Exhaust System Leak

[landy]

In attempting to reduce the smell of exhaust fumes in the cab of my 710M, I found a small hole in the muffler and am thinking about trying an E.I. muffler.

I can feel a relatively strong leak around where the individual header pipes are welded together, before they go into the two small pipes that go to the heat exchanger. Don't feel any leaks around the pipe joints.

I can't tell if the leak is coming from the manifold pipes themselves due to a hole or from where the pipes attach to the exhaust ports. I don't see any visible evidence of holes in the header pipes, so perhaps it's leaking at the exhaust manifold and port surface? How common are leaks there - failed exhaust manifold gasket? I suspect it's a real PITA to get the bolts/studs off to replace the gaskets?

Thanks and happy holidays!

[pcolette]

I have one of EI's mufflers and they're really nice. Very well made and a slightly deeper tone. Definitely a thumbs up!

Due to all the cooling turbulence, etc. I've found it hard to pinpoint exhaust leaks in the area you're referring to. I have found leaks typically in 2 places:
1) the short pipes from the headers to the heat exchanger have steel sealing rings in them which over time seem to develop leaks. Also if the pipes are not aligned well, as level as possible, they can leak around the rings. I've replaced them with the flex exhaust kit on both of mine.
2) where the 2 rectangular flanges meet there is a gasket sandwiched in there which degrades after a while and begins to leak. Replacing it can be a knuckle buster but is not as difficult as it looks. You'll need new bolts & nuts.

[kpoling]

X 2 on the EI muffler. Bolted right up, very well made!

[landy]

I thought I might upgrade to that flex kit, too, in the hope of eliminating other potential leaks, but read that depending on which vendor you purchase it from, there may be some fitment problems. Any comments on that?

[pcolette]

The only flex kit I know of on the market is from SAV. It fits fine and is great quality but there is some modification of the headers needed (grinding off a welded on steel flange on each - see photo). Or you could take your Pinz and the kit to a good muffler shop and it can be welded in place on the header end.

header.jpg

[Jimm391730]

but there is some modification of the headers needed (grinding off a welded on steel flange on each - see photo).

Both my trucks have a flex coupling and one has EI's stainless muffler (another thumbs up for it), but I have not had to remove the flange from the end of the headers as I felt there was enough pipe sticking out through the flange to clamp the flex coupling to. YMMV but I've yet to have a problem with the flex coupling or the install, and I have about 10 years combined time with them.

[landy]

Just ordered a muffler from EI. How are owners routing the exit tailpipe? Mine currently exits in front of the rear tire, which seems likely to contribute to exhaust fumes in the cab and back. Perhaps behind the rear tire with a slight turn down or out the back?

Thanks!

[pcolette]

EI's muffler is designed just like the stock unit so there isn't really an easy way to change the routing of the tailpipe. It's possible but would require some bending, etc.
The muffler actually exits towards the front of the Pinz and then is turned by the tailpipe.

pzmuff.jpg

[landy]

So if you have the stock EI muffler tailpipe configuration, any problems with exhaust fumes in the cab or back?

I was also considering taking it to a muffler shop and adding some pipe with appropriate bends to reroute the exit to the rear.

[pcolette]

I had mostly eliminated the exhaust fumes prior to the new muffler by having the carbs rebuilt/adjusted/synced by Jim L. and by adjusting the valves and timing. I rarely notice any exhaust odors now.

[audiocontr]

I did not push the EI exhaust, and heat exchanger far enough forward when I swapped the exhaust. Now I have a leak at the stock flex coupler. Have you tried loosening the system and pressing it forward, then retorquing?

[pinzinator]

Here's how I routed my tailpipe, and it works well-



Also, my 710 arrived from Europe with the flex coupling already installed in 2003.

[landy]

That looks nice. No problem with exhaust fumes entering the back area?

[TechMOGogy]

That is a great picture and it is good to know that the stock muffler can still be used when rerouting towards the rear.
Thanks for sharing that shot

[pinzinator]

I used to get an occasional reminder of the Pinz exhaust, but it was rare and only under ideal conditions, such as speed and wind direction. The aerodynamics (or lack thereof) of the Pinzgauer contribute to the exhaust issue as much as anything. With the new ignition system installed the exhaust smell is almost non-existent.