Rigging a transom mount water pickup?

[Mr. Demeanor]

A little more progress. Modified bracket is mounted. If the wind allows, tomorrow I will make a couple passes with the pickup tube out of the bracket then put it in and see how it effects speed/handling mounted with the leading edge flush. May move it up and down and bit to get an idea of how it effects the boat. It wont even be plumbed to the motor for this test. I have to drive an hour to Parker Hose to get an adapter for the 1/2" compression fitting they used to go to my 3/4" hose.
Thanksgiving company comes in Monday so I probably wont get to to run it all plumbed to the motor until the first week in December.

[RiceKiller]

I hope they didnt charge you much for that it could be made rather easy

[Gorilla0178]

I'm really interested on how it works too......

[Mr. Demeanor]

Its going to be awhile before I play with this more. One of my goals with this was to eliminate the nosecone but I think I need the lift I am getting from it.
I went out yesterday with my fastest prop and tried to get an idea of how the pickup effects speed but it was too windy to get a solid pass with and without the pickup tube in.
I did run into an unforseen problem. I beached the boat and reached under the transom to slide the pickup tube into place and found that the back of the sponsons was actually sitting in the sand! The boats sits so bow high with nobody in the front seat that the pcikup tube was stuck in the sand. When I walked the boat to deeper water to tighten the pinch bolt, I found that the pcikup tube was clogged with sand/mud. It wasnt plumbed to the motor but this could be a deal killer for the project. That beach area has a real gradual slope but so do a lot of the places I go.

[fast fun 2]

I have done this on two boats. I would suggest using the lower unit water pickup along with transom mount. Do not use cheap clear hose as suggested. On the transom pickup use a check valve to so that at idle the water pump (lower unit pickup) can do its job and pump water. Run the line ( I used SS braided hose) to the midsection right below the powerhead their is a plug you can tap into. I have also run the line to the top of the block on another boat. This setup will self prime as you put the boat in the water just like you have now. I would run the line into the boat and to the engine at the pivot point with all the cables and fuel lines.

I agree +1

[afr]

that stuff aint for goofin just real time runnin you know what im saying

[Mr. Demeanor]

Dissapoimted in Bobs product. I had to grind the back of the "stainless" 90 degree fitting they welded to the square pickup tube to get it to sit flush. When I did that I noticed it was painted silver. I figured they just did that to make it look nicer after welding. Well, it rusted terribly where I took the paint off. Grabbed a small magnet and picked the whole fitting up. I'm not sure if you can weld iron to stainless but it sure seems that is what they did. I have seen a magnet stick to cheap stainless but not like this. $50 worth of crap and I cant return it becasue I modified it.

[XstreamVking]

What if you made one from 3/16" stainless flat stock and bent it to match the trans angle you need? Make it about 1.5" wide and take the needed size brass fitting (1/2"?)and tap and thread it flush with the bottom of the plate. With a longer threaded fitting you could make it angled to scoop more water... Just throwing out ideas here. .. Bob's has some great stuff, but their not perfect, I got some solid mounts and they didn't fit properly. Called them up and was told to get them turned down to fit...Quality ain't there on all their parts..

[Gorilla0178]

I found this place had some small scoop pickups that get plumbed through the bottom of the boat. I was wondering about plumbing one at the very back of the pad. They look pretty hydrodynamic.

[Mr. Demeanor]

I had to use an adjustable style and cant plum it in through the transom as the entire back of my boat is foamed in. It would make a very clean install but digging out all the foam to route the water would be a nightmare. I have what I have and will do some testing and then if it all works out, will make something up a little more custom. For now, I am just going to route some hose and see hwo it effects speed. I would hate to do a bunch more work to only find I cant go any faster by going higher or get on plane any higher.......

[Gorilla0178]

How do the motors handle the extra water pressure? Do you have to gate them down with a valve. i can only imagine the increase in press. going that fast. Anybody ever rig a through hull pickup? In my boat it would be as easy as drilling a hole and sticking it in.

[Mr. Demeanor]

Bobs stated by plumbing it to the water pump, the pump actually acts to regulate water pressure. They said it would not make any more pressure than the pump would create on its own.

[Gorilla0178]

Really, thats cool. Where exactly do you drill to plumb into the pump? I know on the lower just under the cav plate, but is there a measurement or is it just eve ball. Its a 200 OMC? I really like the little scoop that rex marine has, what size hose is normally used, they have 2 sizes, 5/8 and 3/4?

[Mr. Demeanor]

It wlil be plumbed in to the existing fitting for my Bobs nosecone so I dont have to do any additinal plumbing. I am sure someone here can guide you on how to set up your OMC. Problem with the scoops is they create more drag. With the adjustable models, you can keep raising the pickup reducing drag until water pressure starts to drop off.

[Gorilla0178]

More drag yes, but could it be any more than a nose cone? Unless you can jack the motor sky high.