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ZekesterbluH3
06-30-2009, 06:54 PM
I'm re-installing the external water pick-up...when I noticed how low it sits with it bolted into the original position. If you look at the pics, it appears 3/4" too low, and with the reinforcing web where it is, and the angle it is on, it would have to act as a mini trim tab...in the one pic you'll notice that the water would hit the pick-up flat, this must be a huge drag...

Should I move it up so the web is behind the transom? Will it get enough flow if just the openings are exposed to the water?

Conquistador_del_mar
06-30-2009, 07:23 PM
Yep, it needs to be raised until the fins are at the bottom level. Bill

farmer tx
06-30-2009, 07:27 PM
I have the same P/U and it is below the hull amout 3/16 of an inch.

HIGH LIFE
06-30-2009, 07:30 PM
Installed one on a banana years ago, kept it down app. 1/8", never a problem, owned boat for 13 years. Mine didn't have fins inside. HIGH LIFE

gcarter
06-30-2009, 07:41 PM
Wow, that looks like a lot of work to move it up that small amount.
Since it seems you'll have to do some transom glass repair work anyway, have you given any thought to changing to a physically smaller pickup like a Stainless Marine? I've used three of them so far and have bveen pleased with the small size and ease of installation.
http://www.donzi.net/forums/showthread.php?t=49388&page=2

ZekesterbluH3
06-30-2009, 08:13 PM
I'm just going to epoxy in a round plug, then re-cut the main hole. The two bolt holes i'll epoxy dowels into. All the holes are covered by the pickup, so as long as I apply sealant there, it should be ok. Access inside is hell with the stern drive mount there etc...I'll just seal the face of the plug on the inside with sealant or epoxy...

so at most I should just hang it 3/16" below the hull?

I wonder how many mph that thing hanging there scrubbed off?

farmer tx
06-30-2009, 08:25 PM
Can you imagine the water pressure that thing is putting on the cooling system? I'm surprised your not having head gasket issues.

ZekesterbluH3
06-30-2009, 08:34 PM
I just want to clarify this...since the finned part is angled compared to the bottom, should I mount it so the deepest point is 3/16"? So the rearmost part would be 3/16 down, the front would almost be flush with the bottom...or are you guys saying the front edge is 3/16" down, and the rear is lower in the water...

MOP
06-30-2009, 08:46 PM
Pressure relief valve time! Not only should it be raised but probably will need a relief valve, it if not raised will cause quite a bit of drag and even more system pressure. I would have nothing more then the strainer section protruding below the bottom plate above! Install a pressure gauge try to keep system pressure down to about 20 psi, most head gaskets will start to weep around 30psi.

Phil

farmer tx
06-30-2009, 09:21 PM
I loaded the pic large so you could see it better.

ZekesterbluH3
06-30-2009, 09:27 PM
Thanks for all the input...I can't believe it came from the factory like this..maybe it had a different pick-up before? I believe it was a factory TRS boat but this has me scratching my head...

The Hedgehog
06-30-2009, 09:33 PM
Can you imagine the water pressure that thing is putting on the cooling system? I'm surprised your not having head gasket issues.

No joke,

My Latham pickup sticks down a 1/4 inch or so and it does not angle forward. I use a water pressure gauge. It normally runs around 8-10 PSI

ZekesterbluH3
06-30-2009, 09:50 PM
perfect, a pic=1000 words..I blew up your pic..and see exactly what I have to do....

BUIZILLA
07-01-2009, 09:52 AM
mine is mounted slightly lower than farmer's... but not by more than 1/8" or so