Strong exhaust smell everywhere?

[kfbmx]

I am having a problem with a very strong exhaust smell throughout our MCI-8.  While driving, smelly exhaust laced air pours out of of the ducts if the Bus Air is not turned on.  It also pours out of any opening from the bus into the center wire tray.  I do not see an obvious opening between the engine compartment and the center wire tray, but that is definitely where the smell is originating.  I have a small exhaust leak on the manifold and I understand why the engine compartment smell of exhaust, but why is it literally blowing out of the duct?

I was thinking of sealing up the wire tray with tray with something like Great Stuff.  Is the airflow though this duct necessary or could I plug the airflow?

[Nick Badame Refrig/ACC]

Welcome kfbmx!

There is a return duct, both sides,  just rear of the bulkhead over your drive wheels. It is made of plastic and could have cracked.

This maybe your scource of exhaust smell.

I hope you find it, CO is the deadly killer....

Good Luck
Nick-

[kfbmx]

Could someone post of picture or a diagram of the duct you are talking about?  I have the MCI-8 CD and I will try to look at the exploded views.

[gus]

The air duct leak is the symptom, the exhaust manifold leak is the problem.

An exhaust manifold leak will only get larger and needs to be fixed unless you want an even bigger expense soon. The high velocity exhaust gases are like a cutting torch and will cut grooves in both the block and exhaust manifold.

[Nick Badame Refrig/ACC]

Hi kfbmx,

Gus is right, I would also take care of the manifold leak first...

Nick-

[FloridaCliff]

Hi KFBMX,

The exhaust gases are nothing to mess with!

Trust ME, I KNOW....

http://www.busconversions.com/bbs/index.php?topic=1218.0

Get it fixed!

Cliff

[kfbmx]

I promise that will be getting the leak checked very soon. That will need to be done by a shop but I can do the duct stuff myself and I do not want ANY smells from the engine compartment blowing back up the ducts into the coach.  I have a few days and I would like to try to close up this leak. Plus, I do not think my wife will travel in the bus again until I get the mess fixed.  None of my CO2 sensors (3 of them) are going off, just a overwhelming engine smell and blowing out holes that should not be blowing anything.

[chris4905]

For years we got engine "exhaust soot" inside the bedroom of our 4905.  I always though it was just coming from the engine compartment due to the bedroom area having a non sealed joint somewhere back to the engine compartment.

I'm now doing an engine swap and upon taking out the old engine, I discovered one of the exhaust manifold pipes, going to one of the entry ducts into the muffler, had broken off at the side of the muffler.  So all the exhaust from this exhaust line wasn't making it into the muffler, and out the tailpipe, it was being lost within the doghouse area and some of it of course making it's way into the bedroom.

It was almost impossible to see with the engine still in the bus, and I never noticed any noise such as exhaust leaking.  I have removed the old muffler;, thrown it away, and will be putting in a new muffler in a different location.

[gus]

When I smell exhaust in the bedroom of my 4104 I know something is leaking in the exhaust system. When the system is intact all the smell goes out the back through the tail pipes.

I've had a tailpipe come loose (Twice) at the bottom of the muffler and holes burned/rusted at the top of the mufflers. This is about 8" from the bedroom shelf floor.

This exhaust smell in the bedroom does not make the wife happy!!