Exhaust Carbon Deposits

[bcripps]

Just replacing my Exhaust Riser on my Volvo diesel and was surprised at the carbon build up. I assume the carbon deposits are throughout my system. N. Calder suggests in his book that the system be cleaned but gives no instructions on the process.

Any ideas without having to rebuild the engine? And by the way, she runs like a charm.

Many thanks,
Bry

[DeepFrz]

You should be able to look into the exhaust manifold with the riser off to see how bad it is Koched (pun intended) up. If it is really bad then pull the manifold and use a wire brush to clean out the deposits. I don't have a lot of faith in the chemical cleaners you put in through the intake.

To keep it clean make sure you are not over propped and run the engine so that it reaches full operating temp. every time you are out. Running at WOT for a few minutes on your way in to the marina is a good practice or every few hrs. if on a long motor trip.

[sailorchic34]

I took my exhaust riser off and ran a small chain (small 1/4" links like used for a dog lease sometimes) through the u bend and piping and used that with a sawing motion to clean out the carbon. I since then 5-6 years ago, replaced the discharge elbow.

[bcripps]

Sounds like a dirty job.
But thanks all...
I was also concerned about the hoses and water-lift silencer. I'm not at a marina but at anchor down island. Jobs like this take on a whole new prospective down here.

Thanks again...
Bry

[Captsteve53]

The riser tends to take the brunt of the build up, the rest of the system due to the temp and sea water flow takes way longer to accumulate

[atoll]

you can use an "oven cleaner" spray for carbon deposits takes a few hours ,but dissolves any hard carbon deposits once you have removed loose surface deposits,available at most supermarkets,use rubber gloves when applying as quite caustic.

[bcripps]

More great info... Thank you, all...

Good news about the piping and might give that oven cleaner a try. Nothing to lose, right?

Bry