So I'm stuck, I cannot get the two exhaust bolts to come off, They are right behind the second O2 sensor and I've tried penetrating oil being drenched onto it. They are seriously stuck on there. anyone know something that I can do to remove them and maybe replace them with fresh ones?

 

If you're able to do this safely, heat is a good thing to use when bolts are seized. If you have a heat torch, you can heat up the bolts so that they expand allowing you to break them loose. #5 is what we are looking at correct? If so, be sure to heat the nut on the bolt and not the bolt itself. The nut will expand and let go of the bolt so you can walk it out. I've had to use this method a few times on my 12 year old car.

 

+1 on heat. I've wrestled with more of these than I care to remember and the only thing that really works every time is to heat it up with a torch. You'll oxy-acetylene, a propane torch won't do it unless you're very lucky. The protocol is to heat it up until it starts to glow a dull red, then let it cool for a few seconds before you put a wrench on it. It makes sense in theory, but I don't think it's necessary to try to heat just the nut, if you even can. Good luck!

 

Also if you have room an angle grinder with cutoff wheel or Dremel with wheel should work.

 

+1 on heating the nut with a torch, it will expand the nut releasing it from the stud.

If you end up Cutting it off or using a nut splitter to split the nut... the important thing is to take care to not damage the studs, unless you are replacing the that pipe, then you can cut, hack, and grind.

Best of luck.

Motor on!

 

If you heat them and they dont come off , you can cut them which then you have to replace the nuts and studs, when you reinstall add some anti seize to the threads.

Also get a new gasket when you install a new pipe or repair so it seals.

https://www.northamericanmotoring.co...d-exhaust.html

 

I had to cut mine, then started hammering on the left over piece of stud to get it out of the flange ... The hammering killed the already rusty muffler. Not a good day...

 

Hit them with some CRC freeze-off? Use this rather then PB blaster. Hasnt failed me yet .

 

a heads up - that freeze-off can help, but is really flammable. Don't spray it on hot (or even warm) parts and don't try to use it anywhere near an open flame.

 

I have hit them PB blaster in the past and it works. Yea, don't heat the bolts up and spray fluid.

 

I am trying to change out the exhaust on a 2002 R50. It's obviously not the original muffler that on there now and it has standard bolt and nut. In fact the nut looks like it might be a nylock type. I'll be cutting them off because they're all rusted. My questions are about replacement.
1.) why were / are stud type bolts used instead of regular bolts?
2.) is it that important to use studs vs regular bolts. It looks like the studs heads are installed from the exhaust side? I picked up a second hand OEM exhaust and there where no bolts / studs in it. I was planning to use regular bolts to assemble because I doubt I can find the right size studs at an auto parts store locally.
3.) any idea what size bolt to use? Any special rating? Can I use STainless steel so it will be easier to remove should I need to again?
4.) torque to 45ft lbs?

 

Those bolts are used for the stock exhaust. Above, do you have a pick of your aftermarket ?

 

Not sure I understand your question?

 

I tried 3 different pen. oils and heat. What worked for me was a Dremel tool and a cutting disc.

 

We ended up using a air saw and cutting the bolts off. HF blades and the air saw stink but finally got it done. New exhaust installed and it sounds so much better. Thanks