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Mechmaster

Ballast Install Question

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Mechmaster

I'm installing a custom ballast system in my '98 VLX.

I have a question about the thru-hull fittings.

A typical connection to the thru-hull is like this (from Juice75's install):

172342958-M.jpg

Thru-hull fittings are made with conventional threads, but any plumbing fittings are made with pipe threads.

My question is this: are there any leakage issues when connecting a 3/4" Male threaded thru-hull to a 3/4" female pipe thread fitting? If so, how would one get around this problem?

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vette-ski

I'm planning out my ballast system as well. I'm going to do mine a little different than most. It's not in the boat yet, so I can't say it's proven, but I can't see why it won't (have it mocked up in my garage).

First, I'm using the Rule 1100 pumps with 3/4" thread on the input size. For that reason, I'm fine with a 3/4" inlet thru hull. I'm using a Perko 0266 thru-hull ( http://boxells.com/Perko/pko305-13.html 2nd item down). It screws to the bottom of the boat and is threaded 3/4" pipe internally for the plug. For the ballast system, I'm threading a 2.5" long 3/4 brass nipple from Lowes/Depot with a 3/4" brass "street" elbow (one end male, other end female) on top. A brass shutoff valve will thread onto the elbow, and then my pump will thread directly into the shutoff. My main reason for doing this is I can remove the sac system from the boat completely and not have to worry about the thru-hulls in the bottom. I can just put the plugs back in. I guess you could put a brass cap over one of the externally threaded type, but I think this looks more OEM. BTW, I got those thru hulls at my Malibu dealer....$30 including the T-handle plug.

Edited by vette-ski

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Hman442

That's a good question on the thread issue. I just wanted to add a comment based on that photo that I think it sould be real important to stick with all metal fittings until after the safety ball valve. PCV is tough, but brittle. I wouldn't want PVC "floating my boat".

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NorCaliBu
...stick with all metal fittings until after the safety ball valve. PCV is tough, but brittle.

Yes.gif I was going to post that very comment. Very important IMO.

As to the question re: threads...the thru-hull will have the same thread pitch as pipe fittings of the same "size" the only difference being that pipe threads are tapered slightly. You won't have any problems mating the fittings together. Put a couple wraps of teflon tape on them and you won't leak a drop.

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Mechmaster
As to the question re: threads...the thru-hull will have the same thread pitch as pipe fittings of the same "size" the only difference being that pipe threads are tapered slightly. You won't have any problems mating the fittings together. Put a couple wraps of teflon tape on them and you won't leak a drop.

Great!

First, I'm using the Rule 1100 pumps with 3/4" thread on the input size. For that reason, I'm fine with a 3/4" inlet thru hull. I'm using a Perko 0266 thru-hull ( http://boxells.com/Perko/pko305-13.html 2nd item down). It screws to the bottom of the boat and is threaded 3/4" pipe internally for the plug. For the ballast system, I'm threading a 2.5" long 3/4 brass nipple from Lowes/Depot with a 3/4" brass "street" elbow (one end male, other end female) on top. A brass shutoff valve will thread onto the elbow, and then my pump will thread directly into the shutoff. My main reason for doing this is I can remove the sac system from the boat completely and not have to worry about the thru-hulls in the bottom. I can just put the plugs back in. I guess you could put a brass cap over one of the externally threaded type, but I think this looks more OEM. BTW, I got those thru hulls at my Malibu dealer....$30 including the T-handle plug.

That sounds like a good idea. Be sure to take some photos of your install.

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mainekneeboarder

vette-ski,

Thats how I'm plumbing my bow sack, the Rule 1100s use 1 inch pipe thou, first one in your link is the 1 inch flange. The stock tanks are done this way with 3/4 flanges you linked to, then 1.5-2 inch long pipe tubing, valve, then pipe into pump.

Edited by mainekneeboarder

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2007vride
I'm installing a custom ballast system in my '98 VLX.

I have a question about the thru-hull fittings.

A typical connection to the thru-hull is like this (from Juice75's install):

172342958-M.jpg

Thru-hull fittings are made with conventional threads, but any plumbing fittings are made with pipe threads.

My question is this: are there any leakage issues when connecting a 3/4" Male threaded thru-hull to a 3/4" female pipe thread fitting? If so, how would one get around this problem?

I just finished installing an auto-ballast system and ran into the issue you describe when pipe thread (NPT) is mixed with straight thread (ST). I don't think there will be leakage issues but I didn't feel comfortable with the amount of turns the thru-hull threaded into the elbow. I didn't think it make a strong enough joint.

The simple solution was to return the brass components sold at hardware stores (Home Depot, Lowes, Osh) and purchase bronze elbows and shut-off valves from boating stores because they are ST. You'll be paying a bit more for the ST and bronze though, $25 compared to $8 at hardware stores.

Here's a picture of my install but it's not in a Malibu. http://www.flickr.com/photos/[email protected]/2333530328/

Edited by 2007vride

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vette-ski
vette-ski,

Thats how I'm plumbing my bow sack, the Rule 1100s use 1 inch pipe thou, first one in your link is the 1 inch flange. The stock tanks are done this way with 3/4 flanges you linked to, then 1.5-2 inch long pipe tubing, valve, then pipe into pump.

I'm using these pumps (6 of them): ebay link

They are definitely 3/4" thread on the input side. They will either thread directly into my pro-x sacs, or 3/4" fittings. It lists the output as being 1.125", but a 1" flex hose will fit over it snugly. I don't exactly understand the rationale of a 3/4" in and 1" out, but it's still rated 1100 gph.

edit: I believe the pump is a 205FM

Edited by vette-ski

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mainekneeboarder

If they are the rule 205 they should be 1 Inch. Have you got the pumps yet? Dont want to see you order the wrong stuff!

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vette-ski
If they are the rule 205 they should be 1 Inch. Have you got the pumps yet? Dont want to see you order the wrong stuff!

Yeah, pumps are in hand. I found that guy from another post here on this forum (sunscapejeff I think posted it). Seems there was some discussion around the ebay guy having pumps that aren't commonly found anymore. I went that route because the 3/4" inlet threads are easier to deal with because other fittings are easier to find. The drain pump will go right into the fly high sac, although I decided I'm not going that route. I would rather have the fly high quick connects so I can pull the sacs out easily for drying. Also, I could thread my pumps directly into those thru hulls I mentioned above if it wasn't suggested by everyone to have a shutoff valve before the pump. Has anyone ever had a pump break off at the neck?

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Ronnie

There is always a first time. I have heard but not checked into it, that it is required now. Pretty cheap insurance in my thinking. I wouldn't do PVC anywhere before a brass ball valve. Even with schedule 40 fittings it's way too easy to get broken off. You won't have anyway to stop the flow into the boat except to hold a towel over it while some one else heads for the ramp.

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Brad B

Ditto - must be brass valve.

We broke a pump off at the stem and they are very thick PVC pipe. The valve made it a non-event. And I have broken PVC ball valves that are inline to fill sacks. I would not put them between the hull and fill pump - too risky

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sunscapeJeff

Those Rule 1100's have worked out great for me.

I'm trying to think if there are any thread discrepancies in my setup, and I can't think of one. I've got a brass valve screwed directly onto the thru-hull, then a 1" to 3/4" adapter into the brass valve (I chose 1" thru-hulls in case anyone ever makes a bigger, badder pump that actually fits it, unlike the Tsunami), then the pump directly into the adapter. No fitting issues there that I know of. I just used plenty of teflon tape, and I haven't seen any leaks. For the empty pumps, they're screwed directly into the ballast sacs. Everything else is barbed, I think.

The only place I ever see leaks is where the pumps screw into the ballast sacs, and I think that's because it's not a real tight fit, and I haven't used enough teflon tape, I guess. Plus, those bags get moved around alot. Plus, I've been too afraid to tighten them up too much. Don't want to ruin the fitting on the sac.

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