can do it too.

[Brian MP5T]

You would be able to feel the leak with the car running..

Use your hand..

[Rush]

same thing happened to me. i took the sheild off n the manifold was cracked down the middle. i took it to the dealership and it was under warrenty.
Yep, exactly how mine is. A nice five-inch long crack right up the middle between the two runners. And there's another crack starting between the right-hand runners, though it's only about an inch now. I have no doubt it'll get bigger, though.

Too bad my warranty has been gone for about 5K miles. I bet it was cracked before that, and I just never even thought to look.

Anyway! As far as removing the O2 sensor -- correct me if I'm wrong, but. You need to remove the four bolts, and then wiggle the shield forward a little to get clear access to the O2 sensor bolt, correct? Cause unless my heat shield is weird, the shield covers up the sensor-bolt-part.

I'll definitely check to see how badly my manifold is leaking, though, as soon as I get my car back from alignment. And if I have time, I'll snap a pic of the manifold cracks today. Not sure if my schedule will permit it, tho'.

[Alejo_NIN]

Oh, and yeah. When I pulled off the heat shield as far as I could, and got a look at the actual exhaust manifold for the first time EVER -- it looks like the fucking thing is cracked. I'm no manifold expert, and I know little about our stock exhaust manifolds -- but if there's a crack, is it possible that just the 'paint' or 'finish' has cracked from the heat over time? Or is my manifold itself actually fux0red?
is the manifold cracked..if you see a black line and the heatshield shows black smoke behind..
i guess the heatshield is mazda's excuse for that piece of shit manifold...

is the reason why i refuse to put a heatshield back into my car ...last time i decided to take the heatshield off, the stupid manifold was cracked...ARRGGHH


anyways..have fun finding a mani...
maybe MAM's tubular?? $$$

[CustomMSP]

A crack can easily be repaired if you can find an exhaust shop or a regular shop with a torch. You'll need need to purchase a few brazing rods for like $10 at pep boys or anywhere else they're sold.

[msp35]

Well that's awesome info.

[Rush]

A crack can easily be repaired if you can find an exhaust shop or a regular shop with a torch. You'll need need to purchase a few brazing rods for like $10 at pep boys or anywhere else they're sold.
Sweet! .. What material type of brazing rod should be bought? I've never even paid any attention to 'em before. Then again, maybe I should start to, since shit seems to be cracking all over the place on my car. Ugh.

[tunersteve]

I helped Joker remove his heatshield when I painted mine, and I unclipped the 02 sensor, then rotated everything around and it came out with a little effort. A bit of a heads up though, its a PITA to get that wiring clip off the first time.

[Bala]

Sweet! .. What material type of brazing rod should be bought? I've never even paid any attention to 'em before. Then again, maybe I should start to, since shit seems to be cracking all over the place on my car. Ugh.
I'd like to know the best material to use as well (future reference / just in case) Here's something that should make you feel better - If you can toast a marshmallow, you can braze (I used to teach brazing to employees in a previous career :)). You'll need the brazing rod, flux and an oxy-acetylene torch (hobby shops carry small ones). It's like soldering but on a little larger scale. Clean the area, apply flux in and around the crack (it's brush on), heat up the area around the crack and touch the brazing rod to the top of the crack. The liquid brazing rod will fill in all areas of the crack like magic. I don't know the long-term durability on an exhaust mani, but in my experience brazes are actually stronger than the surrounding area. In the absolute worst case scenario, the braze can be melted out.

[CustomMSP]

I'd like to know the best material to use as well (future reference / just in case) Here's something that should make you feel better - If you can toast a marshmallow, you can braze (I used to teach brazing to employees in a previous career :)). You'll need the brazing rod, flux and an oxy-acetylene torch (hobby shops carry small ones). It's like soldering but on a little larger scale. Clean the area, apply flux in and around the crack (it's brush on), heat up the area around the crack and touch the brazing rod to the top of the crack. The liquid brazing rod will fill in all areas of the crack like magic. I don't know the long-term durability on an exhaust mani, but in my experience brazes are actually stronger than the surrounding area. In the absolute worst case scenario, the braze can be melted out.

Anything that has Nickle in it is good for Iron. There's a lot of information on brazing cast iron on the net, just need to do a quick search on google.com

[Pyr0TeK]

I take my O2 sensor out everytime I remove my heatshield. I bought the O2 sensor removal tool from Advanced Auto for like $10 instead of just renting/borrowing theirs so I would have my own. Plus the local MSP guys here always come over so we use it on their cars also. Once the O2 sensor is removed, the cover is a breeze to remove. It is impossible to get mine off with reming the O2 sensor.


Unclip and unplug the O2 sensor wire harness.
Remove O2 sensor with removal tool.
Remove 4 heat shield bolts.
Remove heat shield.Reverse order to put back on.


Sweet! .. What material type of brazing rod should be bought? I've never even paid any attention to 'em before. Then again, maybe I should start to, since shit seems to be cracking all over the place on my car. Ugh.