muffler bolts - no more surprises

[nicksr]

Later today I am planning on replacing the muffler on my 93 LC with the Bosal unit I purchased.

I'm just wondering from those that have done this already, how likely is it that I will be able to get the flange bolts off with just some penetrating oil and lots of wrenching?

Or, are they likely to be rusted solid and break and I need to have some replacements on hand?

What about the flanges. Is this going to be something where I get it apart and find out the flanges are rusted and no good, or once I get the bolts off, I should be good to pop the new unit in (maybe with some new bolts) and that will be that?

 

[96r50]

I used a torch the first time and a grinder for the second time. Wrenches/pliers/vicegrips/monkey wrenches would have done nothing. You WILL want new bolts on hand IMO. My flanges were still in decent shape after a good wire brushing. You will also want new gaskets for both ends of the piece you are replacing. Since you're replacing the muffler you will also want an O2 sensor gasket and a pair of O2 sensor nuts. HTH!

 

[nicksr]

That does help, thanks.

any idea what size bolts?

Also, I am kind of lost on why I need the O2 sensor gasket and O2 sensor nuts. I wasn't planning on doing anything with the sensor? Am I missing something?

 

[96r50]

The bolts I used were either M8 or M10 by 40 or 50mm (I know, not much help). Take a look at what's on there to give you a better idea. I used zinc-coated (the gold colour) flange head bolts and nuts, since that was what the dealer had in their drawer.

Disregard the O2 sensor stuff, as I just realized that you have a 93 with the pre-cat O2s. My 96 has the second O2 sensor mounted in the pipe leading into the muffler, hence the need for O2 sensor stuff. Sorry for the confusion!

 

[nicksr]

I was able to get one bolt out intact. Took that and bought 4 sets.

Was able to get one more out intact. Ground off the head of one in the rear then cut the pipe to drop the muffler to grind off the head of one in the front.

Just need to bolt up the new muffler now.

Any idea on torque for the muffler bolts?

 

[96r50]

My 96 FSM says 29 ftlbs for both connections. I just used German torque (Guden-tite!)

 

[nicksr]

yeah Guden-tite is about right. After I went back out to tighten them up, I realized there was no way i was getting my torque wrench in there anyway.

Well all done. Seems to have eliminated my whistle too. But maybe that is more in my head and I just wanted to benefit more from it than just having a slightly cracked muffler

 

[nicksr]

one more question.

I realized i should have bought a new exhaust tail pipe cushion, but didn't. I am going to order one. Will I be able to slide that in without unbolting everything?

The old one split in half when i cut the pipe and the muffler fell to the ground.