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-   -   Trans cooler dumps (https://www.offshoreonly.com/forums/general-q/359249-trans-cooler-dumps.html)

ttrm007 02-24-2019 08:26 PM

Trans cooler dumps
 
I'm trying to figure out the best way to dump my trans cooler water overboard. They are 3/8" hose. I see 3 options:
1. Send two 3/8" through hull dumps out the sides of the boat. Would be able to use much shorter through hull fittings.
2. Send two 3/8" through hull dumps out the transom of the boat. I would need to find a spot that doesn't dump all over all of my rigging just to keep things cleaner?
3. Send one 3/4" through hull with a tee out the transom. I'm not sure if these would fight each other and if one motor had a litlte more pressure than the other, it could it prevent the other from draining.

I'm leaning toward number 1 but am worried you guys are going to say it will look like a jetski or something :)

ICDEDPPL 02-25-2019 09:33 AM

https://cimg1.ibsrv.net/gimg/www.off...7397a655c6.jpg



I dump everything overboard off the side . Like you said shorter fittings and easier to access.
Once in a while you might get a question on why are your bilge pumps running all the time? lol

F-2 Speedy 02-25-2019 09:45 AM

ICD, are dumping any intake water ? I'm going to dump two -6 per intake to relieve the hot water issue in the rear of the intake

slpcamaross97 02-25-2019 10:36 AM

I recall that the side of the outlet was important on a trs transmission cooler. My boat has smaller fittings for the discharge. I can take a picture tonight for you. But its defiantly less than 3/8 fitting. My boat is all original with merc2 transmissions.

ttrm007 02-25-2019 05:44 PM


Originally Posted by slpcamaross97 (Post 4674289)
I recall that the side of the outlet was important on a trs transmission cooler. My boat has smaller fittings for the discharge. I can take a picture tonight for you. But its defiantly less than 3/8 fitting. My boat is all original with merc2 transmissions.

Thanks for input all.

Slpcamaross97,
I understood the in and out to not matter on merctrans so would be interested in learning more. Makes sense to me that you are just running cool water through a set of internals to cool the oil so direction probably shouldn't matter? The lines on the in and out on the trans are 3/8" so I'm assuming 3/8" would be the dump.

Tom

cig28 02-25-2019 06:39 PM

https://cimg9.ibsrv.net/gimg/www.off...8da12bcf9e.png
Here the way I ran them , my boat has merctrans, I ran the dump above the drives now they pump water on the drives as a drive shower.

Rookie 02-25-2019 06:45 PM


Originally Posted by F-2 Speedy (Post 4674279)
ICD, are dumping any intake water ? I'm going to dump two -6 per intake to relieve the hot water issue in the rear of the intake

Like this? I just route it back into the exhaust. Was going to go over the side but decided to go back into the header.

https://cimg3.ibsrv.net/gimg/www.off...2c997f8064.jpg

ICDEDPPL 02-25-2019 07:42 PM

^^^ you`d have to have higher pressure in the block then the headers.. otherwise there will be no water flow. Isn`t the pressure the same in both?


https://cimg5.ibsrv.net/gimg/www.off...43cbcda3d9.jpg

I have two -4AN dumps above the drives.

Rookie 02-25-2019 08:28 PM

That's what I thought at first, it would flow a little, just enough to get rid of the hot spots. I actually put restrictors in the black hose (1/4" drill holes) because the back of the intake and heads ran noticeably colder. I guess path of least resistance, it's pretty much open atmosphere in the tails with a vacuum pulling the water out the pipe.

https://cimg1.ibsrv.net/gimg/www.off...d156b9ae83.jpg

ttrm007 02-26-2019 06:58 PM


Originally Posted by ICDEDPPL (Post 4674396)
^^^ you`d have to have higher pressure in the block then the headers.. otherwise there will be no water flow. Isn`t the pressure the same in both?


https://cimg5.ibsrv.net/gimg/www.off...43cbcda3d9.jpg

I have two -4AN dumps above the drives.

Interesting option but I can't figure out what kind of fitting will be long enough to go through the transom. Do you know what -4an fitting you used? Some kind of bulkhead mounted fitting?


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