Exhaust replacement help

[s2cmpugh]

Good day everyone. I'm replacing my exhaust and catalytic converter in a few weeks, but need some suggestions on how to remove these fasteners.

My catalytic converter will be a direct fit (magnaflow OEM style) and the rest of my exhaust will also be a direct fit replacement (magnaflow cat-back).

I see three fasteners that attach the cat. to the downpipe, but are those fasteners bolts and nuts OR studs and nuts (similiar to a hub)? Also, I'm supposed to resuse those fasteners, but how if they are studs welded on the OEM cat and the magnaflow cat does not have any bolts or studs??

Would it be easier to drop the whole system from downpipe back?

If I need to find replacement fasteners, what size should I be looking for (stainless steel is a must)?

Any help with details on how this stuff is fastened together (bolts, nuts, etc.) and the easiest way to get it off would be greatly appreciated!

Cris P.

[BurtonRiderT6]

Easiest way to get them free would be to use some PB blaster. If that isn't budging it then get out the Mapp gas or propane bottle and throw some heat to it. Just be careful not to burn yourself.

They are bolts and nuts, I don't know the size of the bolts but if you know the diameter of the holes in the flanges then you can go to the local hardware store and ask for a bolt and nut capable of withstanding some heat. I would prefer to use fresh nuts and bolts, maybe spend $5 on new hardware. That's me though. If you're strapped for cash you can re-use so long as you didn't strip/damage them. Good Luck.

I would not drop the system, otherwise it will be harder since you have nothing holding it in place as you try to take it apart.

[s2cmpugh]

I actually PB blasted them yesterday just to get a head start on things. I was able to loosen the muffler to resonator bolts (pretty rusty), but I only tried a little on the cat to down-pipe buts. Both nuts are 14mm.

I don't mind dropping the whole exhaust as the down-pipe has been previously disconnected from the header when I replaced the oil pan and gasket. As a result, I know those bolts are able to be removed, especially since I applied anti-seize.

I just didn't know if people thought the job came out easier with the whole system removed or still on the car. That said, working on it in the yard really would create a WHOLE lot of space for tools and stuff.

Maybe I'll swing by Lowes and scoop up some 14mm stainless bolts and washers just in case.

[toycar]

These bolts are often a bitch to get out.


Personally, i dont even fuck with trying to remove them on the cat. Usually the rest of them are workable, but the cat tends to lock them into place over time due to the heat and it is a BITCH to remove them.


I cut them off, heat the flange with acetylene torch, and use an air hammer to smash them out. Its super easy with the right tools.

Takes me about 10 minutes to remove all bolts on cat.

If they fight you, and it gets frustrating call around and find an exhaust shop that will do exactly what I said for you. Prolly cost 20-25 bux for them to do it. You can limp the car home with an open DP, just DO NOT DRIVE IT HARD AT ALL. Its not safe for long term driving, but for a 5-10 miles cruise home it'll be fine as long as your not allowing the car to rev to high. Keep it under 3k rpm's.

Get grade 8 bolts from your hardware store/parts store for replacement. Honda OEM uses M8 bolts(grade 8) for the exhaust. Should cost less then 10 bux for all new hardware.

Hope that helps!!

[Dr. Shuffles]

If they fight you, and it gets frustrating call around and find an exhaust shop that will do exactly what I said for you. Prolly cost 20-25 bux for them to do it.

If you do that, might as well just spend another $20 to have the shop install the whole thing.

[toycar]

If you do that, might as well just spend another $20 to have the shop install the whole thing.

If they will do that for that money then yeah, I agree 100%.

In my experiences its alot more expensive though. Usually 75-100 bux. Shops charge around $90/hour, and it takes a while to get the exhaust hangers swapped out and the new exhaust installed. Usually an hour, to 90 minutes.


But yeah, if they will install an entire exhaust system that you didnt buy from them for $20, do it. Thats a steal.

Around here, that would never happen. Most places in Omaha will not touch an exhaust for install that they did not sell.


Im sure it varies from city to city.


Op;

Call around and see what available. Doesnt hurt to ask yanno?

[Dr. Shuffles]

When I got my car, it needed a new catback. I was fully prepared to put it on myself. I crawled under there, got a good look at the catalytic flange, and realized there's no way I'd get that rusty mess loose with the tools that I had. So I took it to a shop, and had them install it - I think it cost $40 or $50.

[s2cmpugh]

Luckily the bolts for the cat to downpipe flange don't appear to be very rusty, so I'm hoping I can just remove them myself.

If worst comes to worst I will take it somewhere, but I'd prefer to at least try it and see if I'm successful.

Will removing the whole system make things easier though? That's my main question.

[brutalcb7]

Will removing the whole system make things easier though? That's my main question.

For me removing the whole system would be unneeded extra work, unless your main concern is work space, which you'd have to decide for yourself. really the only problems you would run into, is if you strip anything out and cant remove it yourself, go to your hardware store and get your replacement bolts, pb blast the bolts on the cat, let it sit for 15-20 minutes and go at it. and with the replacement bolts you wont have to worry about breaking the bolts at all, which will probably happen even with the PB. good luck man

[s2cmpugh]

For me removing the whole system would be unneeded extra work, unless your main concern is work space, which you'd have to decide for yourself. really the only problems you would run into, is if you strip anything out and cant remove it yourself, go to your hardware store and get your replacement bolts, pb blast the bolts on the cat, let it sit for 15-20 minutes and go at it. and with the replacement bolts you wont have to worry about breaking the bolts at all, which will probably happen even with the PB. good luck man

Thanks man! Work space is my main concern as laying on my back looking up, trying to loosen tight bolts, and having crap fall in my face isn't my idea of fun. Since I'm replacing all the bolts anyway, it might help me out if they did break! And, if I can't get them loose with my wrench, this gives me a good excuse to go buy a reciprocating saw!

I stopped by Lowes this morning and they did keep in stock some M8 stainless steel bolts and nuts. Of course, I'll load up the anti-seize on the hardware to help ease in removal down the road.

[s2cmpugh]

I ended up dropping everything from the header/downpipe on back. This made removing and seperating things MUCH easier. New cat. and exhaust system is installed!

Video (please pardon the poor camera work, I never claimed to be Michael Bay)