Location of Thru-Hull on Shallow Bilge

[Darkzillicon]

Is there anywhere to get guidance on the location of thru hulls on the bottom of a boat? I know I need them where it is deepest at the transom as to not have the pumps run dry but I don't want to have an issue where the thru hulls are in the way and people step on them. Just wondering if there is a best practice or resource regarding locating them.

19' Boat with a Design waterline of maybe 4" or so... wooden glass fiber/epoxy boat. maybe 3.5" of bilge height in the nearly flat transom.

 

[gonzo]

Are you saying that the through-hull fittings will protrude from the deck?

 

[Darkzillicon]

Yes... they will so assuming I need to make a machinery area in the middle area of the rear of the boat. However I know sometimes when moving boats they use forklifts, and I don't know if there is an expected place for the thru hull...

 

[gonzo]

What is the intake for?

 

[fallguy]

Don't you have a splashwell?

 

[Darkzillicon]

Don't you have a splashwell?

not doing a splashwell. outboard bracket off the transom to improve the issues that DOGCALVARY was seeing with his sled.

Also current transom is 24” so cutting down for a splashwell would make it more like 18” for mounting outboard or Jackplate so I think the Armstrong bracket is the way to go. Motor is 350 pounds.

 

[Darkzillicon]

What is the intake for?

A/C unit 9K BTU ... 3/4" Thru Hull Scoop Strainer Groco. Probaby can Mount Filtration out of the way. just access to the thru hull and lever for shutting it off should be convenient.

 

[Darkzillicon]

I made a quick drawing of what I am thinking... I also did some spaceplanning last night and it seems like i need to build a machinery space low and amidships for the batteries 3x and the a/c unit (no generator) and the thru hull and strainer and associated plumbing.

I guess my main question is is there a best practice or a place these are expected to be on the hull? I know quite often i see powerboats lifted with forklifts at a marina and it seems like the thru-hulls are more towards the center of the boat so that the forklift can lift on the outside near the chines. I could be wrong but that's my understanding.

Yellow highlighted area is where thru hull would be amidships. Twin keels.

 

[gonzo]

It looks like you are planning on keeping the boat at rack storage, so they will pick it up with a forklift. I would install the pickup at the transom like a transducer. It would also be easier to unclog.

 

[Darkzillicon]

It looks like you are planning on keeping the boat at rack storage, so they will pick it up with a forklift. I would install the pickup at the transom like a transducer. It would also be easier to unclog.

That was my first idea but due to the low height of the deck and the equipment in the middle I was concerned that you wouldn’t be able to walk in the back to handle lines. Or I’d have to raise the deck to protect the thru hull.

What I do like about the idea is that the transom should be really low in the water with the weight so the pickup won't suck air with the nearly flat transom.

 

[fallguy]

Like I told DC. Splashwell also offers place for start batt and home for rigging.