Thru hull water pick up installation help

[tgr23]

For my 1995 208.

I installed a live well this past season and used a simple hose over the stern for water intake. That worked only ok, not great at speed though. I'd like to install a thru hull this Spring before the boat goes in the water. I'm a little unsure where to put it though. The live well lives up against the motor well. The hoses to the pump run through the aft bilge. Pump is mounted on the stern wall next to the oil tank.

My options as I understand it:
-a simple thru hull fitting off the stern? Seems like that will be out of the water on plane.
-PVC or brass?
-High speed strainer mounted under the hull at the stern? How hard is it to mount this sucker in the aft bilge?

Thank you in advance for any advice or tips.

Travis

 

[DennisG01]

You're right, if the pickup was mounted through the transom it would only function at trolling speeds. While I can't help with the exact placement of the thru-hull on your particular boat (at least not w/o seeing pics), the general process is the same with all boats. You'll install: high-speed pick-up -- seacock with flange mount -- inline strainer. Bronze is my preferred choice, next would be Marelon. I would not, personally, use plastic below the waterline.

Some thoughts to pass along...

-- Be sure to double clamp (and rotate 180*) all hoses.
-- Take measurements on the hull bottom where strakes are, then drill a pilot hole through the hull from the inside in a good location (accessible, but not a "trip hazard").
-- Glass a wooden block on the inside of the hull where seacock will mount and drill large hole.
EDIT: Forgot to mention... check to see if there is already a wooden block glassed onto the hull.
-- Chamfer both edges of the hole for better sealant adhesion.
-- Coat the interior of the hole (hull and wood) with epoxy.
-- Countersink screw holes for seacock (sealant adhesion).
-- Do not use 3M 5200. Personally, I like BoatLife LifeCalk.

 

[BobP]

Add your boat to the signature and engine too if you prefer so it's always there.

Is the 1995 208 the center console? Do you want water pressure while underway ?

Forget plastic, keep it in your wallet.

Your model offered SW pickup for washdown, I bet, check full year catalog on Grady website for 1995 year catalog, if they still have cats there. You have to access area to create new pickup hardware, operate valve handle to open/close, and new SW pump and wiring etc "locate and install".

It's very close to replicating same SW washdown (on any of the Gradys of similar length. Part for part. As a matter of fact, cut to length cheap 5/8 garden hose from SW spigot to well, and done with. The shorter the better. If you had the SW wash down as equipped.

They do use a lot of juice over time, so be prepared to wipe out a battery or two soon enough and have nothing left to start ship's motor with. Not uncommon, always learning experience.

 

[Pez Vela]

If mounted correctly, your existing "hose over" the transom will perform well while the boat is at rest or traveling at high speed. The intake hose may be clamped to a short length of rigid pipe (6" of PVC for example) which is cut at a 45º angle at its trailing end. In my application (I did this 40 years ago in an 18' boat) the rigid pipe was then snapped into a break-away clip which was attached to the transom just above the waterline. The pipe was snapped into the clip so that the tip of the pick-up protruded perhaps a 1/2" below the hull bottom, with the "open" edge of the 45º pipe facing forward. There used to be a ready made kit, but I don't know if they are still available. Your thru-hull option is to mount a intake strainer on the hull bottom, as you noted. Working on boats is never easy, and boat plumbing is no exception.

 

[DennisG01]

If you really wanted to "Macgyver" it, install a remeote pitot sender and zip tie the hose/short pvc tube assembly to the pitot. The pitot senders have a built-in "kick-up" feature.

Heck, if you wanted to, just use small zip ties and attach the assembly to a trim tab. You could probably even skip the PVC tube and just slightly relieve the front section of the hose.

 

[tgr23]

I want to extend an apology for not responding to these very helpful posts. I do not know what happened when these responses came in but I totally missed them. Now that my brain is thawing, like my boat, I'm undertaking this project....among others. I think I'm going to go with the Macgyver method but utilizing some sort of "kick up" pilot sender unit.

Thanks again!
Travis

 

[fishbust]

I recommend the MacGyver method as well. Every hole we drill in a boat is another liability. There are enough holes in these boats. Too many if you ask me.

 

[jbrinch88]

Why ruin the look of your boat with a hose hanging over it? Thats a halfass way of doing an install if you ask me. If done properly installing a thru hull is no big deal. Also glassing in a backing plate is not necessary, I've installed tons of under water thru hulls using the supplied backing nut only with no problems.

Simply find a spot that will be easily accessible to shut off the sea cock if a hose splits. Make sure it'll have water to it when the boat is on plain. I usually install them a few inches away from the rear bilge pump. We use boatlife's life seal product and I've never had an issue with it. I never use 5200 in case you have to service it, removing it will be a pain in the ass.

FYI you can find the sea cock shut off valves at a local plumbing store. The last one I bought I paid 7$ for vs the Groco ones which are more.

 

[tgr23]

I would actually consider the thru hall more except finding an exact spot to install it has not been revealed. Installing one through the bilge area looks near to impossible. I see no way to actually get down there to do the work. I dread the day i need to replace the bilge pump for that very reason. Anyone know of an accessible place on a 208?

Thanks

 

[jbrinch88]

Theres no inspection plate? I had a 1988 20' Grady and just like the others, there was an inspection plate mounted to a hatch that was also removable if you took out the screws/cut the caulking/and pried it up.

 

[tgr23]

Would those be in the motor well? I'll take a look next time out to the marina.
Thanks

 

[DennisG01]

Boats are typically not "easy" to work on, but there's usually a way. Although sometimes that means cutting an access hole and reinstalling a plate. I'm not familiar enough with your model to be able help with that part, but maybe if you had some pictures? Too bad you weren't in the Allentown, PA area - it'd be easy to help then!

BoatLife makes great caulk/sealant - excellent stuff. And I whole heartedly agree with the statement about NOT using 5200 - good stuff, but there are very few applications for it. This is not one of them.

Not to start an argument, but I disagree with the notion about not glassing in a wood block. I understand what you're saying about "never had a problem", but that doesn't mean it never will be a problem. The idea is to be proactive and prevent future (possible) problems. There's a reason doing this is considered "best practice". If this was only a flush-head transducer with no lip or hole (for things to get stuck in), then it's much less of an issue.

 

[jbrinch88]

I agree with you that glassing in a backing piece of some kind is definitely the right way to do it. On my personal boats that I've owned I've done it that way for sure. But if not being able to do that kind of work yourself and that's going to make or break your decision for not installing a thru hull, I think you'll be fine without it. I just think having a hose going over the side, or running some pvc setup would ruin the look of the boat.

 

[tgr23]

Couple questions Dennis.
-What do you mean by "rotate the hoses 180 deg"?
-How thick and wide a block of wood do you fiberglass in the hull

Thanks
Travis

 

[jbrinch88]

he's referring to the hose clamps I would assume. Put the first hose clamp on then the next one below it make sure they are opposing eachother 180*. This way you can bring them in alittle closer to eachother and being able to fit 2 instead of 1.

Backing blocks that I've put in were anywhere from 2-4" wider/longer in each direction of your hole that you drilled. Can be longer or shorter not sure if there is a "correct" size. I usually use 1/2" or 3/4" plywood, also using a nice piece like oak or something would be better. Not the cheap stuff.

 

[tgr23]

Another question.
-What determines the pipe size of the pick up and the seacock?
Looking on-line there seems to be a wide range of options.
Thanks

 

[tgr23]

Would you just screw the seacock to the backing plate or drill out and install bolts to come from underneath and through the backing plate? I guess the bolts might hinder tightening down a high speed pick up since it can only face one direction when installed.

 

[DennisG01]

he's referring to the hose clamps I would assume. Put the first hose clamp on then the next one below it make sure they are opposing eachother 180*. This way you can bring them in alittle closer to eachother and being able to fit 2 instead of 1.

Backing blocks that I've put in were anywhere from 2-4" wider/longer in each direction of your hole that you drilled. Can be longer or shorter not sure if there is a "correct" size. I usually use 1/2" or 3/4" plywood, also using a nice piece like oak or something would be better. Not the cheap stuff.

Yes, clamps - thank you. Another reason for rotating the clamps is that the typical worm-screw clamp does not actually seal 360*. Where the screw is, is sort of a flat spot. By rotating, you get a better "total" seal. Personally, I usually use marine ply - but I tend to always have some of that laying around. At $70-$110 a sheet (usually can only buy it locally in 4'x8' sheets), it doesn't make much sense to buy a sheet for JUST this purpose. Regular ply will be fine - especially since it's going to be encapsulated and overdrilled. Never use anything pressure treated as it can outgas and cause delamination of the resin (unless it's been thoroughly dried for quite some time).

 

[DennisG01]

The pipe size you choose is dependent on what kind of draw you anticipate. This is determined by the pump you are using, how many pumps will use this through-hull and anticipation for the future. Most pumps use 1/2" fittings so going larger doesn't really help. But it's usually best to upsize (for good measure and future use) - 1" is typical. You can downsize to the appropriate barb after the seacock (or right at the seacock with the correct pipe to barb adapter).

Correct - the base/flange of the through hull mount or seacock will get screwed down. This is another good reason to use a block since you are screwing into the 3/4" piece of wood, not your hull bottom.

 

[tgr23]

Pulled the motorwell hatches and it looks like the through hull is a doable operation. I picked up the bronze strainer and seacock, 1". We'll start glassing in the wood next weekend. Thanks for the advice and encouragement.
Travis