Leaky exhaust joint coupling

HBV850 · Post by **HBV850** » 17 Apr 2008, 09:14

Greetings all! New to this forum and I have an exhaust problem I'm hoping to get some advice on to remedy.

I replaced the whole exhaust on our '95 850 wagon (105K mi) about a year ago with a standard replacement unit (nothing fancy). I keep getting an exhaust leak right at the ball and flange coupling in the middle where the front pipe joins the rear, and was wondering if anyone has has similar issues and/or has any ideas for a permanent fix?

All the mounts are in good shape so I don't think it's due to excess flexing. It seems to just be a pressure fit (clamp squeezes the rounded ball part into the flange of the other pipe) unless I'm missing a gasket that's supposed to go in there? The only other thing I can think of is maybe the aftermarket clamp that's supposed to squeeze the two together is weaker than the factory clamp and isn't doing its job properly? My CEL light came on again yesterday and I'm hoping this is the reason.

Thanks in advance for any ideas or suggestions!

Post by **Ozark Lee** » 17 Apr 2008, 11:00

I looked it up in VADIS and it doesn't show a gasket or a doughnut at that joint.

The OEM part numbers are 6842851 for the upper clamp, 6842852 for the lower clamp, 946440 for the bolts and 945408 for the flange nut. You obviously need 2 of the nuts and bolts. So long as the new exhaust system is the same diameter as the original the new clamp will likely fix the problem.

As far as the CEL goes pull the codes from port A-2 and it will tell you what the car is mad about. Since that exhaust joint is behind the rear O2 sensor I doubt that the leak is the cause.

...Lee

HBV850 · Post by **HBV850** » 17 Apr 2008, 13:03

Thanks for the reply Lee. I downloaded and took a look in the Haynes manual for the 850, and it appears the OEM clamp is significantly wider than the aftermarket clamp I have on there now. So it's worth picking one of those up at the dealer to try it.

I'll check the trouble codes and let you know. I just had a long go round with aftermarket O2 sensors causing problems and installed factory Bosch sensors front and rear a few mo's back. I'm going to cringe if the code points to either sensor yet again! I thought I remembered reading somewhere that a leak in the exhaust could cause a code to set, but maybe I'm just trying to stay optimistic?!?!