Rudders and Plumbing

[jphud]

Hello Out There,

Getting my 1980 Hunter 30 ready for season.

-Should there be a seacock on the exhaust thru hull, just in case?

-My rudder has some surface cracks on one side.

-The skeg has what appears to be a previous repair but it looks suspicious. Would the skeg have to be removed to replace the shaft if the engine remained in place?

Pictures below.

Thanks

 

[John T1594]

My previous boat was a 1980 H30:

There was no factory seacock on my exhaust thru hull. The thru hull was a fiberglass tube that would have to be ground out to fit a metal thru hull and seacock. The exhaust tube made a high loop inside the aft lazarette.

If the rudder is not leaking when you haul the boat, it is probably OK. You could sand down the surface cracks to see just how deep the run and then make a patch with epoxy.

The skeg is bolted on and should be stable if you try to move it back and forth. There is a seam where it is joined to the hull but I don't think that water could get into the boat if the seam leaked or if the skeg came loose.

I had a mechanic remove my shaft and he did not have to take off the skeg but I'm not sure how he did it. There may be enough room if you take the shaft off the engine coupling and slide it out through the shaft log and prop strut. If that does not work, I have heard that it may be easier to loosen and raise the engine enough to slide the shaft out forward under the engine.

 

[rardiH36]

-Should there be a seacock on the exhaust thru hull, just in case?

This probably not desirable. If the engine happens to be started without the seacock opened, the exhaust can't escape. Pressure might blow apart something? Also, the cooling water that is injected at the elbow for ejection out of the boat with the exhaust instead will fill up the exhaust tube and muffler, until it reaches the exhaust elbow level. Then it will flood the exhaust manifold and then into the cylinders. I've read that water in the cylinders is usually a sudden and fatal event for an engine.

The high loop in the exhaust tube will keep the outside seawater from migrating backwards. Also on my boat (a 1980 H36), the exhaust port from the hull is above the water line. So even if the fiberglass tube that is molded into the hull becomes damaged, or the exhaust hose doesn't seal on the tube for some reason, it shouldn't be catastrophic. When the boat is docked water can't get in through this means. However, when I'm motoring under full power, the stern wave does "raise" the water level enough to cover the exhaust port. As does healing while sailing.

 

[ggrizzard]

Your skeg looks like mine always has. (I bought mine new). I'd grind lightly on the crack to eliminate it, as water intrusion might cause permanent damage. There are numereous threads on what to use to fill in repair area to be found on this web site.

 

[jphud]

Thanks for the info.
I will check my exhaust discharge, It is below the waterline mark, will not know for sure until it launches next week.

 

[sandpiper10471]

The rudder surface is likely cracked because of water intrusion which then froze during the winter. Once the core of these is wet, it is almost impossible to dry them out without a total rebuild. In the meantime, you can grind out the cracks using a 14:1 bevel then rebuild the surface using epoxy and fiberglass cloth or polyester and chopped mat with alternating layers of cloth. Fair with resin thickened with cabosil. Next fall, drill some deep holes from the bottom edge up and inspect for saturation. If you are lucky, a nearby boater may have a moisture meter and you can do your own rudder survey.

 

[Mathurin]

Gelcoat was very thick on hunter rudders, so the stress crack might just be gelcoat grazing. I would sand one of the crack down to see if the fiberglass underneat is cracked. You may start by drilling a hole under the rudder at the lowest point to see if thee's some trapped water.

For the seacock on the exhaust, unless you don't have a waterlock and you a scared of water flooding the cylinders after you've shuft down the engine while under sail and healing a lot, I wouldn't bother... anyway if it's like on a H37C the exhaust outlet was molded in the hull.

 

[Ed Schenck]

Here is how your rudder was built by Foss Foam: http://newrudders.com/?page_id=12 . If you drill holes about three or four inches from the bottom you can drain the rudder. The foam holds the water because of the hard glass/gelcoat surrounding it. I used to drill mine every year at winter layup and then fill in the spring. The main entry point for water is where the glass goes around the shaft at the top.

 

[jphud]

Thanks much for the info.

Will be lightly grinding/ sanding area to check it out. Boat was not in water last year. I will drill to check and drain water in fall.
After closer inspection the muffler needs to be replaced and will most likely switch to water lift.
I read that my water heater needs to be installed below the manifold for the heat exchanger set up to function properly. It is an 11 gal Seward that currently only is hooked up to the electric but it is above the engine. Do I have to move it?

 

[Ed Schenck]

I had not heard that about the heat exchanger to tank relationship. I would have guessed that my tank was higher. But then I saw the pictures in the other post this morning, "Expensive mistakes . . .". So I found a couple of my own pictures. My hoses actually go lower than the tank and back up. But only slightly. How did someone find room for an 11 gal. tank on an H30? Would you be able to move it to a lower place?

 

[jphud]

I have not found a way to move it out of the compartment area where it currently resides, may need a magician.

 

[kloudie1]

Heater tank should be OK a little higher than manifold but you should have a high point bleed to enable you to get all the air out so there would not be an air lock.. Once the air is out, should not be a real problem as long as the coolant cap and gaskets (both) are in great shape. The difference should not be more than a foot or so.. and the exchanger connections on the tank are ones where the elevation is measured..
If the tank and tank exchanger are higher than the manifold the problem is that anytime the cap is opened, the water in the heat exchanger will try to get out and admit air into the system. As long as the cap stays closed and the catch tank doesn't go empty and the catch tank hose is not leaky.. it should work fine.