Cummins 330HP ISC problem

[Gorlininc]

I have a 2001 diplomat.
While driving up a mountain yesterday near Yosemite my engine got louder like the exhaust fell off.
Oil pressure and water temps are fine. Turbo boost is fine. There are no oil leaks.
Exhaust manifold and muffler were changed last year and look ok. All the exhaust gaskets on the head to exhaust manifold are there. The exhaust break works fine but is very loud when engaged. I know nothing about Diesel engines. We have a Machanic coming Monday. But want to see if anyone has an idea of what could of happened.
Thanks
Rick

[Skip426]

A cracked exhaust manifold is a very good possibility.
Turbo mount gaskets, bad flange clamp.
Takes a fairly large leak to make the boost drop.

[Gorlininc]

Thanks off your reply. Doesn't sound like anything major. The engine sounds like it has no muffler. You can here it in the drivers sets while accelerating. Very quiet while coasting. I suppose it could be the exhaust manifold again. Only have about 10k on the old one.

[Skip426]

Increased noise when exhaust brake is in use, sounds like problem is between the cylinder head and the exhaust brake. Turbo may have come loose from the manifold and blown the flange gasket.
I'd be tempted to put a wrench on all the bolts before the mobile mechanic arrives, see if you can avoid the call out charge.

[dennis45]

To me it sounds like you have an exhaust leak between the Exhaust Brake Butterfly Valve and the Turbo. There normally is a gasket between this flange held together by a clamp. Either the clamp is broke or the gasket has let go.
When you activate the exhaust brake there is a lot of pressure at this joint and if it is not sealed you will hear an exhaust noise.

[Gorlininc]

I hear loud noise also when accelerating. I'm pretty sure it's an exhaust leak. I'll take a look in the morning at the turbo gasket and the coupling around the exhaust break.
Maybe something just might have come loose.
Thanks for your replies

Rick

[Gorlininc]

I had a Machanic come today to check out my engine. The exhaust pipe after the exhaust break had a flexible hose welded to it going to the muffler. The weld broke releasing all the loud engine noise. He's making me a new one and will install it tomorrow. Luckily an easy fix. Not sure of the cost but 2 trips out here an hour each way is $500 alone, plus labor and parts. A cheap fix in my book. Could have been a lot worse.
So we continue our 8 month trip out west.
Thanks for all your replies
Rick