thruhull question

[moombadaze]

think its possible to run two reversible pumps off of one thruhull. I don't really have a good spot to add a thruhull to feed a 4th reversible pump, I then thought about just adding a Y fitting between a existing pump and thurhull and then be able run a xtra pump and not have to drill thru the bottom of the boat. I'm pretty sure the one inch hose should flow enough water for both pumps. Drilling a hole in the bottom is no big deal to me, its just real tight for room along the vdrive. Pumps are for two separate bags and could both be running at the same time or run separately as the bags are different size's, I wont ever be trying to fill one or empty the other at the same time as there on the same side and will be used for surfing.

[jstenger]

I would probably "Y" into the starboard bag. Since this forth pump is for the bag under your portside seat, chances are that you would not be filling the starboard bag at the same time.

I know that you already have a forth pump on hand, but I believe you didn't know where to mount the switch. You could skip the pump all together and add a wye valve to your starboard bag. No need to add the pump or wiring. Fill the seat bag when surfing, or fill the starboard bag when wakeboarding.

Don't know if you already did it, but you could vent the seat bag into the portside bag. Once the seat bag is full, it would help fill the 1100 that you have. This would cut down on fill time.

[MLA]

think its possible to run two reversible pumps off of one thruhull. I don't really have a good spot to add a thruhull to feed a 4th reversible pump, I then thought about just adding a Y fitting between a existing pump and thurhull and then be able run a xtra pump and not have to drill thru the bottom of the boat. I'm pretty sure the one inch hose should flow enough water for both pumps. Drilling a hole in the bottom is no big deal to me, its just real tight for room along the vdrive. Pumps are for two separate bags and could both be running at the same time or run separately as the bags are different size's, I wont ever be trying to fill one or empty the other at the same time as there on the same side and will be used for surfing.

Yes, we do it quite often. Rather then a Y fitting somewhere in the plumbing between the thru-hull and an existing pump, I would recommend a T fitting right on top of the thru-hull to feed each pump.

Since you are considering adding on to an existing thru-hull, you need to consider the size of the thru-hull if the two pumps will be in the fill mode at the same time. When we do this for a dedicated surf setup, we pair up pumps that will almost never be drawing off the thru-hull at the same time.

Filling one and emptying the other is not a problem.

[moombadaze]

I would probably "Y" into the starboard bag. Since this forth pump is for the bag under your portside seat, chances are that you would not be filling the starboard bag at the same time.

I know that you already have a forth pump on hand, but I believe you didn't know where to mount the switch. You could skip the pump all together and add a wye valve to your starboard bag. No need to add the pump or wiring. Fill the seat bag when surfing, or fill the starboard bag when wakeboarding.

Don't know if you already did it, but you could vent the seat bag into the portside bag. Once the seat bag is full, it would help fill the 1100 that you have. This would cut down on fill time.

Joe, thanks for the idea of Ying into the starboard bag, was thinking of using the port bag thruhul-your way makes more sense. I have allready run the vent line to the vent, as i didnt want to vent it into the other bag so the timer stays correct for filling and emptying. Im trying to stay at 10-11 minutes fill for everything, the front tank and ibs take that long as does the 1100 so haveing the underseat spill/fill into the 1100 wont really help me for total time.

[moombadaze]

Yes, we do it quite often. Rather then a Y fitting somewhere in the plumbing between the thru-hull and an existing pump, I would recommend a T fitting right on top of the thru-hull to feed each pump.

Since you are considering adding on to an existing thru-hull, you need to consider the size of the thru-hull if the two pumps will be in the fill mode at the same time. When we do this for a dedicated surf setup, we pair up pumps that will almost never be drawing off the thru-hull at the same time.

Filling one and emptying the other is not a problem.

I'll have to see if there is room for a T ontop of the thru hull, pretty tight for space down there, may have to go with a Y . With Joe's idea of using the starboard thurhull i should be ok on two pumps not filling at the same time, just emptying, I do add some ballast on the starboard side now but filling the under seat bag full and then adding 20-30% to the 750 on the starboard should still be well under my 11 minute till all is full goal.

[bergermaister]

Daze - if I had to do it all over again I would do dedicated thru hulls to feed each pump independently of each other. Granted I'm not running reversibles and the T-1200s may have a higher flow rate, but I bet even with a lower flow pump on 1" lines one will be greedier than the other. Physics, mechanics and all hydro-engineer BS aside, that will be the real world effect.

Then there's the not worrying about which pump is running at what time and potentially conflicting with empty/drain operations...

My .02

[moombadaze]

Daze - if I had to do it all over again I would do dedicated thru hulls to feed each pump independently of each other. Granted I'm not running reversibles and the T-1200s may have a higher flow rate, but I bet even with a lower flow pump on 1" lines one will be greedier than the other. Physics, mechanics and all hydro-engineer BS aside, that will be the real world effect.

Then there's the not worrying about which pump is running at what time and potentially conflicting with empty/drain operations...

My .02


I agee with everything you wrote, ive thought of most of them. Biggest issue is being able to drill the hole and have it be perfectly in place, looks like if im off a 1/8-1/4 inch and ill be screwed for being able to work the ball valve handle. If I can get away without absolutley needing it then it may be the best solution. I may run the 2 pumps off one thru hull and see how it works, if it doesnt work out i can allways add the xtra thruhull and replace the pumps very easily. i have a xtra thruhull and ball valve too if needed.

[bergermaister]

Have you looked at doing a 90 off the thru hull and then to the ball valve sitting horizontal?

I'm actually planning to separate my pumps sharing a single thru hull and go dedicated to each before next season. May go that route due to space issues.

[moombadaze]

Have you looked at doing a 90 off the thru hull and then to the ball valve sitting horizontal?

.

Yep, sat there for what i swear was a hour with thruhull,ballvalve in hand, trying to figure a good place. Not even sure a 90 before the ball valve would help much, the water intake and giant ball valve for the motor is my biggest space issue

[bergermaister]

Pretty sure mine doesn't have a ball valve on the raw water intake. Just take it off and go direct - problem solved! ;)


(Warranty? We don't care about no stinkin warranty....)

[moombadaze]

Pretty sure mine doesn't have a ball valve on the raw water intake. Just take it off and go direct - problem solved! ;)


(Warranty? We don't care about no stinkin warranty....)

Dont think my 08 had one either, this one does and boy does it takes up space

[chadjitsu1]

I actually did a bunch of testing with johnson pumps and using a Y and a T fitting. You absolutely get better flow and quicker fill times in your bags if you just use one pump per bag.

Ideally if you surf a lot or are concerned with weighting the boat from one side to the other then I would add a 5th pump that is connected between the two v drive bags in the back that just pumps water back and forth. If your surfing on one side and want to switch you could easily just flip a switch to move water from one side to the other wile emptying the side your moving water from and filling the side your moving water to. It sounds complicated but between the two back bags you would actually have 3 pumps. I am actually thinking about doing this mod now just because even with the upgraded 4 pump johnson system switching surfers is a total pain in the butt. That mod would absolutely cut the time in half.

Also if your wakeboarding and one side is washed out you could easily just move water from one side to the other to clean it up. Lots of cool stuff you could do.

[moombadaze]

Im pretty sure I have only had one person ever surf goofy behind my boat, so fast switch out times are no big deal for me. I did get out this weekend and test everything--my under seat bag filled in about 4 minutes, when it was full I started filling the starboard rear bag for a little offset weight-both using the same thru hull, all while the 1100 was filling. for me this worked perfectly as Ive cut down fill time and increased one bag in size.

I did not drill any holes or make any permanent mods to the boat, some future owner may like that