[mshriver]

Hello everyone. Ive been doing some searching but can not find the answer. My Mom's 01 outback H6 exhaust has a rust hole in the exhaust near where the midpipe meets the axleback. I need to get some supplies to fix it.

Does anyone know what the factory exhaust pipe diameter is?

Thanks in advance!

 

[lockmedic]

Most muffler shops will fix that for $50 or less. . . why bother trying to fix it yourself?

 

[CNY_Dave]

It is double-wall pipe, that's why it necks down for that joint.

That joint 'wore out' on mine, I ground down the flanges (what was left of them) and used a short piece of 2-inch pipe over the whole joint.

I had to grind down the weld on the inside of the pipe, 2.25 inch pipe would be a lot easier, but you'd have to really crank down on the clamps.

2.25-inch flex pipe might be the best easy choice.

 

[cardoc]

Most muffler shops will fix that for $50 or less. . . why bother trying to fix it yourself?

Plus a warranty if it leaks again due to poor weld.

 

[mshriver]

Most muffler shops will fix that for $50 or less. . . why bother trying to fix it yourself?

Because a relative who welds every day offered to do the welding for me for free. Plus we can easily get it done on a Saturday rather than having my mother go through the hastle of dropping it off at a shop. Why pay $50 and hastle with dropping off a car and picking it up, when it could be done on a weekend for a few dollars worth of pipe.

It is double-wall pipe, that's why it necks down for that joint.

That joint 'wore out' on mine, I ground down the flanges (what was left of them) and used a short piece of 2-inch pipe over the whole joint.

I had to grind down the weld on the inside of the pipe, 2.25 inch pipe would be a lot easier, but you'd have to really crank down on the clamps.

2.25-inch flex pipe might be the best easy choice.

Thanks for the info :29:. I was also thinking a flex pipe would be a good idea in that area. But is 2.25 the same diameter as the factory pipe?

 

[CNY_Dave]

The factory pipe is 2-inch outside-diameter. Flex pipe is avail in different sizes.

Flex-pipe doesn't last long, though.

 

[CNY_Dave]

Crap, it's not 2, it's almost 2.5.

2.5 inside-diameter pipe would be easiest.

 

[idosubaru]

Crap, it's not 2, it's almost 2.5.

2.5 inside-diameter pipe would be easiest.

i bought 2.5" pipe and it was too big for the exhaust on my 2002 H6 and 2003 H6, both of which seem original.

so i think the larger diameter is 2.25" by the muffler-midpipe connector.

 

[idosubaru]

Flex-pipe doesn't last long, though.

by flex pipe do you mean the cheapy stuff they sell in autoparts stores off the shelf? that stuff is like a matter of months.

or do you mean the stainless steel short section you can get on ebay and other vendors? i've never used this type:
2 25" Sus 304 Stainless Steel Flex Pipe Exhaust 6" | eBay

they are said to be not intended for any bends...only for vibration and flex/give to protect components. i'm going to try one on a very slight bend and see how long it gives me.

 

[CNY_Dave]

The cheap stuff, due to rust, so stainless should work.

 

[idosubaru]

The cheap stuff, due to rust, so stainless should work.

that cheap stuff is amazingly flimsy and horrid.

no idea the linked style are any better. i doubt i can get it to fit since i have an ever so slight bend, i cut too much pipe with the flange...GRRRRR!*($!$$

this is our other H6, i don't need this one jacked up with the trans issues of the other one i talked to you about!

 

[CNY_Dave]

Slightly oversize on tjhe pipe will hide a multitude of sins (bends).

 

[idosubaru]

Slightly oversize on tjhe pipe will hide a multitude of sins (bends).

LOL. indeed, really? get a bigger pipe, clamp it down?

like 2.5" on 2.25" or not that oversize?

 

[CNY_Dave]

Yes, just clamp the heck out of the bugger. 2.5 might be a lot of squishing for a clamp.
If I need to I can heat the pipe with my acetylene torch and squish it any arbitrary amount. A good propane torch or MAPP torch might do it.

Cheap pipe you can clamp down quite far, good stuff from NAPA not so much.

You need to use the heavy-duty clamps that have the little buttress where the nut pushes.

If you can orient the pipe clamp so it follows the 'fat part of the curve' you don't need to crank it quite so far. The exhaust sealant stuff could be applied where the clamp is going to go to help insure a good seal, but a small leak there isn't a big deal to my mind as long as it doesn't blow on the diff, u-joint, or CV joint.


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