PVC Pipe for a Wet Exhaust ?

[SabreKai]

I noticed that the Vetus mufflers I got from Irish Queen were all attached to PVC pipe instead of wire reinforced hose. Anyone have any comments on this practice? I am thinking that doing the exhaust from the muffler to the exhaust port on the transom in PVC would solve a lot of routing problems.

[barnakiel]

Sure it was PVC?

If the exhaust is cold then who knows maybe it will work fine. How does PVC interact with sulphur / acids / etc.?

b.

[MikeTurner]

I know PVC pipe isn't recommended for plumbing from the head to the holding tank because the rigid pipe won't "give" with the movement of the boat. So I wonder if a similar issue would exist for long runs of PVC pipe in the exhaust? Over time the PVC fittings might work loose allowing exhaust water and gases into the boat?

[s/v Jedi]

These plastic Vetus exhaust parts quickly burn up when seacock is closed or impeller broken (any time no water flows). Better go with Centek parts. They make waterlifts, separators etc. but also pipe, 45- and 90-degree elbows etc. These are fiberglass parts so can easily be modified, laminated into hull etc.

cheers,
Nick.

[Target9000]

When we install our engine and redid the exhaust plumbing our vendor told us the same thing Nick said... We had an old Vetus muffler and replaced it with a Centek. If for some reason you don't have water being injected into the exhaust line the heat of the exhaust will melt through most materials. Why take a chance?

[GordMay]

ABYC "P-1", doesn’t list PVC in it’s extensive list of approved materials for engine exhaust systems, and I wouldn’t recommend it for such use.
I would second the recommendation for Centek Fibreglass Reinforced Plastic, meeting the UL 94V-0 Flammability test, in a Wet Exhaust system.

“INSTALLATION OF EXHAUST SYSTEMS FOR PROPULSION AND AUXILIARY ENGINES”
P-1 ➥ http://www.abycinc.org/committees/P-01.pdf

[David M]

No way, not for exhaust. It is too brittle and has too low of a melting point. Yes, it might work for a while. But is might good enough?

One can only go cheap to a point where you then start endangering lives and sacrifice reliability.

[s/v Jedi]

wow... it's not often that everybody agrees with me... there must be something wrong (especially since Vetus is Dutch like me :-)

ciao!
Nick.

[David M]

Nothing wrong...just a random coincidence.

[capn_billl]

PVC has too low of a melting point for Exhaust, even on a good day as the temp increases the strength decreases, allowing it to deform and possibly leak. I like PVC and use it a lot, but I would never use it for that. Also it burns easily giving off poisonous gasses. It can even outgas chloramines when heated.

[foggysail]

Originally Posted by MikeTurner

I know PVC pipe isn't recommended for plumbing from the head to the holding tank because the rigid pipe won't "give" with the movement of the boat.

REALLY???? Sure is much better than stink hose!

Foggy