Catalytic converter fell apart internally - it rattles!

[savage1987]

I was laughing at Cogez's VP Calais the other day because when you rev it to about 3000rpm, hold it, then let go, you get an odd-sounding rattle from the catalytic converter. Sounds horrible.

The other day I realised, to my embarrassment, that my VN has the same problem! It's just harder to hear mine because I have a 2.5" with just one muffler, no resonator, while he's got a pretty standard system on his.

I've been quoted $270 for instal of a new converter, or $100 for a second hand one . . . is this reasonable? Considering the fact that I'll be getting Pacemaker extractors in the future (possibly soon) should I get a different type or size? I've heard the ones from the VT/VX commodores flow really well - would it be simple enough to fit one of those instead?

Cheers guys
Sam

[savage1987]

We picked up a second-hand one ($100) for Cogez's VP today. Bolted it up but having the same rattle problem. Do ALL VN/VPs have this problem?? What else could be causing this rattle? Something in the engine itself that just SOUNDS like it's coming from the exhaust??

Or is it probably just because the second-hand one was just as rooted as the original one??

PS The 3800 block has a wicked crackle if you run it with the exhaust unbolted at the end of the headers (couldn't resist :P)

[90VN55]

well i took my exhaust off and i found that my muffler was full of rust.
it could be that rattling and not the cat

[Morton]

I have a good vn/p cat sitting in the garage. Shame you live in Canberra. You should be able to pick one up from a good wrecker for $50-60.

[greenfoam]

My wrecker charges 30-40$ as that's what the metal guys pay for them

[savage1987]

But a second-hand one from a VP or whatever will be just as old = worn as the current one . . .

The rusted muffler issue - maybe on Cogez's, but my system is less than 12 months old from the cat back.
hmmm . . .

[xcop5l]

before you put the cat on give it a shake if it rattels dont use it
go over your mufflers and give them a bash with your fist if there rooted they will rattel

[greenfoam]

But a second-hand one from a VP or whatever will be just as old = worn as the current one . . .

The rusted muffler issue - maybe on Cogez's, but my system is less than 12 months old from the cat back.
hmmm . . .

A dead one can be empty inside! ie noooooothing in it.

If you hold the cat up to the light you can see right though, if it looks all kinda tripy but all even like a flies eyesight then its ok , you can get rattles in the cover of them with out the wires inside being broken

[savage1987]

Neither one rattled when shook. I'll give the mufflers a bash and see what happens. Doesn't explain my rattle though . . . maybe mine's a cat and his is a muffler

[Shortstuff]

My tailpipe trim rattles at low revs. It drives me mad - sounds like the exhaust is rubbing on the underside of the car.

[anton1o]

Ive got a gay rattle 2, i fixed it by shoving a nice chunk of rubber right at the end where it holds the exaust/tip up..

Altho that doesnt seem to be doing the job for too long as im rattling again! 2.5" Exaust here i come

[mouce]

Sometimes when the cat collapses internally, little chunks of the honeycomb can end up in the pipes. I had to take my entire system off to empty out the bits and pieces when my cat got blown apart.

[savage1987]

'little chunks of the honeycomb can end up in the pipes' . . . oh dear. might give cleaning them out a go, although I'd imagine I need a hoist for that one . . . hmm.

[90VN55]

a hoist would help.
but i just put my catback exhaust on with only one side up on ramps. so it would be easier taking one off

[VLCrewman]

How'd you manage to blow ur cat up? I stuffed mine by launching an exhaust turbine off a turbo thru it!, but yeah, not fun finding the bits and peices in the pipework. If your lucky, u'll probly find the pipe is sectionalised, so u can take one bit off and shake it out, and put another on and so on and so forth.

[savage1987]

I think mine's just falling apart from age and a bit of hard work . . . either way, I'll have a 2.5" one put on with my extractors later on. I'm just trying to figure out why Cogez's car has a rattle . . .

[mouce]

I replaced the front muffler section of pipe and I had nothing more than 1 standard VN commodore jack and one axle stand. It took me an entire afternoon to do it, but you can drop it off and bolt it back up with only the rear passengers wheel lifted.

[anton1o]

Anybody know of good Cats for vn's?

Ive heard the VY SS Cat's are good enough for a VN6 with even more then moderate mods

[savage1987]

mm I've heard something along those lines as well . . .

[Cogez]

With regards to rattling exhaust problem, I replaced my cat, then all the exhaust from the catalytic converter back, and it STILL rattles.

**** knows what's wrong with it, I may jump out my window.

[Not_An_Abba_Fan]

Check all the bolts holding your extractors, if they come loose it will sound like a rattling cat.
Is it an auto? Check the torque converter bolts where it bolts to the flywheel.

[savage1987]

Damn. I just learned to ignore mine. Btw Cogez, if you come over with ur car for Christmas I've found someone who can get Pacemakers at trade price for us. $450 supply only. not bad, hey?

Torque converter.. ours are both auto, surely after the punishment mine's taken it'd be blown by now if those bolts were loose!

[Zuicider]

hehe i had the same problem, rattling coming from the cat and mega loss of power, ended up being a shot muffler

[savage1987]

i got no power loss that i've noticed. having said that, my engine's making so many top end noises that i don't know what's normal any more.

[S Pack]

i put a 3" high flow cat in mine.......fixed my rattle as my old one was rooted and improved exhaust note. Also stopped weird smells from using premium fuels.