Exhaust bolt help

votoc · 08-09-2013, 08:43 AM

Hey guys, I'm attempting to install a new exhaust and I'm currently removing the bolts that connect to the downpipes. I have sprayed PB blaster on them and the first two I tried I snapped the heads off. I'm not sure if I should continue or if I'll be able to get the broken parts out.

Has anyone encountered this?

MrPig · 08-09-2013, 08:53 AM

You'll either have to drill them out and rethread the slots or try using something like EZ Out.

That said, aren't there nuts at the other end? Have you tried rotating the nuts to see if it'll come out of the other way.

Gizm0 · 08-09-2013, 09:04 AM

Quote:

Originally Posted by MrPig

You'll either have to drill them out and rethread the slots or try using something like EZ Out.

That said, aren't there nuts at the other end? Have you tried rotating the nuts to see if it'll come out of the other way.

Check this video at 18:00 mark... These are studs welded to the cat. You'll have to drill them out, buy 4 bolts/nuts/washers to replace the ones that you broke. Remove the remaining two nuts, remove your catback exhaust so you can have access to the cats, dremel the piece of stud that's still sticking out, and then drill them out. Good luck!

MrPig · 08-09-2013, 09:05 AM

Quote:

Originally Posted by Gizm0

Check this video at 18:00 mark... These are studs welded to the cat. You'll have to drill them out, buy 4 bolts/nuts/washers to replace the ones that you broke.

Ah weak. Then yeah, drill/EZ Out and replace.

votoc · 08-09-2013, 09:15 AM

Quote:

Originally Posted by Gizm0

Check this video at 18:00 mark... These are studs welded to the cat. You'll have to drill them out, buy 4 bolts/nuts/washers to replace the ones that you broke. Remove the remaining two nuts, remove your catback exhaust so you can have access to the cats, dremel the piece of stud that's still sticking out, and then drill them out. Good luck!

Thanks, looks like he shows you at the 1:00 mark. Appreciate the link

Gizm0 · 08-09-2013, 09:18 AM

Quote:

Originally Posted by votoc

Thanks, looks like he shows you at the 1:00 mark. Appreciate the link

Yeah you're right... They're not welded but probably seized up pretty good. You can try his method, get them red hot with a torch then hammer them out.

votoc · 08-09-2013, 12:22 PM

Do you know of other ways to get them heated up without using a torch? Maybe something potentially safer. (they are soaked in PB Blaster)

kfrazie1 · 08-10-2013, 07:46 AM

Don't bother torching it, it doesn't work. This same thing happened to me. I tried torching and punching it out but it's a welded stud. Get a dremmel and cut the head off the stud flush and drill it out. Then buy 2 SS bolts and put some anti seize on them. This actually landed up taking me a full 8 hr day to cut and drill out since I was on my back under the car.

AWil335i · 08-10-2013, 08:02 AM

Mine weren't welded.... I torched them and they came out, it just took a little bit of work.

Efthreeoh · 08-10-2013, 08:37 AM

I'm going to offer some advice here, but I've not worked on the 335i exhaust (but a bunch of other BMW exhausts and many other cars too), so I'm not exactly familiar with it. I looked at realOEM and was surprised to find BMW does not offer a replacement stud (it does for many other BMW models). I doubt the studs are actually welded in because there is no reason to weld the studs in. But they probably are pressed in using what's called a "press-fit" or "interference-fit" method. This means you can press (force) them out.

If you can, the easiest way is to use an air hammer and just hammer them out. A professional mechanic would try this first. But you need compressed shop air and an air hammer (maybe a friend has such tools?). Other than that you could buy a large punch and 3 lb. sledge hammer and give that a shot. Other than that, the recommended drill out is your next alternative. If it were me, I'd get the cats out of the car and clamp them in a vice and work on them out of the car. Or just take the cats out and take them to a shop and have a mechanic with the proper tools to remove the studs for you. Most shops wouldn't charge much to do that for you.

cwarren · 08-10-2013, 08:54 AM

Quote:

Originally Posted by Efthreeoh

I'm going to offer some advice here, but I've not worked on the 335i exhaust (but a bunch of other BMW exhausts and many other cars too), so I'm not exactly familiar with it. I looked at realOEM and was surprised to find BMW does not offer a replacement stud (it does for many other BMW models). I doubt the studs are actually welded in because there is no reason to weld the studs in. But they probably are pressed in using what's called a "press-fit" or "interference-fit" method. This means you can press (force) them out.

If you can, the easiest way is to use an air hammer and just hammer them out. A professional mechanic would try this first. But you need compressed shop air and an air hammer (maybe a friend has such tools?). Other than that you could buy a large punch and 3 lb. sledge hammer and give that a shot. Other than that, the recommended drill out is your next alternative. If it were me, I'd get the cats out of the car and clamp them in a vice and work on them out of the car. Or just take the cats out and take them to a shop and have a mechanic with the proper tools to remove the studs for you. Most shops wouldn't charge much to do that for you.

+1 I would not do this while in the car then you will really be hating yourself might as well learn how to due dp replacement too

08-09-2013, 08:43 AM	#1
votoc Second Lieutenant 12 Rep 272 Posts Drives: e90 335i Join Date: Mar 2010 Location: Fredericksburg Va iTrader: (3)	Exhaust bolt help Hey guys, I'm attempting to install a new exhaust and I'm currently removing the bolts that connect to the downpipes. I have sprayed PB blaster on them and the first two I tried I snapped the heads off. I'm not sure if I should continue or if I'll be able to get the broken parts out. Has anyone encountered this? __________________
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08-09-2013, 08:53 AM	#2
MrPig Major 14 Rep 1,203 Posts Drives: '11 STI, '90 325iS Join Date: Aug 2011 Location: Toronto, Ontario, Canada iTrader: (0) Garage List 1990 BMW 325is [10.00]	You'll either have to drill them out and rethread the slots or try using something like EZ Out. That said, aren't there nuts at the other end? Have you tried rotating the nuts to see if it'll come out of the other way. __________________
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08-09-2013, 12:22 PM	#7
votoc Second Lieutenant 12 Rep 272 Posts Drives: e90 335i Join Date: Mar 2010 Location: Fredericksburg Va iTrader: (3)	Do you know of other ways to get them heated up without using a torch? Maybe something potentially safer. (they are soaked in PB Blaster) __________________
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08-10-2013, 07:46 AM	#8
kfrazie1 Lieutenant 64 Rep 553 Posts Drives: 335i Join Date: Aug 2010 Location: NY iTrader: (4)	Don't bother torching it, it doesn't work. This same thing happened to me. I tried torching and punching it out but it's a welded stud. Get a dremmel and cut the head off the stud flush and drill it out. Then buy 2 SS bolts and put some anti seize on them. This actually landed up taking me a full 8 hr day to cut and drill out since I was on my back under the car. __________________ Montego Blue E90 335i 7" VRSF IC \| OFT Tune \| DCI \| RB PCV \| Secondary CAT Delete & CYBA 3.75" Tips \| M3 Front \| Mtech Rear \| CSL Trunk \| 219M \| KW V1 \| AA CP
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08-10-2013, 08:02 AM	#9
AWil335i Second Lieutenant 12 Rep 281 Posts Drives: 2007 E92 335i Join Date: Oct 2012 Location: Indianapolis iTrader: (0) Garage List 2007 BMW E92 335i [0.00]	Mine weren't welded.... I torched them and they came out, it just took a little bit of work. __________________ 07 E92 335I \| JB4 G5 ISO \| BMS E85 Flash \| DCI \| BMS DPs \| Helix FMIC \| Alpina TCU Flash \| Walbro GLS392 \| E70 \| 429rwhp/474rwtq \|
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08-10-2013, 08:37 AM	#10
Efthreeoh General 17306 Rep 18,733 Posts Drives: The E90 + Z4 Coupe & Z3 R'ster Join Date: May 2012 Location: Virginia iTrader: (0)	I'm going to offer some advice here, but I've not worked on the 335i exhaust (but a bunch of other BMW exhausts and many other cars too), so I'm not exactly familiar with it. I looked at realOEM and was surprised to find BMW does not offer a replacement stud (it does for many other BMW models). I doubt the studs are actually welded in because there is no reason to weld the studs in. But they probably are pressed in using what's called a "press-fit" or "interference-fit" method. This means you can press (force) them out. If you can, the easiest way is to use an air hammer and just hammer them out. A professional mechanic would try this first. But you need compressed shop air and an air hammer (maybe a friend has such tools?). Other than that you could buy a large punch and 3 lb. sledge hammer and give that a shot. Other than that, the recommended drill out is your next alternative. If it were me, I'd get the cats out of the car and clamp them in a vice and work on them out of the car. Or just take the cats out and take them to a shop and have a mechanic with the proper tools to remove the studs for you. Most shops wouldn't charge much to do that for you.
	Appreciate 0 Quote