Good advice, and true whether you use a flange or a tube through.If you go with flange on a cored hull, make sure it has been de-cored and glassed preferably for 1-2" radius not just filled. Over time any underwater joint will leak I find LOL
Always use the shortest length stub at transom as well as any bend points! Also best to have the joints accessible at all times or at least viewable, worst case, have a planned point to cut an access AND use best materials IE silicon hose at coupling.I think anything you got should be the lowest profile possible, ie flush with hull as much as practical, then it's not gonna see much abuse in the first place.
To me always seems a liability to have a sub waterline appendage there, especially a fiberglass based one that's essentially glued in place if you think about it.
Glassing something in its real tempting to have the tube partly outside the hull as it gives you someplace that's easier to tab to. But it doesn't need to be done that way either - it can end up quite flush.
It's not a bad thing to have some flexibility in the exhaust system. In my mind - you really shouldn't have a fiberglass tube running the length of half the hull, glassed in like it's a structural member.. And then if it's not actually permanently part of the hull, say its only passively mechanically attached, it seems odd to make the outlet end permanent. If I was gonna glass the outlet, I'd still have a coupling there - let the transom flex without pushing on the entire exhaust system.
I went with a pacer pump for emergency pump out because I think in the chaos of an emergency, an engine pump out system takes time to get sorted out with seacocks even though it should not, oil rags normally this bilge area, Not really a high flow rate given other options, plus you got to worry about flow for cooling engine.
Roger that, Captain!I ve had a few boats now with the tube glassed from the transom to the exhaust elbow. Never seen an issue or a crack. This is what I prefer as it's simple, streamlined and no clamps. I've seen lots of leaky exhaust clamps over the years. They can easily sink a boat
To be clear I'm not saying you shouldn't have bilge pumps. I'm just saying that the engine makes a good cheap emergency pump. How big is the inlet hose on the pacer pump, 2" with a seperate motor? the little Cummins B is 2". Rev it up and it moves a lot of water, let alone what a Cat C18 could move. lots of pump for almost no extra plumbing and loose rags will clog any pump. If theres water nothing is overheating. But I would'nt take the Pacer out if it was already in. Batteries underwater are batteries submerged whether it's high capacity Rule pumps or ECM's. And if we are talking about a Pacer gas pump, that's 1 whole different engine to maintain and hope starts when the time comes.I went with a pacer pump for emergency pump out because I think in the chaos of an emergency, an engine pump out system takes time to get sorted out with seacocks even though it should not, oil rags normally this bilge area, Not really a high flow rate given other options, plus you got to worry about flow for cooling engine.
How big is the inlet hose on the pacer pump? the little Cummins B is 2". Rev it up and it moves a lot of water, let alone what a Cat C18 could move. lots of pump for almost no extra plumbing and loose rags will clog any pump. If theres water nothing is overheating.
They are either hydraulic SAE take off drive, like a Cummins raw water pump requiring the main engine, or seperate drive requiring a "pony" engine/motor. So in the time it's needed you can move valves or start a seperate engine.I think you probably got good flow.
Issue in my mind is more, you got a problem, now you are stressed and down in the bilge messing w/ plumbing to fix it that's probably also underwater.
That same plumbing designed to let you pump out could also sink your boat or destroy your engine waterpump, engine even, if it is misused or fails somehow.
A separate electric pump is a pump and outlet, a switch on your bulkhead - at least as simple as a couple valves to turn your engine supply to the bilge. You get stressed, you flip a switch to turn it on. I don't know what he means by pacer though, could be electric, hydraulic, or a complete combustion engine trash pump the way I understand the term.
And why is the main engine overheating? It doesn't care if it's raw water flow is coming fom inside or outside the boat. This wasn't meant to be the only way to survive offshore. I was just saying that with a single screw boat you can put in a hell of an emergency pump for about $150. See it in huge Carolina sportfishes all the time.