exhaust reverse flow

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oppositeLock
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exhaust reverse flow

Post by oppositeLock »

Has anyone had an issue with the exhaust flowing back to the passenger compartment from the tailpipe exit? Even on a half hour drive (top down) with very few stops I get back smelling like exhaust. I'm pretty sure my exhaust is free of leaks - new gaskets at the block and header collector so I think it's pretty well sealed....though even if not, I'd think it would be ducted away when moving, unless there's an aerodynamic back flow.
'68 R16 + 5spd
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GeoffM
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Re: exhaust reverse flow

Post by GeoffM »

That's the smell of VICTORY!
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oppositeLock
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Re: exhaust reverse flow

Post by oppositeLock »

Correction. Leak at (and potentially through the sides of) the flex pipe. Back to the exhaust shop.

But while I'm at (hijacking my own thread :D ) do the flex pipes typically seal well through the woven part?
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Gregs672000
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Re: exhaust reverse flow

Post by Gregs672000 »

They have a tube through them, the mesh allows for flex.
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oppositeLock
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Re: exhaust reverse flow

Post by oppositeLock »

Back at this. Exhaust shop checked everything and says it's sealed.

So is backflow from the tailpipe exit to the "cabin" area while moving a common issue? (driving with the top down btw).
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greydog
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Re: exhaust reverse flow

Post by greydog »

Not on my high windshield cars. At a light, yes but once moving no.
Try this, get a cheap exhaust extension. See if extending the outlet makes a diffference.
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Alvin
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Re: exhaust reverse flow

Post by Alvin »

greydog wrote: Fri May 25, 2018 10:52 pm See if extending the outlet makes a diffference.
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oppositeLock
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Re: exhaust reverse flow

Post by oppositeLock »

It's definitely bad at a light, but even driving for a half hour with very few stops I smell like exhaust when I get out. cough.
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Alvin
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Re: exhaust reverse flow

Post by Alvin »

oppositeLock wrote: Sat May 26, 2018 12:03 am It's definitely bad at a light, but even driving for a half hour with very few stops I smell like exhaust when I get out. cough.
I really think that is a result of running rich, Joe.
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boxcar
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Re: exhaust reverse flow

Post by boxcar »

I'd have to agree with Alvin on this one.
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nismou20
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Re: exhaust reverse flow

Post by nismou20 »

Exhaust smell or Blowby smell? Is your aircleaner to valve cover hose properly attached?
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oppositeLock
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Re: exhaust reverse flow

Post by oppositeLock »

Yes, do have the hose and air cleaner attached. As Alvin points out, idling at stop it's definitely made worse by the rich mixture (working on solving that) but I'm convinced there's exhaust working its way in there at speed.
'68 R16 + 5spd
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