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jordanmc
01-01-2016, 04:02 PM
So I did it again, Went out for a great ride today and lunch in Florida around Boca Grande. I literally touched a shallow spot for 10 seconds and bingo sand sucked in and my temp started rising so I shut it down and got a tow in. I have the 496 HO with the Bravo drive with the high speed pickup which is great for speed but is the first thing to hit the sand. I don't believe I did any damage as I shut it down before it even hit 180 degrees but its unrealistic to think I won't pull sand again. Should I switch over to a completely closed system and eliminate the need to suck in any water?
Any other things I could try first (other than not hitting the sand :)

Morgan's Cloud
01-01-2016, 05:10 PM
You still need to suck in raw water even if you install FWC and in the event you suck in sand it would probably interfere in some way with the heat exchanger tubes.

It sounds like a good strainer might be in your future .

jordanmc
01-01-2016, 09:53 PM
You are bang on. I know it wont cure the problem but I think I should get a sea strainer. I have been searching through tons of old posts and there is tons of great debate on which brand to go with and if you should go with a transom mount water pickup. I am still learning so this concept is knew to me. I have a 2001 496HO with the water pickup right on the front of torpedo. This might be a stupid question but can you install a sea strainer without changing to a transom mount pickup or should I do the transom mount pickup first? Which strainers are people using these days the posts I was looking at are pretty old.

Ghost
01-01-2016, 11:24 PM
You are bang on. I know it wont cure the problem but I think I should get a sea strainer. I have been searching through tons of old posts and there is tons of great debate on which brand to go with and if you should go with a transom mount water pickup. I am still learning so this concept is knew to me. I have a 2001 496HO with the water pickup right on the front of torpedo. This might be a stupid question but can you install a sea strainer without changing to a transom mount pickup or should I do the transom mount pickup first? Which strainers are people using these days the posts I was looking at are pretty old.

Love my Hardin on my 496--uses the drive pickup. Also have the Hardin SS pump.

f_inscreenname
01-01-2016, 11:55 PM
That's another reason I like having the water pick up in the bottom of the boat.

Ed Donnelly
01-02-2016, 03:59 AM
I would go for the transom pick up first. You my find you don't need the strainer then..Ed

jordanmc
01-02-2016, 08:04 AM
Thanks guys,
I have to say I don't completely understand how the transom water pickup works. If my boat has the inlets on the front of the torpedo which is a foot or so in the water then how is the boat going to suck enough water from the transom mount when I am trimmed out and flying at 80?

MDonziM
01-02-2016, 08:43 AM
I don't know what your hull is but a transom mounted water intake is just what it sounds like . There are different products but they scoop up water off the bottom running surface of the hull at the transom. The water is sucked in by your existing (or upgraded) water pump, bypassing the outdrive altogether. You have a low water pickup on your drive now which is designed for boats with a high X-dimention, meaning the drive is mounted relatively high in the water making the traditional pickup location on the side above the bullet ineffective. I would personally install a good strainer first, then go to a transom pick up if needed. I had a Livorsi strainer on my 22 which worked great. The main thing to consider is where to best mount it for access and plumbing the water intake hose to and from as it is pretty stiff. They make the strainers with a variety of strait or 90degree inlets. Sorry, don't know why the strainer pics went sideways. The last pic shows the pickups on my magnum but they are tough to see black on black, they are also an old style but you get the idea.

- M

gcarter
01-02-2016, 10:46 AM
Here're some pictures from several years ago, and they show a 1" Stainless Marine transom pickup and the interior plumbing to a hugely oversized NOS Perko strainer that I got for less than $100.00.
The idea is to cap off the through gimbal plate fitting inside the boat and to remove the hose between the upper gear case and the gimbal housing.
Here's a link to the inner block off plate:
http://www.mercruiserparts.com/Show_Pictures3.asp?dnbr=17721&ivar=images/COMMON/4294.png&inbr=952&bnbr=190&bdesc=GIMBAL+HOUSING+COVER

And if you look here, you'll see to remove parts #14, 15, 23, 24, 25, and 26. The plate listed above replaces
#23, and 24.
http://www.mercruiserparts.com/Show_Pictures3.asp?dnbr=17721&ivar=images/COMMON/38659.png&inbr=952&bnbr=40&bdesc=GIMBAL+HOUSING

Finally, here's a link to the Stainless Marine transom pickup.....they used to list a 1" pipe size, I'd ask about it.
http://www.stainlessmarine.com/shop/1-14-npt-male-x-1-58-od-stainless-transom-mount-water-pick-up-ea/

http://www.donzi.net/forums/attachment.php?attachmentid=82644&d=1277069183

http://www.donzi.net/forums/attachment.php?attachmentid=82645&d=1437353874

gcarter
01-02-2016, 10:52 AM
Also, i use a remote mount closed cooling system like this:

https://www.perfprotech.com/high-performance-fwc-system-full-flow-700hp-capacity-pn-mrm-5321-hp427rh-k1/product/246892

Ghost
01-02-2016, 12:17 PM
So I did it again, Went out for a great ride today and lunch in Florida around Boca Grande. I literally touched a shallow spot for 10 seconds and bingo sand sucked in and my temp started rising so I shut it down and got a tow in. I have the 496 HO with the Bravo drive with the high speed pickup which is great for speed but is the first thing to hit the sand. I don't believe I did any damage as I shut it down before it even hit 180 degrees but its unrealistic to think I won't pull sand again. Should I switch over to a completely closed system and eliminate the need to suck in any water?
Any other things I could try first (other than not hitting the sand :)

Maybe I'm wrong, but I don't think there's any system that doesn't need to suck seawater and run it through an exchanger.

To Mark's point earlier, perhaps it's time to disconnect the intake line from the drive and put an intake fitting on the hull itself? Something along the lines of:
83500

f_inscreenname
01-02-2016, 01:20 PM
Here's another "old school" transom pick up from 1967 so they have been around a while.

http://www.supernova19.com/67da6330.jpg

Ghost posted the one that I have in the 19 and Biese (the Biese has two pick ups with one also in the whip strut). The only issue is (I don't know crap about he Bravos) if the Merc has a water pump in the drive. My boats have a raw water pump on the front of the motor. A circulation pump alone wont cut it.

gcarter
01-02-2016, 02:19 PM
Here's another "old school" transom pick up from 1967 so they have been around a while.

http://www.supernova19.com/67da6330.jpg

Ghost posted the one that I have in the 19 and Biese (the Biese has two pick ups with one also in the whip strut). The only issue is (I don't know crap about he Bravos) if the Merc has a water pump in the drive. My boats have a raw water pump on the front of the motor. A circulation pump alone wont cut it.

Alphas have (marginal) pumps in the drive, and folks are better off getting rid of them.
Bravos don't and use engine driven pumps.
The one in the picture looks similar to the pickup supplied by Merc for TRS drives.

MDonziM
01-02-2016, 03:03 PM
Maybe I'm wrong, but I don't think there's any system that doesn't need to suck seawater and run it through an exchanger.

To Mark's point earlier, perhaps it's time to disconnect the intake line from the drive and put an intake fitting on the hull itself? Something along the lines of:
83500

That is not a performance style pickup, more for a cruiser. Bob's, Stainless Marine, Hardin etc. make performance pickups. Closed cooling systems are just heat exchangers so they run raw water around a core of water/anti-freeze. They require an automotive style circulation pump in addition to the raw water pump.

MDonziM
01-02-2016, 03:09 PM
Alphas have (marginal) pumps in the drive, and folks are better off getting rid of them.
Bravos don't and use engine driven pumps.
The one in the picture looks similar to the pickup supplied by Merc for TRS drives.

George - that pickup is too close to the centerline to clear an outdrive, I would assume that is a v-drive boat with some sort of rudder. That location would also disturb the water in front of the propeller (no good) of an outdrive if it were possible.

- M

gcarter
01-02-2016, 03:28 PM
George - that pickup is too close to the centerline to clear an outdrive, I would assume that is a v-drive boat with some sort of rudder. That location would also disturb the water in front of the propeller (no good) of an outdrive if it were possible.

- M

Marshall, you're absolutely correct. That's Brownie's old twin/in-line V-drive race boat.
I was merely commenting on the shape of it.

smokediver
01-02-2016, 03:41 PM
So I did it again, Went out for a great ride today and lunch in Florida around Boca Grande. I literally touched a shallow spot for 10 seconds and bingo sand sucked in and my temp started rising so I shut it down and got a tow in. I have the 496 HO with the Bravo drive with the high speed pickup which is great for speed but is the first thing to hit the sand. I don't believe I did any damage as I shut it down before it even hit 180 degrees but its unrealistic to think I won't pull sand again. Should I switch over to a completely closed system and eliminate the need to suck in any water?
Any other things I could try first (other than not hitting the sand :)

You already have a closed cooling system. Get a sea strainer and enjoy !

gcarter
01-02-2016, 03:44 PM
I have a couple of issues w/a "through the bottom" pickup;
First, it requires a hole in the bottom of the hull, a possible place for failure
w/a hard impact on the bottom.
Second, I rented a house in the Keys once that came w/a 20' CC boat.
It had a transom mounted depth sounder puck mounted a little over
2' from center line. That puck really upset the handling of the boat.
Any time you went much over 35 MPH, the boat would lay over to one
side like you were dragging a tab. It wasn't my boat, so I did nothing about it.
But I recognized how sensitive to trim, etc. devices on the bottom of even moderately
higher performance boats are.

wwahl
01-02-2016, 06:03 PM
My first 16' Donzi, 1965 year, had a through the bottom pick up. Every time I'd run over a kelp bed it would suck the stuff in and overheat the motor.

jordanmc
01-02-2016, 06:45 PM
My Bravo one seems to only have one water pickup which is one small hole on the front of the torpedo. Is that normal? Most seem to have dual water pickups from what I have seen

gcarter
01-03-2016, 10:43 AM
I understand they come in different configurations.

Greg K
01-03-2016, 11:09 AM
Bravos come in three different versions, Dual, Std, and Lower only. Like was said before you already have a closed cooling and only need a strainer in the long hose from the transom to the raw water pump.


My Bravo one seems to only have one water pickup which is one small hole on the front of the torpedo. Is that normal? Most seem to have dual water pickups from what I have seen

jordanmc
01-03-2016, 11:16 AM
Got it, I will do that. Thx again

jordanmc
01-03-2016, 11:44 AM
I know its not brass but thoughts on this one?
http://www.hardin-marine.com/p-15757-1-npt-dual-screen-swirl-away-high-performance-sea-strainer-with-pressure-relief-valve.aspx

or this one

http://www.go2marine.com/product/112963F/perko-bronze-sea-water-strainer-with-flushing-fitting.html

Greg K
01-03-2016, 12:01 PM
The $329 and or $399 one is just fine. Will need a pair of 1" pipe plugs and a pair of 1" npt to hose fittings.

gcarter
01-03-2016, 12:31 PM
IMHO this one, w/o the flush feature, is better for limited space. The flush feature is great in larger engine rooms.
http://www.go2marine.com/product/86121F/perko-bronze-raw-water-intake-strainer-493-series.html
You just have to make sure there's overhead clearance for basket removal. This is probably the fastest
opening strainer on the market. You can cut down the basket height by cutting the hoop/handle in two
and rolling the edges over to make two handles. Another advantage of this strainer is, it never loses it's
water, or prime. It stays full all the time. Some of the strainers on the market don't, I.E., they can drain
down every time you pull the boat out of the water.
I'd recommend the 1-1/4 size.

f_inscreenname
01-03-2016, 01:24 PM
I thought we were talking about sand????? Unless it has a sand filter its useless in this situation. You are gonna need something like this,


http://www.hardin-marine.com/images/Product/large/625-4620.jpg
PS, you are not getting sand out of the filter with a basket.
Again not being a dick here but if I were you I would start thinking about solving the problem instead of fixing symptoms. I have 3 feet of water at my boat ramp on a good day and have to cross a sandbar 100 feet from the ramp. Almost guaranteed the drive will touch bottom at some point. Rebuilt my motor this past late Fall. No strainers, no filters and not a single grain of sand in the motor or exhaust.

gcarter
01-03-2016, 01:48 PM
I thought we were talking about sand????? Unless it has a sand filter its useless in this situation. You are gonna need something like this,


http://www.hardin-marine.com/images/Product/large/625-4620.jpg
PS, you are not getting sand out of the filter with a basket.
Again not being a dick here but if I were you I would start thinking about solving the problem instead of fixing symptoms. I have 3 feet of water at my boat ramp on a good day and have to cross a sandbar 100 feet from the ramp. Almost guaranteed the drive will touch bottom at some point. Rebuilt my motor this past late Fall. No strainers, no filters and not a single grain of sand in the motor or exhaust.

Anything heavy settles in the Perkos, the water pulls off the top.
Just a question.....how fast can you get that thing apart and empty/clean it?
Well, that may not be fast enough.

jordanmc
01-03-2016, 02:04 PM
I thought we were talking about sand????? Unless it has a sand filter its useless in this situation. You are gonna need something like this,


http://www.hardin-marine.com/images/Product/large/625-4620.jpg
PS, you are not getting sand out of the filter with a basket.
Again not being a dick here but if I were you I would start thinking about solving the problem instead of fixing symptoms. I have 3 feet of water at my boat ramp on a good day and have to cross a sandbar 100 feet from the ramp. Almost guaranteed the drive will touch bottom at some point. Rebuilt my motor this past late Fall. No strainers, no filters and not a single grain of sand in the motor or exhaust.

What is your suggestion re solving the problem instead of fixing symptoms. Do you have a different water pickup in your boat?

f_inscreenname
01-03-2016, 02:19 PM
I showed 2 pick ups. You can go with the transom mount or the one ghost posted. That's what I use in the 19. It does 65mph with a 496 and has never had an cooling issue. The race boat uses a transom pick up with strainers but they are just for floating debris (basket style) and so far I have never saw anything inside of them.
If I were you I would use the one ghost posted and be done with sand before I would drop 4,5, 6 hundred bucks on something just to stop it from going in the motor.

PS, G you ever see sand float? I have. Also take that strainer and shake it up some by bouncing over waves and I bet a milkshake of sand and water will travel without a fine filter (which will clog up easy).

gcarter
01-03-2016, 04:50 PM
PS, G you ever see sand float? I have. Also take that strainer and shake it up some by bouncing over waves and I bet a milkshake of sand and water will travel without a fine filter (which will clog up easy).

Over 90% of what packs up a cooling system is mud, silt, and floating vegetation and a basket works wonderfully. Silt and mud will pack up on a filter like you pictured.
Again I ask how fast can you disassemble that filter and clean it in a busy, constrained waterway with a current flowing while you're with out power?

jordanmc, I've given you some good advice that will serve you well.

f_inscreenname
01-03-2016, 06:04 PM
jordanmc, I've given you some good advice that will serve you well.

And I agree.
Just options. :shades:

jordanmc
01-03-2016, 07:35 PM
thx guys