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Mercruiser raw water plumbing?

hi,

so so I got my engine pulled, BBC, and found an interesting through-hull under the engine. It’s tee’d into the raw water intake hose. I am new to this so I wasn’t sure if this was “normal”? Isn’t the raw water source the big hose from the outdrive? I’d like to remove this through-hull under the engine. It’s almost impossible to get to or service so that isn’t comforting, these are things that sink boats.

here are a few pictures.
https://cimg3.ibsrv.net/gimg/www.off...2afb4cb5c.jpeg
https://cimg4.ibsrv.net/gimg/www.off...cf122c61d.jpeg

hello , i guess a few question,,year,,make ,,drive..??
does seem strange to have extra pickup....
do u have a bravo drive ???

...........

Sorry, it’s a mid 90s 454 mag gen V with a bravo 2. I have been told that it has never run in this boat and I don’t know what the original engine was. There shouldn’t be anything special about this boat and I prefer things to be simple and bulletproof so I’d like to remove the through-hull fitting.

I was thinking that the cooling setups are pretty universal and wouldn’t have too much variation. This one was closed and I’m not sure you could get a hand in there to open it and it looks pretty corroded. All bad in my book.

Jason

I'm not sure it would be that way without seeing everything like it was. I was thinking that maybe they had a raw water wash down and couldn't get water past the outdrives water pump or something but the pump from the drive being T'ed to a pick up in the bottom of the boat there is no reason the outdrive pump wont just pump the water out of the bottom of the boat and not to the cooling system. I'm thinking you had a different motor drive in the boat at one time and during the change someone thought it would be better to have 2 water pick ups. Now if it was a Volvo Penta that would be fine being they don't have water pumps in the drives. A merc drive has a pump in the drive.

What kind of boat is this ? Is it some sort of fishing boat ? Does it have live bait wells or a raw water wash down system ? Your B2 system should pull the cooling water through the transom and then to the front mounted water pump . What your pic shows looks like there's a pump somewhere that pulls the water through that filtering system and then it should go somewhere else . I just can't figure out the T in it and where that would go.

just some heads up you might need a new engine coupler and you need NEW ground studs 4 sure 100 %.., also new Y pipe exhaust boots. No offense just saying.. How are the water shutters in the Y pipe - good condition - missing or bad / burned up ???

Big question here Why is there flotation foam squeezed out from the top corner of the inner transom plate assembly ??

BUP , to me it looks more like a leaf or seed pod off of some plant , not flotation foam. Mind you , I do wear correctors..!

interesting,,,yea maybe some sort of wash down system???
as to the pick up under motor, unless your good with glass work, i think i would just close off the pickup.
cant ask prior orwner???

Thanks all. I guess I could ask the PO. Originally it did have a different engine, just not sure what. The PO put this one in. Yeah, it’s tee’d into the strainer and the strainer was then connected to the engine water pump so it should have the option of two sources.

I can can do the glass work am am leaning that way. It is a fishing boat and could very well had a diesel originally. That might make sense.

I know it’s a fishing boat but I’m asking here because you all don’t take shortcuts in methods or materials and neither do I. My family’s health and safety relies on the equipment so I over build everything.

I don’t see any reason to keep the thru-hull. I could make it work but there is no standard precedent for needing it. I have yet another if I need to plumb bait tanks.

I’ll start a new conversation for the engine. It needs works hence the reason I pulled it. You guys all pointed out it’s easier to work in the garage than upside down in an engine bay. Also it may come to a new one Vs repairs so that should be interesting.

That is indeed an acorn. There are lots of holes in the transom to fix, the engine deck need to be rebuilt and I want a flush hatch that doesn’t dig in as badly when leaning over to work on stuff.

Thanks
jason

Mercruiser raw water plumbing? Yes How