tommy boy2

gonna try to change out the resonator pipe where it connects to the cat on A 1994 civic hatch - the schematic does not say which bolts to use (and nuts and washers) to connect the new resonator pipe to the cat (the 3-hole flange connector).

Also: any good/easy way to disconnect old rusty parts here?
thanks!

tommy boy2

wrong pic but to illustrate the point: between the resonator and the converter, mine also have this 3 sided-flange and gasket with 31383 gasket - what bolts should i pick up assuming i can get it off??
thanks!
http://www.carid.com/images/walker/e...cheme/0273.jpg

tommy boy2

ejv8s10

I use a cutoff wheel on my angle grinder or die grinder. It is very easy to cut a bolt without damaging the exhaust pipe.

B serious

iTrader: (1)

Impact or breaker bar. If they don't turn...they'll snap, which is more convenient anyway. Air hammer them out of the cat body.

Its easier to access the top bolts if you remove the 2 spring loaded cat-to-down pipe bolts first. Then unhook the first 2 exhaust hangers near the resonator. It'll droop down. You can get medieval on its ***.

I replace them with stainless hardware and use anti sieze on the threads.

tommy boy2

thanks - i was thinking of just removing the resonator and leavin the cat in place and then attaching the new resonator and muffler onto that- i figure less unbolting and bolting that way - make sense? and should i attach the new resonator to the new muffler before putting them onto the car/cat? is it easier to do it that way 1st? thanks!

tommy boy2

sounds like air tools would help too:
do you think any mechanic would just do this hard part - taking the bolts off the old cat/resonator and leave me to install the gaskets and parts? I was quoted $650 by a shop to do a cat back (boston prices) and i already have a muffler and can get the resonator pipe and gasket from autozone for $100 or so, so I figure i'd come out way ahead (and much quieter too), but I'm not sure I can get those rusted nuts off...

belairbrian

I normally use grade 5 steel bolts and brass nuts.

As for removal, I'm in the snap em off with a couple of breaker bars and 6 point sockets camp. If they round off then I grab a cutoff wheel.

tommy boy2

where can i get grade 5 steel bolts and brass nuts? and what size do I need too? thanks.

my local junkyard said they work on cars too and would let me supply the parts so I have a fall back after I try to twist off the bolts. might try to wait for a warmer day (33 or so today - brrrrrr)

B serious

iTrader: (1)

The factory bolts are metric...and they're class 10.9, which is much stronger than a standard grade 5 bolt.

A G5 bolt will work anyway. But...I'm not sure why one would not just get stainless bolts.

Anyway, they're M10x1.25 bolts/nuts from the factory.

The equivalent English size would be maybe 3/8 - 16 or something.

Not sure what length. Off the top of my head, 1.5 - 2" (or 35 - 50mm if you're going metric).

Use the sizing above. Buy stainless, G5, english, 10.9 metric, brass, titanium, grape jelly, or whatever material/designation you decide.

tommy boy2

gonna try today - so I need 2 breaker bars forbolt and nut? Will 1/4 drive be too weak? gonna try to get some new bolts and washers and nuts and anti-sieze stuff (will the small packet the sell by the register be sufficient?) thanks!

B serious

iTrader: (1)

Yes. 1/4" drive is too small. You need a long, and 1/2" drive or larger breaker bar.

tommy boy2

any idea what size the nuts and bolts are - I may need to borrow the 1/2 inch drive and sockets. And do I need to be careful not to damage the cat when I try to remove the resonator and back? its pretty rusted through - I could cut part of the back pipe off it would make it easier to remove too

tommy boy2

and where do I get the number 5 bolts: hardware store? or auto parts store? and d does anyone know if i can do this with a jack and a jack stand or does it need more clearance, like on a lift? thanks!

B serious

iTrader: (1)

The stock bolts have a 14mm head. Hardware or auto parts store for bolts. Idk how high up your jack and stands go or how much your belly sticks out.

tommy boy2

i've got the smallest sears special floor jack, doesn't raise it up too much, especially when you jack from the side, so maybe a foot or a foot and a half of clearance underneath and belly=medium. i am thinking not enough to get the torque to pop or turn them off... And i need 2 breaker bars to break them, right? one to hold the nut and the other to crank the bolt head? Do I need to be careful not to damage anything when cranking? thanks again

tommy boy2

picked up some bolts and nuts at autozone: 30mm long - and they are grade 10 and 10.9 - they didn't have anything else really. The guy said they will last forever. $6 for 4 of each.

B serious

iTrader: (1)

That's the rating of most of the stock bolts on the car. I believe the cat has studs in it. So you won't need 2 breaker bars.

What size diameter and thread are the bolts you bought?

You'd know better than us if your jack goes high enough.