Ballast valve does not close - 26s

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Be Free
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Re: Ballast valve does not close - 26s

Post by Be Free »

JamesToBoot wrote: Wed Sep 03, 2025 8:49 am
Be Free wrote: Wed Sep 03, 2025 7:56 am On the X the ballast level can be checked through the vent hole. When the boat is level and the tank is full the water will be just below the top of the vent.

Some have installed mechanical or electrical sensors. Even if I had one I'd still probably continue to check the level "by finger" before hoisting the sails.
Im thinking, just from my reading of the forum and vids, that each 26 has some sort of vent hole to check by finger.

All 26 are filled w am underwater valve and are filled via the boats weight in the water... and to check the level you need to be flat/level/not on heel. In order to check it again, you must first come back to a flat/level/not on heal. In that case, the same amount of water that could be forced out by heeling could also have come back in once you stopped heeling? At least thats what I would gather.

So the question is, what gives you confidence that you haven't missed something and that nothing has broken?
-is it soley experience (it worked reliably previously, so it should continue working?
-is it confidence in the product and theory behind the product if fool-proof?
-is it a degree in fluid dynamices engineering?

The attempt here is to gain experience from your experience (as I don't have any yet w a water ballast). I have read carefully the threads, news, and articles on boats that have sunk (testiment to the product and engineering that there are so few after so many boats made and so many years of use). All appear to be a mix of several errors on the users part and all appear to be failures of the user to be sure the ballast was full.

So what do you do to have confidence
You are correct that the constant thread through all Macgregor problems is an empty or partially filled ballast tank.

Keep in mind that I'm only personally familiar with ballast the X variants so you may need to adjust for your boat. In both the early and later model X the fill valve is in the transom below the water line. Early models have the vent valve under the companionway ladder; later models have it under the v-berth. I believe (but have no personal experience) that the M is similar if not identical.

As OverEasy mentioned the ballast tank is designed to be used full or empty, never anything in between. Never sail with a partially filled ballast. The hybrids (M and X) can empty the ballast under power (never under sail) if desired but that is the only time they would be moving with a partial ballast and only long enough to empty the tank.

The ballast tank is only filled at rest. It most commonly done at the dock and except for the motorsailers there is seldom any reason to empty it before pulling the boat out of the water. Some (not all) of us will drop our ballast in order to go faster under power on occasion but we always refill it before raising our sails again. I can't think of any reason why any of the "pure" sailboat variants would do so as a matter of course.

Just like checking the oil in your car before driving, it is a good idea to check the fill level before leaving the dock or weighing anchor. Once the tank is full there is no reason why the water level should change unless the fill valve or air vent is not secured just as there is no reason why your car's oil should be low unless you have a leak somewhere. The main difference is that low engine oil is not nearly as dangerous as a partially filled ballast tank. Get in the habit of checking it before you move the boat. It is a very important habit to develop.

If you were to sail every day for a month and remembered to check the water level every day I would expect you to find it full every time. You don't check it because it is likely to be down; you check it because it is so dangerous if it is not full.

Now, to answer your questions:

My confidence that nothing is broken comes from regular inspections and safety checks. There are a lot of thing I check but the on-topic check is to make sure that the water is at the correct level and that both valves are closed before I leave the dock or weigh anchor if I've been out overnight.

Because I've checked the tank level regularly and because I've never found it to be low I have every reason to expect it to continue to function as designed absent evidence to the contrary.

Because I know there is no such thing as a fool-proof product I continue to check knowing that some day it will show signs of failure and I will need to repair it (like you have done to your boat recently).

I expect the ballast system to work as designed because it has done so for almost 25 years now. I expect the ballast system to fail because my degree (such as it is) is in Physics and I'm a firm believer in the Second Law of Thermodynamics.

I check the water level every day because I'm a devout disciple of Murphy so I know stuff is going to break and and it's going to break at the most inopportune time.

I have confidence that the ballast system is working as designed because I checked it. I'm responsible for the safety of my crew, passengers, and vessel. If Roger MacGregor himself were on my boat and he told me the tank was full I'd still check the level and both valves myself.

I hope that helps.
Bill
2001 26X Simple Interest
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"If I were in a hurry I would not have bought a sailboat." Me
JamesToBoot
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Re: Ballast valve does not close - 26s

Post by JamesToBoot »

Thanks @OverEasy for reiterating the dangers of the partial ballast and going over the dangers of a partial ballast. That is good info. Knowing the consequences of a partial ballast is really good at driving home the point.

Thanks @Be Free for going thru your mindset and processes for checking the ballast. That is very helpful and I am likely to copy your methods for checking the system.

In addition, I may add a couple inches to the ballast valve w the garden hose the night before I leave for the lake to see if its leaking.

I'm sure I am being ridiculously over cautious (ex wanting to check the valve every 5 minutes, wanting to measuring to the mm the water level, wanting the gauge mod, or wanting to fill up those last 3 inches of space to the vent that are supposed to be there on the 26s), but I think going overly cautious on something new to me is a good default. I am sure time and experience will ease my overzealousness.

Does anyone have a different processes you run through when checking your ballast or before you hit the water?
-james
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'91 26S, fixer-upper, 55lb w 280ah lithium, need stern rail
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Be Free
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Re: Ballast valve does not close - 26s

Post by Be Free »

Absent a large and obvious leak, the ballast level is not going to change noticeably in five days much less five minutes. Check it when you start out and then don't worry about it unless something else feels out of the norm.

The level of the water in the tank may vary by an inch or more depending on how close to level the boat is when you measure it. The water level in my vent goes from "I can touch it" to "splashing out" depending on the attitude of the boat and the state of the water it is floating in. If it is not in one of those two states then the tank is not full. Measuring it to the mm is futile. You will learn what level is "right" for the current conditions and you will know when it is "wrong" and needs to be investigated.

The same goes for every gauge mod I've seen. The gauges were not designed to measure the difference between "touching" or "splashing"; they were there to measure "safe" or "unsafe". I can think of half-dozen ways to make a ballast level gauge and probably twice as many ways they could give a false reading. While it is not likely that a well-designed gauge would "lie" it is entirely possible that it could do so. For that reason, I'd still manually check the level before raising the sails regardless of what the gauge said.

Time and experience will give you confidence. It won't take you long to learn what the boat feels like when everything is right and when it's off you can stop and figure out what's wrong. If you have filled and checked the water level and both valves are closed then ballast is not likely to be the culprit.
Bill
2001 26X Simple Interest
Honda BF40D
"If I were in a hurry I would not have bought a sailboat." Me
JamesToBoot
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Re: Ballast valve does not close - 26s

Post by JamesToBoot »

Thanks @Be Free

Lost of good real life experience there. I figured I was just being paranoid, but like you elaborated, I'm sure it will ease w time & experience.
-Read and do the manual.
-Inspect the equipment.
-Learn from others experience.
-Remember Roger made a good boat.

I am excited.

We pulled the boat outta the shed today and put up the mast again... for the experience. Valve is still holding the inch or two i put in the other night.

It was a good time hanging in the yard w the fam. Started work replacing transom backing plates that are rotted... But that's for another tread.
-james
Novice Sailor
'91 26S, fixer-upper, 55lb w 280ah lithium, need stern rail
Cruising Grounds: Lake Murray, youtube
JamesToBoot
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Re: Ballast valve does not close - 26s

Post by JamesToBoot »

Update on the fix:

Haven't seen any drops or wet ground. Pulled it out to go sailing today and emptied the couple inches I had left to test.

Seems the fix has worked well.
-james
Novice Sailor
'91 26S, fixer-upper, 55lb w 280ah lithium, need stern rail
Cruising Grounds: Lake Murray, youtube
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Re: Ballast valve does not close - 26s

Post by JamesToBoot »

So... First time at the lake yesterday...

That is very unsettling unscrewing a valve and watching water rush into your boat...

I first filled it on the trailer. Checked it again at the dock and it wasn't full so I tried it again. Guess the boat wasnt resting fully in the water on the trailer.

Good stuff to know. Scary as mess your first time.

Saw this rv poop tank gauge. Has anyone mounted something like this in the vent hole you stick your finger in to see if the take is full:
https://www.amazon.com/Camco-Prevention ... 26&sr=8-20

Might be helpful and put your mind to ease in wavy seas when you want to check the water level but don't want to risk water pooring into your boat?
-james
Novice Sailor
'91 26S, fixer-upper, 55lb w 280ah lithium, need stern rail
Cruising Grounds: Lake Murray, youtube
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Re: Ballast valve does not close - 26s

Post by Russ »

That's an interesting device. I've never seen it before. From what I can gather, it allows venting until the tank is full. Looks like maybe it has an indicator to tell when full. I don't know that I would trust it as much as my eyes. A partially filled ballast tank can be dangerous.

There have been several mods posted on this forum for this. Some quite interesting and electronic sending an indicator to the captain in the cockpit.

It is alarming to see water coming out of the vent. Rest assured, there are zero reports of flooding from it.
--Russ
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Be Free
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Re: Ballast valve does not close - 26s

Post by Be Free »

It looks like it would work if you can come up with a way to mount it. Sticking your finger in the hole works too!

We need details on that first trip! Any pics?
Bill
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Re: Ballast valve does not close - 26s

Post by OverEasy »

Hi JameToBoot!

Interesting indicator!
Several folks on tge forum have tried a variety of approaches for ballast tank indicators as Russ has mentioned.
Some have used a cork float and flag on a wire or rod as a visual.
Someone tried a stepped piece of plexiglass that when inserted into the tank changes from whitish to black as water contacts tge steps.
A couple have rigged up capacitance gauges and readouts.
At least one may a float and contact switch arrangement which is sorta my favorite as it’s pretty straight forward Yes/No indication.
Currently I’m using the the wooden insertion dipstick indicator to replace the finger in the hole method.
When I get spare time after getting the current To-Do-List whittled down I’d like to possibly work out the float/contact switch approach.

Best Regards,
Over Easy 8) 8)
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