What is this in my V berth

[finding41]

Today I set out to sand the bilge areas of my 1988 Macgregor 26D in preparation for painting. What I found up front was some bad patch with a cut out area under it. I think. Not to sure. There also are 3 bolts with nuts on them protruding through from the bottom up. All this is where the water ballast is supposed to be.
I pulled out the bad patch and found the cut away spot that's a yellowish color? Kind of looks like there are 2 screws, one on each side..? I took a video of the removal of the patch.
It is on YouTube; finding41 is my channel. There is some more sailboat mod stuff there too.

 

[RichH]

Thats a 'blow out patch'. Its put there so that when the sea state conditions get sooooo rough that the patch automatically comes out and the water then filling the boat helps to dampen down that 'violent motion' feeling ... for awhile. :-o <big grin>

Looks like someone 'plugged' a former 'sensor hole' and forgot/ignored to taper back the edges (12:1) of the 'hole' so that any hull flexing cant possibly break the roving/cloth on the new 'patch'. That 'patch' was probably laid up with cloth cut exactly to fit inside the squarish hole and 'end-butt-against' the non tapered hole and with a single or two layers of cloth to cover inner surface of the surrounding area; the resin rich 'butt joint' and the thin cloth used to 'seal it' has apparently fractured.

Obviously and if you agree, that 'patch' has to come out and this time the 'hole' properly tapered and this time with a 'not-so-resin-rich' amount of epoxy or polyester. If you dont 'fix' the hole, Lake Ontario will probably do it.

 

[finding41]

So It is suppoased to be there? I haven't seen or heard of them before.. Well I flared the hole and have prepped everything for a patch. Maybe tomorrow. I have to get some cloth to go with the resin I have.

 

[RichH]

So It is suppoased to be there?

Maybe you misunderstood my *joke* .... that cracked ineffective repair is more than dangerous and really should be totally repaired, correctly.

 

[finding41]

OH. Ok. I am going to repair it and did all the prep today. What is it though? What kind of sensor would be in the ballast tank? And the 3 bolts? I just wiped everything down in preparation for the patch and then paint. I might just pop a hammer through the old patch and take a look at what is inside the ballast tank. Maybe I should get the rusty bolts out. (I just don't want to fire up the grinder again. Its not so much the mess, its the itch.)

Here is a picture of it ground and washed.

 

[WayneH]

OK, First, I know NOTHING about Mac 26's. With that said, here's my take on what I see in your picture.

I think the PO had a "rattle" near that spot. You said you might pop out the patch and look inside the tank. What I thought of when I saw the picture was this. The hole is the access plate for the bolts so you can stick your hand and wrench in there to hold the bolt heads while tightening the nuts from the outside. And I see what "look" like pop rivets to hold the patch in place while the resin for the patch sets up.

You might want to pop the patch just to see WTF is under those bolts inside the tank. So, was the previous owner a used car salesman?

 

[MrBill_FLL]

where EXACTLY is this patch?

(I have a 88 mac D, and have been in the v berth. never saw anything like this.)

 

[finding41]

It's in the V berth first hole from the head. Right in the middle of the ballast. A PO has cut the hole bigger, I think to about Coleman cooler size. The bolts don't make sence as there isint anything attached on the top side of the ballast tank.
I didn't get time to knock a hole today in it today. Tomorrow for sure.
I have a feeling that I'm going to be doing some bolt grinding off....

 

[MrBill_FLL]

so you have 3 bolts going into the ballast? and a patch?

or are those screws and washers? could it be someone wanted to put nuts or backing on the bolts or some backing plate and they needed access to the bottom?

I see there are pop rivets to hold the patch in place.

whats weird is that is very very thin glass. and shouldn't really have anything attached to it.

the other thing is it could be a factory access point when building but I doubt it.

I would just glass it all over again heavy. its very thin and more glass would help hold more weight.

 

[finding41]

Mr Bill. I did remove a very thin patch that was 3 layers thick. Less than 1/8" thick.

 

[MrBill_FLL]

That whole ballast 'cap' top is only 1/8" thick. it flexes with water in it and sailing. like a waterbed.

I cut my vberth for a cooler, but added 2 layers of mat and thickened glass. its still VERY soft. (cooler rests on the ballast cap).

whatever it was, needs to be watertight, or it could be a big problem.

 

[finding41]

Oh the things one can find in the ballast tank. Any guesses.....I'll let the pictures tell a story. A very scarey story with dubious characters!
First the two main characters...
2nd, the setting...
3rd, there offspring...
4th, the damage...
5th, the movie on my you tube site. finding41

 

[finding41]

Unknown horrors in my ballast!

Any ideas what is going on in my ballast. I have seen pictures of the boat in production and this doesn't look like its supposed to be there. I mean the hump towards the front. It seems to be opposite what it should be. ( A natural V shape going forward.)
I cant see rocks getting sucked in from flooding the ballast and the rocks in my hand are too big to fit in through the air hole by the ballast inlet valve. Does anyone know if they would even fit in through the fill hole on the bottom? Then the other gravel in between the top of the hump and the top of the ballast...?
I took a closer look at the patch. It seems to be a piece of fiberglass with a thin coat of paint or gel coat sandwiched inside it. Who ever installed it didn't do any preparation in the way of sanding or tapering the edges.
I'm at a loss to what this modification is or why it is. I'm going to see if the factory has any idea what this is.
I haven't closed the hole yet. kind of want to know what is going on here first.

 

[r.oril]

Yuck!

Oh the things one can find in the ballast tank. Any guesses.....I'll let the pictures tell a story. A very scarey story with dubious characters!
First the two main characters...
2nd, the setting...
3rd, there offspring...
4th, the damage...
5th, the movie on my you tube site. finding41

That's nasty!
I have a pvc wand that I use to clean out the ballast tank after sailing. I plugged up the end, drilled holes in the pvc and added a hose connection. Works pretty good. Haven't seen any thing but water coming out as I spray the inside.

Mikes email captmike@macgregorsailboats.com

 

[finding41]

How do you get the pvc wand in the tank? I have a big hole I could use in my V berth.

 

[finding41]

Thanks for the email Bob. He got back to me quickly. "unknown patch".
I cant figure how anyone could get in there and put a patch or hump thing in without the boat being taken apart. I mean total de-lamination of the inner floor and hull. (during assembly?) Or If a hole was cut in the bottom of the hull and gain access that way...?? Some type of accident?? Its not looking like the hull was damaged or fixed from underneath. I'm going to try and borrow a snake type camera and see in a bit more.

 

[finding41]

Ha. I got it. I found out about the patch in my ballast tank of my 88 26D. Concrete covered with fiberglass! It must be a PO mod. (Some times there isn't an answer for why.)
Well the hump under the patch is concrete covered with fiberglass...? Additional ballast I guess. I decided to drill into it and see what it was as I'm going to have to patch it up any way. The bolts must be there to stop the concrete blob from sliding further back into the ballast. Kind of like anchors. That helps explain the gravel and the loose resin on the bottom of the ballast tank.
I'm going to leave it there for now. I was/am planning to put my batteries under the V berth for a bit extra weight up front. ( I have read that it helps with balance.)
Take a look on my YouTube channel "finding41" to see the exploratory surgery I preformed to determine it was concrete.
Thanks for the help all!