diesel exhaust smell

[Ducati]

Was wondering if anyone has had a slight diesel exhaust smell in the aft BR. My wife noticed it while we where on a trip. The engine access is right there by the bed and it looks like maybe soot around the hatch area.

[Jim_HiTek]

That sort of points to a muffler and exhaust pipes perhaps have rusted through. Check that first. But you shouldn't have any exhaust drifting into the space under the bed so that hatch seal needs to be replaced. Both of the RV's with diesels I've owned have had excellent seals on that hatch so I rarely smell(ed) exhaust. Even with the rust holes in my current muffler. My old '94 if I drove several hours and stopped, set up in an RV park, sometimes, if conditions were adverse, I would smell exhaust but it would go away before bedtime.

[imnprsd]

You probably are also experiencing a hotter than usual bedroom.

So you need to visually investigate ASAP!

My guess is that you have a cracked exhaust manifold.

The turbo attaches to this and the exhaust manifold bolts are often rusty. So before you try to replace the manifold you need to soak the exhaust bolts with PB Blaster or Liquid Wrench for 2-3 days... to avoid breaking them.

You might just need a new gasket. That's what happened to me.

To know for sure you need to open your engine trap door -- and the let some drive the coach, while you look for leaks with your hand. Note: You need to drive the coach to create back pressures so you can find the leak...

Or not... if you see black smoke surrounding an area.

Note: Rusty looking and spotted exhaust manifolds are normal. Dirty black smoke is not!

Most buy new manifolds, which I hear are heavier duty castings, but I think it's also possible to take your old manifold to a machine shop to have them sand-flat the flange so it mates really good with a new gasket. The goal is to remove any "Warp."

I have heard that some people have welded the exhaust manifold crack without removing the manifold from the engine, but most say the welds don't hold. IDK. I have never done it myself.

Keep us posted on your fix!

PS
This is a good time to inspect your turbo and if you are close to an overhaul shop the turbo kits are only $60-$100. Plus you can balance the impeller if you want... and change the bushing out for a roller bearing. Most certainly you don't want to put back a near-dead-turbo if you just went to the trouble of removing it.

PSS
Want to go a step further. Look into adding a FASS or AirDog 12V electric fuel pump. And buy a performance module from Ag Diesel. ...And adjust your valves if you have over 90,000 miles... replace the belt and inspect your alternator, which normally only last ~80K miles.

And if you have never changes your Transmission Fluid, shame-shame. Do a search to learn how. It's easy after you watch the YouTube Video and buy the right stuff... TES295, Dexron Fluid and Allison dual filters.

[Jim_HiTek]

Oh, yeah, manifold leak. Forgot about that. Yes indeed, that can definately cause the exhaust smell in the BR. I had that.

I had a '94 Bounder with Freightliner chassis and a Cumins 5.9 and it had a broken exhaust manifold bolt that imnprsd mentioned. I published an ad free article about the engine because one of my readers pointed out the soot at the fan end of the engine. Here's how it looked:



So I bought a newer modern gasket, and a set of manifold bolts, and headed for Mexico. Had the broken manifold bolt removed, new gasket, bolts, cover gaskets changed, and other things checked by diesel mechanics in Mazatlan. Cost under $200.

Seven years later I sold the rig, without any new manifold leaks and all bolts in fine condition.