Hi all, suddenly developed an exhaust leak today on my

'00OBW, 107k miles, AT, 2.5L N/A, it is coming from the connection between the rear cat and what I guess is the 'resonator'?

 

I haven't checked the service manual yet to see what it says about this repair, but have the following questions:

1. What's the best way to fix this issue?
   
2. How hard is this to fix? Can I just unbolt the flange, slip in a new gasket, and bolt 'er back up?
   
3. Any risks to driving like this for a while? It sounds like I have a glass pack muffler on it. The leak is after both the front and rear o2 sensors.
   

'00OBW, 107k miles, AT, 2.5L N/A

Just had this on my '00 Outback. I bought the bolts (with springs) and the gasket from the dealer, only place that had it but the price wasnt too bad. I had to cut the old bolts and drill the rusted/cooked in parts out of the flange before reinstalling new. After that just clean the connecting parts on the 2 pipes, slip on the new gasket and reconnect. Be careful to tie up the rear half of the exhaust system while you have it apart, or just remove it. I was just fitting the connection together and it dropped and broke the gasket on the midpipe to muffler connection. After replacing that too, it is as quiet as when I bought it.

Great, thanks sidedown, that's what I needed to know. Sounds fairly straightforward. I was wondering about tying up the rear part of the exhaust, since I was kind of surprised to see there is no support from way back by the muffler all the way up until before the rear cat.

Just out of curiosity do you have the P0420 CEL.

Hi cannonball, yes as a matter of fact, a couple days before I could hear the exhaust leak I did get a P0420. I reset it and it hasn't come back (yet!).

i had that same thing happen to me....i ended up cutting off both flanges and welding in a custom steel pipe to sleeve them....good luck....

Hi all, just an update on this issue. Just received the parts today from http://www.subaru-parts-dealer.com. I ordered the gasket, bolts, springs, and nuts. Now to find time to put them in!

how much did they charge u for the bolts,springs, and nuts??

 

i got raped for 22 bucks at the dealership

 

i just got a new(used) cat from, someone and bolted it up a few days ago

let's see...total for exhaust parts $21.40: exhaust gasket $6.16; two flange bolts ttl $4.40; two nuts ttl $3.66; two springs ttl $7.18.

 

I also got two cam cap o-rings $6.12 ttl and starter contact set $5.31.

 

Add on $9.95 shipping (their minimum shipping charge or 10% of order) for total $42.78.

Good prices, that gasket cost me $12.39 at my local dealer. My '99 didn't have those fancy bolts, they were just normal, long bolts (6mm?) with washers and nuts. They may not be the originals. Whatever, it works and doesn't leak.

 

The old gasket was a pain to get off. Whoever worked on it last really crushed it down. I used a cold chisel to cut through it and took it off in pieces.

Thanks for the info ron917. Hopefully mine won't be stuck on too hard. I'd guess it's original. Otherwise I'll have to pull out some of my cheap harbor freight air tools and open a can of whoop-butt, or at least Kroil, on it.

 

Maybe I should get a little lead antisieze to put on the new gasket.

Thanks for the info ron917. Hopefully mine won't be stuck on too hard. I'd guess it's original. Otherwise I'll have to pull out some of my cheap harbor freight air tools and open a can of whoop-butt, or at least Kroil, on it.

 

Maybe I should get a little lead antisieze to put on the new gasket.

 

 

Porc73....did you do the job yet?

not sure...but from the pic, it looks like some metal may be rotten and you might not have enough there to clamp to get a new seal..even with the new gasket

Hi bgambino, nope I haven't gotten to the job yet, it will probably be a month or so. I'm guessing/hoping the rusted out looking section there is actually the old gasket. From looking at it underneath the vehicle that's what it appeared to be to me. But I guess I'll find out when I disconnect the union there. If it is too rusted out I hope it's on the resonator side and not the cat side.

 

My next job is timing belt/water pump/idlers/etc/etc/etc on my '96. I need to tackle the more reliability critical jobs first so I always have at least one reliable vehicle ready to go.

OK finally got this exhaust leak fixed. Glad I bought new bolts since one of them snapped when I was trying to remove it. Also noted the heatshield on the rear cat was loose so I put on a big worm drive clamp. Here's some pics.

Wow it's hard to believe it's been five years already since this repair. I noticed this donut gasket is pretty much rotted out again so it needs another replacement. So far all my soobs have needed this gasket replaced.

 

Do these gaskets contain lead? Something makes them slightly malleable.

Both my 98 and 99 OBWs developed the exact same exhaust problem. I took it to a muffler shop, who torched off the fitting, eliminated the resonator, bent a piece of pipe, welded that in. I was out the door with a cost less then $50. Eliminating the resonator made no difference in exhaust sound. It sounds perfectly like OEM. I don't know why Subaru bothered to use a resonator.

Both my 98 and 99 OBWs developed the exact same exhaust problem. I took it to a muffler shop, who torched off the fitting, eliminated the resonator, bent a piece of pipe, welded that in. I was out the door with a cost less then $50. Eliminating the resonator made no difference in exhaust sound. It sounds perfectly like OEM. I don't know why Subaru bothered to use a resonator.

 

I always have this flexjoint eliminated when it leaks or even looks wimpy and I've posted that here over the years.

 

My local INDEPENDENT place cuts it out, bends a new sleeve (straight section of pipe they expand on their pipe bending machine) and welds it up.

 

40 bucks. Can't beat it. Especially if flanges are rusted the parts basically cost that (2 flange repair kits, donut).

Hm yes that sounds like a more permanent fix! In hindsight having it eliminated does sound like a better longterm solution, esp if can find a place to do it for that price! The donut and new springs/bolts costs about that much anyway not to mention the time to install them and like you say possibly needing one or two split flanges.

 

One issue I've found is for this donut to seal properly, obviously the part of the exhaust the rounded side sits against must be smooth. The old gasket likes to stick there and it takes a lot of chiseling and wire brushing to get it all out. If it's not smooth all the way around it won't seal completely. I just had that happen on '94 Legacy. So as a test I smeared about 3/4 of a tube of permatex ultragrey I had left around the donut, that actually worked very well and sealed up the remaining little leaks.

Edited January 26, 201214 yr by porcupine73

When I used to try and fix these yea - the surfaces needed cleaned well.

 

Still the Walker # for the donut was just too tight. I looked through the donuts at the parts store and would buy one slightly larger that fit better. I used to keep the empty bag here so I had the part#.

 

But get it welded and be done with it.

 

Mine woudl usually happen before/during engine swaps or HG jobs because the joint is wimpy. So I didn't have to worry abotu exhaust being in the way when removing or installing the engine. But I did have to yank a few engines after this welded repair and found the exhaust not any more annoying to work around.

I will keep that in mind for next time. I think I don't mind the donut so much as long as the flanges are still intact, but after that it becomes a lot more work messing with the split flanges, getting long stainless bolts which are a couple $ each and stuff like that.

 

The Subaru exhaust pipes themselves seem to be pretty good quality. Even on my 94 and 96 rust bucket soobs, the exhaust pipes don't seem anywhere near rusting through. Unlike the brake lines, fuel filler neck, and stuff like that.