r_kage

Hello--I took my 1995 Honda Accord EX in for inspection and learned that the resonator/intermediate pipe is leaking. I suspected there was some kind of leak, but thought it was at the connections rather than at the FLEX portion of the flex pipe. I didn't expect a problem with the pipe as it was installed 1 1/2 years ago, and the car hasn't been driven more than 10,000 miles.

I DID expect a leak at the connections, however, as I was working in limited space when it was near 0 deg F in an unheated garage, and reused a couple of the old gaskets. I planned to replace them properly when the weather warmed... but I didn't get around to it.

ANYHOW, I called a local, trusted muffler shop to see if they'd weld a new flex pipe section in and when they quoted me $180 (give or take a little), I ordered another Bosal flex pipe, and figured I'll either put it in myself or have the shop do it, and replace those gaskets while I'm at it.

Many people seem to be having problems with the Bosal resonator, but when I looked at the Walker, I saw that many people also seemed to be having problems with those as well, and since I didn't want to risk differences in connecting parts, I'd just order the same ol' Bosal part, reluctantly!! Anyhow, I started to wonder,are all these simply defective? or .... Are there certain steps that DIY people commonly (not just myself) neglect or fail to consider when installing a new exhaust?

I'm thinking out loud here, and hoping ultimately that this will help someone along the way if their exhaust seems to fail prematurely.

1) When I called the muffler shop, I was told that the flex pipe shouldn't have worn out so fast, and suggests that there is excess vibration--maybe broken motor mounts or something. I don't think that's the case with my vehicle, but might be relevant to someone.

2) Similarly--might be relevant, bad suspension parts could also cause jolts and vibrations, that could ruin the flex portion.

2) Elsewhere on Honda Tech, I saw this discussion: https://honda-tech.com/forums/honda-...stall-2953451/ which said that Honda didn't use a flex pipe, but instead absorbed vibrations through how the exhaust is mounted. I found that interesting, since the flex pipe is supposed to help absorb vibrations. {I'd love the parts numbers for those mounting bolts--might head over to Honda to get them!} So it then dawned on me: While I seemingly ordered the entire Bosal cat-back system, there were no parts numbers for where the mid pipe attached to the catalytic converter, so I used STANDARD BOLTS. This was likely a mistake and quite possibly (I'm just theorizing) why my flex pipe is now leaking.

3) Of course, it could be also that the Bosal exhaust is just substandard and defective, in which case, say, a factory exhaust (or other brand--can't seem to find a good, reliable brand based on ratings alone) can handle above adverse conditions so much better that I should aim to replace this whole thing by the end of next year!

Have any of you experienced premature wearing of exhaust components? Did you figure out why? Please share!

holmesnmanny

where exactly is the leak ?

r_kage

The mechanic said it's coming out of that area where the resonator pipe has a flexible segment covered by that braided metal.

holmesnmanny

seafoam it and test for yourself if its leaking, he may be trying to run you

r_kage

Nah, he was suggesting I take it to another shop to get a new segment welded in rather than they replace the part. The reviews on both the Walker and the Bosal resonators are pretty abysmal and I was just trying to determine if it's just that these companies don't know how to make the parts, or if people installing them are overlooking something. Or something else altogether different. For example: I called a muffler shop and was told that maybe the motor mounts are bad, causing vibration and thereby ruining the flex pipe. I know that's not an issue with my car, but hey, maybe there's something else I (and other DIYers) overlook when installing this piece. If so, I'd like to know so that I can fix whatever it is and know that the parts will last longer. If not, no harm in asking I would hope.

r_kage

Oh, but I will double check to make sure that it is the flex pipe and not the nearby joint that is leaking and try out that seafoam trick.

GhostAccord

Had a Bosal B pipe w/resonator and axle back muffler installed on my 96 accord for 10 years without any issues.

When you say flex pipe what are you referring to? The flex joint in the OEM exhaust is a ball and socket joint located just after where the exhaust down pipe is mounted to the engine block. If you have an aftermarket braided steel/corrugated flex joint installed, it could fail pretty quick in that location. Even with new engine mounts that part of the exhaust moves quite a bit. The exhaust on these cars is held up tight and snug to the chassis. There fore all of the up and down engine movement is taken up by that ball and socket joint. I have seen quite a few aftermarket header down pipes w/braided flex joints fail in this location for that reason.

As far as a resonator failing prematurely;

Premature exhaust failures that I have seen are most often due to one or more of the following;
• Improper installation
• Excessive movement
• Excessive moisture
• Poor quality materials

Do you take a lot of short trips? This can really speed up the corrosion of the exhaust from the inside out. Short trips build up a lot of condensation and do not allow for the pipes to get hot enough to completely remove the moisture. Then when you shut your engine of the mixture of water and hydrocarbons sits in any low spots in the exhaust system, accelerating the oxidation process (rust holes).

r_kage

GhostAccord--Thank you--that's really the type of information I'm after, and you are right, I was referring to that braided flex portion of the long pipe.

Most of my trips are under 15 miles, so that's a pretty interesting observation. Do you suppose internal exhaust coatings are beneficial or gimmicky? Does the OEM pipe last long enough to justify it's extra cost? I paid $85 including shipping for the resonator (would have been less if I were willing to wait a week), and if a coating helps prolong its life, I'd consider doing that, but if this flex portion is doomed to fail regardless, then maybe I should just go get the OEM part and be done.

r_kage

I didn't end up bothering with seafoam. Instead, I sprayed soapy water at a couple of connection points as well as the braided flex area and blew air into the tailpipe and sure enough, the resonator is leaking at the flex area.