MacGregorSailors.com

Thanks for all the advice.
The boat is out, and I managed to pry the gate up with a screwdriver - the water came out easily, no big pressure, just like I was told by the knowledgeable Macsters.
In a couple of months, when I return to my hometown from Germany, I will proceed to unscrew the old valve and try to install the new one.
When I do, I will try to remember to post some pics of the whole process.

BTW- After I took my boat out I stuck my hand in there (if your hand can go in, it will come out) and found that the 4 mounting screws go through the transom thickness and out the back (into the ballast area) in a 2011 M. My finger resolution was not enough to tell if there are nuts there (well, I could get the scope out), but I doubt it.

So you would want to goosh some sealer back there too.

No nuts on the inside. When I re-installed mine I added self-locking (nylock) using a socket wrench with an extension so I could hold the nut and tighten everything up. It wasn't fun, particularly as I used 5200 and ended up getting it all over me as well. You could hire a midget with tiny hands to help out but persevere and everything should work out.

The factory had used the assumption that the four individual threads would be sufficient to retain the wastegate base against the low ballast water pressure - and I've not yet heard of a case where they have failed during normal use. I suppose you could envision a situation where a partly filled (ballast) tank could slosh and hammer it off but nobody's mentioned anything so far.
My addition of nuts was in conjunction with a valve mod where I needed to provide extra strength, as well as clearance for adding trim tabs to the transom.

Ross

Unscrewing the screws was somewhat tough - make sure the head fits the screw perfectly. I had to clean the heads with a sharp tool first. There were deposits of coagulated dirt, salt and god knows what else. Once I got a good grip, I was able to get them moving even by hand. One of them did require a small battery powered screwdriver.
That was the first part.
The second part was sticking putty knives into the crevices on the side of the valve body, in order to separate it from the transom.
Patience worked, and the silicone (3M 5200) gave way after 30 mins.
Third part - removing all the residue from the transom wall and the hole. Razor blade and a sharp, flexibel scalpel did it.
At the end, I sanded both the hole and the wall with a relatively fine sandpaper.
I was not able to find 3M in EU at a decent price, so had to order a tube from the US.
Once it gets here, I will get to attaching the replacement valve to the boat.
I will reuse the screws, since I was not able to find the same kind locally.

One problem I have encountered and have not been able to resolve:
the extension pull handle, when screwed onto the rod of the new valve and twisted all the way (to get the best grip) does not end up flush
with the transom wall, like the old one did.
Any ideas on how to solve this?

Thanks!

One problem I have encountered and have not been able to resolve:
the extension pull handle, when screwed onto the rod of the new valve and twisted all the way (to get the best grip) does not end up flush

Use loctite and stop when it is flush

richter372001 wrote:One problem I have encountered and have not been able to resolve:
the extension pull handle, when screwed onto the rod of the new valve and twisted all the way (to get the best grip) does not end up flush
with the transom wall, like the old one did.
Any ideas on how to solve this?

Thanks!

Use a lock nut on it. Thread it in almost all the way, but stop when your alignment is correct. Now tighten the lock nut down to the valve.

~Rich

Thank you, Rich. So, use the lock nut between the valve and the extension lever?