[mexifinn]

Hi folks.

Not sure if I should post here or in the maintenance section. Hopefully this is a quick fix so I figured here would get more visibility and hopefully a quicker answer.

I'm trying to replace my motor mount (Cobb) and running into an issue with one of the which attaches the brackets to what seems to be part of the exhaust system...

From the cobb manual:

I circled the ones giving me a hard time. They were super rusted (car is 3+ years old). I was able to remove one nut, but the other one spins freely with the bolt. I can't seem to figure out how I can get the bolt to stay so I can unscrew it. Everything else is out and I'm ready to go, just stuck with this.

Alternatively, anyone successfully do a replacement without taking that part out?

Any advice would be greatly appreciated!

 

[AKaye]

Those bolts are riveted to the downpipe bracket. If you are certain that you have broken the rivet on the bolt then the bolt is toast. I would just dremmel the bolt above the nut to get it off. Then head up to the hardware store and buy a new 2inch bolt with two washers, a locking washer, and an applicable nut to replace the damaged riveted bolt.

 

[LMStone510]

The two nuts you circled in red attach to two studs on the downpipe support bracket.

If one of the nuts is truly turning with the stud (and you can see this by using a box wrench to turn the nut), then the weld attaching the stud to the downpipe bracket has broken, and you'll likely need to use a nut splitter or grinder to remove the nut.

The downpipe is pretty heavy, since it contains the catalytic converter, so that support is pretty critical for not putting stress on the turbo housing. Probably you can replace the loose stud with a bolt, but I wouldn't be keen to run the car for any longer than necessary without both studs in place.

Here's a pic; the stock downpipe is on the top and the end that bolts to the turbo is on the right side. A new race pipe is below the factory catalytic converter pipe on top:

Hope that helps,
Mark

 

[mexifinn]

Thanks guys for the advice...

I looked up a nut splitter. Will one work in this case? Those nuts aren't "square"... they are flanged a bit so that the top is wider. Also, tight area to work in so not sure if I can find a splitter small enough.

What I have done is tried to use vice grips to grab the tip while unscrewed - no dice. Also used dremel to cut a notch in the tip so I could try to use a screwdriver to hold the bolt. Also no dice.

I'm going to have to get a better dremel cutting wheel... I just have those crappy discs that came with it. Or I guess I can just try cutting the tip off then drilling into the bolt.

I did watch a video on installing the Cobb downpipe... is it that much lighter that it doesn't need any support? or think the one remaining bolt will be enough support?

Thanks guys for all of the advice!

Gonna have to pick this up tomorrow, but will let people know what the results are...

 

[LMStone510]

Thanks guys for the advice...

I looked up a nut splitter. Will one work in this case? Those nuts aren't "square"... they are flanged a bit so that the top is wider. Also, tight area to work in so not sure if I can find a splitter small enough.

What I have done is tried to use vice grips to grab the tip while unscrewed - no dice. Also used dremel to cut a notch in the tip so I could try to use a screwdriver to hold the bolt. Also no dice.

I'm going to have to get a better dremel cutting wheel... I just have those crappy discs that came with it. Or I guess I can just try cutting the tip off then drilling into the bolt.

I did watch a video on installing the Cobb downpipe... is it that much lighter that it doesn't need any support? or think the one remaining bolt will be enough support?

Thanks guys for all of the advice!

Gonna have to pick this up tomorrow, but will let people know what the results are...

You can also use a grinder to remove the frozen stud/nut.

Catless downpipes have no bracket because they are so light, but even the "sport cat" downpipes are still pretty heavy and have support brackets, so I'd be inclined to fix this rather than run it with just one stud.

One way or the other, you've got to get the nut off!

All the best,
Mark

 

[sullyman86]

A dremel will work very well. I would recommend one of those heavy duty dremel cut off wheels since the angle will be tough to cut. Should keep the wheel from shattering on you

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[Soden82]

Do you have PP blaster? I had to use that to get those nuts off in order to install my new downpipe


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[mexifinn]

A dremel will work very well. I would recommend one of those heavy duty dremel cut off wheels since the angle will be tough to cut. Should keep the wheel from shattering on you

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Yep - got the bolt off finally with a dremel. Couldn't get close enough to cut the whole thing, but was able to put a cross cutt so I could pry it out. First hurdle done, but now I can' get the ****ing downpipe bracket off...

In this video I found, the downpipe bracket is 2 pieces, but this oval piece is fuzed to it.

Just started pouring, so once it stops I'll try to pry it off...

 

[mexifinn]

**** it. That oval bracket WILL NOT come off. I tried prying it with the back of a claw hammer, wedged a chisel into it (which I almost got stuck and took me a while to remove. I hit it with some heat - nothing.

I gotta run errands in my wifes car - if I can't think of anything by the time I come back, I'm putting it back together since I need my car for work tomorrow.

 

[Unfitproduct]

Nice day to work on the car.

 

[sullyman86]

I can't remember exactly but you should be able to unbolt the entire downpipe bracket and just remove it at this point. I think that's how I did it.

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[mexifinn]

I can't remember exactly but you should be able to unbolt the entire downpipe bracket and just remove it at this point. I think that's how I did it.

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No dice. Had all of the bolts out and none of the brackets would budge. It's like both the oval and downpipe brackets are all fused to the downpipe.


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[sullyman86]

No dice. Had all of the bolts out and none of the brackets would budge. It's like both the oval and downpipe brackets are all fused to the downpipe.


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Might be rusted a bit. Take a hammer to it. Exhaust work sucks after you have put miles on the car. Get a small piece of wood and place it up near the down pipe bolts on the bracket and hammer the end of it until everything breaks loose. That bracket is a two piece design and should come off without too much effort

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[sullyman86]

I also coated everything in pb blaster. That helps a lot

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[mexifinn]

Might be rusted a bit. Take a hammer to it. Exhaust work sucks after you have put miles on the car. Get a small piece of wood and place it up near the down pipe bolts on the bracket and hammer the end of it until everything breaks loose. That bracket is a two piece design and should come off without too much effort

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Hmm. Interesting. I did give it all a whack with a small hammer just to see what would happen. Do you mean to hammer the bracket that should come out, or to hammer up on the downpipe? In other words are we looking to just give it some vibrations or actually push it.


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[Duece McCracken]

Hmm. Interesting. I did give it all a whack with a small hammer just to see what would happen. Do you mean to hammer the bracket that should come out, or to hammer up on the downpipe? In other words are we looking to just give it some vibrations or actually push it.


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You are looking to break the rust seal. So a block of would and a mini sledge aka lump hammer would get it done.

Soak everything in PB Blaster, rail on it with the previously mentioning "persuader" setup.

If that doesn't work, then you may need to do some precision torch work. Extreme caution obviously. Im not saying cutting torch, but a little handheld propane or Mapp gas to get some thermal expansion in there.

It is boggling me that its stuck so firmly. Good luck OP.

Rofl, just saw that you tried heat, cherry red though?

 

[mexifinn]

You are looking to break the rust seal. So a block of would and a mini sledge aka lump hammer would get it done.

Soak everything in PB Blaster, rail on it with the previously mentioning "persuader" setup.

If that doesn't work, then you may need to do some precision torch work. Extreme caution obviously. Im not saying cutting torch, but a little handheld propane or Mapp gas to get some thermal expansion in there.

It is boggling me that its stuck so firmly. Good luck OP.

Rofl, just saw that you tried heat, cherry red though?

I'm unfamiliar with pb blaster otherwise I probably would have bought some today. Figured it was just like wd40. I'm 50/50 on giving up or trying to work from home so I can give it one more go at lunch. I have a kid so I can't dedicate all of my time to this Andy my wife will be back tomorrow and she's gonna need her car...


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[Duece McCracken]

I'm unfamiliar with pb blaster otherwise I probably would have bought some today. Figured it was just like wd40. I'm 50/50 on giving up or trying to work from home so I can give it one more go at lunch. I have a kid so I can't dedicate all of my time to this Andy my wife will be back tomorrow and she's gonna need her car...


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Well WD-40 is more like a set of All season tires, it does ok in a bunch of situations, but doesnt excel at anything really (except displacing water like its original intention, lol).

You need Extreme performance summer tires, aka PB Blaster. Which is a dedicated penetrating fluid designed for rust frozen fasteners and the like. It works wonders.

Sucks man, I hope it all works out.

 

[sullyman86]

Pb blaster works better at loosening rusted stuff. With exhaust stuff you really just have to make it your *****. I wouldn't beat on the actual downpipe as it's attached to the turbo. Just break the rust seal as deuce said.

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[mexifinn]

Pb blaster works better at loosening rusted stuff. With exhaust stuff you really just have to make it your *****. I wouldn't beat on the actual downpipe as it's attached to the turbo. Just break the rust seal as deuce said.

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Man that PB **** stinks.

I got some and gave it a spray. I gave it some taps and could see rust dust flying off it. Gave it some more and more taps. No dice. So i sprayed the ****ing **** out of it and will let it sit overnight.

Also I'm working on jack stands so my swing range is limited...


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