Since quite a lot of Westerlys are Bukh-powered, I hope this little tweak to replace the bolts securing the thermostat housing to the exhaust manifold on my Bukh DV20 might be useful to others.
I was fed up with the long bolts that hold the housing onto the exhaust manifold; the threads always got fouled up with corrosion products. On my Bukh, several have been heli-coiled, and so the pre- and post- winterising “little job” of taking out and replacing the thermostat was a pain.
Hence, I decided to replace the bolts with 6mm stainless studding, screwed fully down into the threaded holes in the manifold and secured with locktite, with stainless nuts on top. Now, taking the thermostat in and out is just a matter of undoing the nuts and lifting the lid, without disturbing anything else.
The studs were cut to be a bit longer than the bolts they replaced, but even so, one proved to be a bit too short, as the depths of the threaded holes in the manifold weren’t all the same. So, I had to cut a new longer one on the spot (fortunately I’d taken the spare studding down to the boat). That’s why one of the studs is longer than the other three- I wasn’t taking any chances the second time round!