The saga continues.
When I got back to the engine this morning, the studs were in there rock solid. If ever they need to be replaced, a couple of nuts on the stud, and then warm the stud up to cherry red, give it a few seconds, and it will be able to be screwed out. The heat will transfer down the stud and break down the threadlock joint.
The excess jointing goo was cleaned from around the bases of the studs.
I used two thick gaskets as they will withstand handling better than the thin ones for what we are doing, the joints will all be made correctly on final assembly. I am just getting all the mechanical bits done first. The first shim was followed by the steam chest, then the cover. The bores look scored in this shot, but they aren't. I put a bit of detergent oil down the bores to remove the last remnants of gunge, what you are seeing is the dirty oil being streaked up the bore.
Then two washers were put on each stud, followed by a nut. Everything was tightened down.
Excess length on the studs was then ground off, and the studs were filed down flush to the top of the nuts. One of the washers was removed from under each nut and then reassembled.
The cloth was there just to protect the engine from grinding dust and metal swarf. We don't want that muck going up and down in the bores.
So this is what it looks like now it is finished. About one thread protrusion from each nut, and everything looking nice and neat.
The gaskets will now be a lot more stable and blow resistant because of this work.
So next I turned my attention to just around the corner, the steam inlet manifold.
I was going to fit studs on here as well, but because they would make disassembly more difficult, I decided to use hex head screws instead of the slotted ones that were in there. They will allow more pressure to be put on the gaskets.
This brings me to this shot. I made a few more 5 thou gaskets for the flanges this time. They do look rather rough, that is because they were difficult to cut around on the bench, so they were left slightly oversized and will be trimmed up when held in their final positions.
So after cutting four screws to the correct length, the manifold was assembled onto the engine and the gaskets trimmed up to match. So that brings me to the end of the top end refurb until final assembly. So off to the next bit.
This is the steam control valve, that controls the entry of steam to the engine, giving basic speed control. It is this coupled with the reversing linkage that makes the engine go backwards and forwards at whatever speed you want the engine to run at.
Now there is a major problem with this bit. At some time in the past, the o-ring has worn (it has a flat on one side) and allowed steam to come out where the handle is. I tried today to remove the handle, and it won't budge. So it looks like someone came across the same problem about the handle, and thought that putting a shim in the bottom of the chamber would cure the problem by pushing the drum harder onto the o-ring. Unfortunately, that wasn't the case. What it did was force the drum to rub on the bottom of the flange, and because it seems the drum is made of bronze, it has worn the bottom of the brass flange. I noticed that when turning the handle, it got very stiff in places, whereas it should move freely in a full 360 degree sweep.
This is where I got to today.
So I have made a decision to repair this unit, I will have another go at getting the handle off, but don't hold out much hope. I might just cut the shaft just below the handle. By doing that, and making up a replacement flange to cure the damage, plus a different type of handle, I can cure the problem about changing the o-ring forever. That will then be a five minute job.
Bogs
