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zimm17
05-30-2007, 08:27 AM
I looked at every water pickup I could find on the internet. I even ordered a stainless marine brand pickup which was gigantic. About 7" tall with a 1 1/4" pipe on it. I only need a 3/4" pickup for the whipple intercooler.

I couldn't find a small transom mount, but now I'm thinking about a through hull model. I ordered this 3/4" one from Dana:

http://www.danamarineproducts.com/ProductDetails.cfm?group_id=44&catid=218&productid=3536&CFID=310334&CFTOKEN=66694975

Now the question is how to install it? Obviously I drill a hole in the bottom of the boat, stick the fitting in, and cut it flush with the bottom. So...where do I put it? Can it be higher up on the V-hull by the trim tab? How far up from the transom? Is the hull thick enough for screws not to stick down? I plan to 5200 glue it in place too. Also I will have a ball valve on it for safety.

Waiting for advice.

mrfixxall
05-30-2007, 08:40 AM
zimm,the water pick up you selected i believe is a through hull fitting for flushing your engine.. look at this link,theirs a few 3/4'' fittings that go on the bottom of your boat..Do you plan on using a electric water pump to circulate the water through your inner cooler? you also want to mount the water pickup as far back to the transm to the lowest point on the boat,kinda by your drain plug...i prefer the scoop style myself..and yes use 5200 but plan on never removing it tho.
http://eddiemarine.com/store/cart.php?m=product_list&c=114

Rodger
05-30-2007, 08:51 AM
I installed my pickup for the intercooler through the hull. I placed it about half way between the keel and the first strake and about 15 inches forward from the transom. I just used an old inboard (60's vintage clam shell type) brass pickup. It is not flush with the bottom: it has a scoop design. It moves plenty of water. After the water has circulated through the intercooler it is still relatively cool compared to the oil temp. I then route it through my second oil cooler before discharging the water. Once the boat is planed off, water is flowing through it. (My primary oil cooler is fed by the water pump through a thermostat.)

mrfixxall
05-30-2007, 09:06 AM
one more thing try to filter or use some kind of a seastrainer before the inner cooler so all the lake water crap doesnt plug up then inner cooler...

Cuda
05-30-2007, 09:29 AM
Be sure to seal the inside of any hole you drill with epoxy.

BigGrizzly
05-30-2007, 09:38 AM
DO NOT drill through tge hull. use the Stainless Marine, than you can lose the one in the lower unit all together. My son's wipple uses only the lower unit for everything. Now be very careful you do want the water pressure over 35PSI. or it will generate problems in the engine! This is fact, I have done alot of supercharged engines. that why race boats have a pressure relieve bypass on them. The higer the boost the more important it becomes.

rustnrot
05-30-2007, 09:56 AM
Check out this new engine cooling water intake. Big footprint, obviously needed to get required flow but flush with hull!
http://www.gemlux.com/catalog.aspx?page=itemDetails&item=87001

zimm17
05-30-2007, 11:12 AM
So nobody thinks the flush 3/4" hole in the bottom of the boat will get enough water into the intercooler? I could tap off the low water pickup from the imco shorty, but I'm worried about not enough water going through the heat exchanger. I have closed cooling, so no water pressure goes through the block- just the 16psi radiator cap holding pressure for that. Right now the raw water goes through the heat exchanger, p/s cooler, oil cooler, then the exhaust. I was going to run the pickup to the intercooler then out an overboard dump.

The Stainess marine pickup was really, really big. And I already returned it.

I could go with one of the transom mount 1" models, but I don't see why the flush pickup won't work. No drag on the bottom, nothing to snag stuff, and wouldn't there be enough water pressure to feed the cooler?

I'm going to run the dump out the starboard side right below the bilge pump outlet so I can see the water flow while underway.

MOP
05-30-2007, 12:02 PM
A flush fitting may supply water properly in fact it may have suction, I would try Ting off the pump relying on the drive pickup. I would install a pressure gauge and as long as the pressure stayed at a reasonable level would call it a day. Another point a through hull fitting placed to close to centerline will disturb flow to the prop, you want the cleanest flow possible.

Phil

smokediver
05-30-2007, 12:21 PM
IMCO has a nice pickup ... looks like a rams horn and fits around the drain plug in the outside of the transom ... looks like all you have to do is drill a hole above the drain ...

gcarter
05-30-2007, 02:52 PM
So nobody thinks the flush 3/4" hole in the bottom of the boat will get enough water into the intercooler? I could tap off the low water pickup from the imco shorty, but I'm worried about not enough water going through the heat exchanger. I have closed cooling, so no water pressure goes through the block- just the 16psi radiator cap holding pressure for that. Right now the raw water goes through the heat exchanger, p/s cooler, oil cooler, then the exhaust. I was going to run the pickup to the intercooler then out an overboard dump.
The Stainess marine pickup was really, really big. And I already returned it.
I could go with one of the transom mount 1" models, but I don't see why the flush pickup won't work. No drag on the bottom, nothing to snag stuff, and wouldn't there be enough water pressure to feed the cooler?
I'm going to run the dump out the starboard side right below the bilge pump outlet so I can see the water flow while underway.
Get one of the Stainless Marine 1" pickups and, like Mop said, blank off the drive pickup. The 1" pick up will give you more than enough water for EVERYTHING going on inside in the engine compartment. It only stick 1/2" below the hull. Also include a sea strainer.
Griz was right, this is the right way to do it.
http://www.donzi.net/forums/attachment.php?attachmentid=24272&d=1159816499

zimm17
05-30-2007, 03:27 PM
All right, I won't use my flush water pickup.

I'm going to T-into the output from the sea water pump and use a water pressure gauge to verify I have enough psi. If not, I'll go with the stainless marine pickup. I heard the IMCO shorty lower picks up a lot of water. Worth a try before I go through all that work to install the transom mount. The T fitting is the cheapest and easiest.

Should I still put the 3/4" overboard dump on the starboard side below the bilge dump- or go out the back?

The Hedgehog
05-30-2007, 06:24 PM
All right, I won't use my flush water pickup.
I'm going to T-into the output from the sea water pump and use a water pressure gauge to verify I have enough psi. If not, I'll go with the stainless marine pickup. I heard the IMCO shorty lower picks up a lot of water. Worth a try before I go through all that work to install the transom mount. The T fitting is the cheapest and easiest.
Should I still put the 3/4" overboard dump on the starboard side below the bilge dump- or go out the back?

Go out the side above the waterline. It will be easier to monitor that way. I ran mine out the back but will probably move it to the side.

BigGrizzly
05-30-2007, 07:23 PM
The imco does flow a lot of water that should be fine. If you decide to yse the transom pichup use a 1 1/4 one the 1 inch is for a 350. Thw bbc are already plumed for 1 1/4 hose

Rodger
05-30-2007, 10:30 PM
DO NOT drill through tge hull. use the Stainless Marine, than you can lose the one in the lower unit all together. My son's wipple uses only the lower unit for everything. Now be very careful you do want the water pressure over 35PSI. or it will generate problems in the engine! This is fact, I have done alot of supercharged engines. that why race boats have a pressure relieve bypass on them. The higer the boost the more important it becomes.

Griz,
How will the high water pressure hurt the engine. Isn't the intercooler completely separate from the engine cooling system? If the intercooler is in the engine cooling system, then I understand. My intercooler is completely separate.

p729lws
05-31-2007, 03:58 AM
If you go transom mounted check out the Imco adjustable pickup. It's similar to gcarter's but has an adjustable tip. Mine's set up flush with the hull and picks up fine. I have a spare one in the garage w/ a 1-1/4" barb connection that was left over from my last project. Let me know if you want it.

http://www.donzi.net/forums/showthread.php?p=370677#post370677

gcarter
05-31-2007, 07:47 AM
If you go transom mounted check out the Imco adjustable pickup. It's similar to gcarter's but has an adjustable tip. Mine's set up flush with the hull and picks up fine. I have a spare one in the garage w/ a 1-1/4" barb connection that was left over from my last project. Let me know if you want it.
http://www.donzi.net/forums/showthread.php?p=370677#post370677
That's a nice looking pickup.
To me, one of the advantages of the Stainless Marine pickup is, with the pipe thread, a metal shut off valve can be screwed onto the pipe. I know of at least two of our members who have nearly sunk their boats because a hose failed and there was no way to turn off the water entering the boat.

p729lws
05-31-2007, 12:43 PM
That's a nice looking pickup.
To me, one of the advantages of the Stainless Marine pickup is, with the pipe thread, a metal shut off valve can be screwed onto the pipe. I know of at least two of our members who have nearly sunk their boats because a hose failed and there was no way to turn off the water entering the boat.

Is the SM piece standard pipe thread? You can get the IMCO unit w/ an AN thread or the barb. It's a PITA to get from AN to a standard threaded valve w/o some hose in between. Standard pipe thread would have been much better. We were going to go w/ the barb option then changed direction due to the reasons Gcarter listed which is how I have the left over barb type pickup. If you go the barbed route I'd definately have hose clamps professionally done.

Dan

gcarter
05-31-2007, 01:59 PM
Is the SM piece standard pipe thread? You can get the IMCO unit w/ an AN thread or the barb. It's a PITA to get from AN to a standard threaded valve w/o some hose in between. Standard pipe thread would have been much better. We were going to go w/ the barb option then changed direction due to the reasons Gcarter listed which is how I have the left over barb type pickup. If you go the barbed route I'd definately have hose clamps professionally done.
Dan
The SM piece is standard tapered pipe thread. It is mounted by six screws through the flange. I'll be installing another soon and I'll take lots of pics.

p729lws
05-31-2007, 04:24 PM
The SM piece is standard tapered pipe thread. It is mounted by six screws through the flange. I'll be installing another soon and I'll take lots of pics.


Cool. The adjustable section of the IMCO isn't all that sophisticated so maybe it's possible to adapt it to the SM model.

Dan

zimm17
05-31-2007, 04:38 PM
Well I got my 3/4" dump fitting mounted on the starboard side. I ran the 3/4 wire reinforced hose from it to the intake only to find that the fittings on the intercooler are 5/8" :banghead:

Now I need to call Hardin marine and get the 5/8 vice the 3/4 pressure valve to go with my inline "T".