Before you can operate one of my marine boilers it will be necessary to furnish it with some fittings. I will fit these for you free of charge if you order them from me at the same time as the boiler. However, you may wish to purchase these from alternative sources, or even make them yourself, if you have the necessary tools and skill. Irrespective of where you source your fittings, a few words on mounting them may be of help.

 

What Fittings?

As a bare minimum a safety valve must be considered an essential fitting. It would be extremely unwise, not to say foolhardy, to operate any kind of steam boiler without fitting a correctly adjusted safety valve.

A water gauge should also be high on your list of fittings. Your boiler will be seriously damaged if the water level is allowed to drop below the top of the flue tube whilst the burner is lit. A water gauge will allow you to monitor the water level and take appropriate action before this occurs. Ideally the water gauge should be fitted with a blow-down valve to allow you to clear the glass when bubbles form in it.

A pressure gauge is a useful accessory although in the sizes normally used in models of this type (1/2" and 3/4" diameter) it can only be regarded as a rough indicator of boiler pressure. Model gauges of this size must never be used to set safety valves. This should always be done using a gauge of known accuracy.

To enable you to control the steam from your boiler, some form of steam valve will be necessary.

If you want to be able to keep your boiler topped up with water whilst it is in steam you will need to fit a pump of some sort. This could be a mechanical pump driven off your engine or a simple hand pump. The pump outlet should be connected to your boiler via a non return or check valve.

I can supply blanking plugs to seal any unused bushes.

 

Mounting Fittings

Mounting fittings on you boiler is very simple but there are a few points you should bear in mind.

Remember that the silver soldering process your boiler underwent during manufacture will have left it nicely annealed and very soft. The threads in the bushes are easily damaged and great care must be exercised to avoid over tightening or crossed threads.

A drop of thread sealer sould be applied to the threads, before screwing them in, to prevent leaks. I use Loctite 222.

With some fittings eg. water gauges, check valves and steam valves, it is important that the fitting is oriented correctly. That is, check valves should be upright, steam valve outlets must be on the correct side of the boiler for your engine and top and bottom water gauge fittings must be in alignment. Please do not attempt to do this by simply continuing to tighten the fitting until it is pointing in the right direction or you will surely strip the threads. There are several ways of doing this safely, soft copper or aluminium washers (you can make them yourself from empty drinks cans), fiber washers etc. The simplest way and the one I always employ is to use crushable copper washers. These are made from folded copper and allow over one complete turn to be made as they collapse down. With thread sealer on the threads and crushable washers, your fittings can be aligned extremely accurately and will not leak. I can supply 1/4" diameter crushable washers, suitable for all my fittings at £0.12 each.

When fitting water gauges it is essential that the top and bottom fittings are correctly aligned. There should be clearance all around the glass, it must not be restricted in any way. The glass can be cut to the correct legth by marking where the cut needs to be made, using a felt tipped pen. It can then be scored using the edge of a sharp triangular shaped file. One of the cheap diamond coated needle files is ideal for this but an ordinary carbon steel file will do if you don't have one. The glass can then be broken easily by hand. Wrap the glass in a cloth before breaking it to protect your fingers. Be very careful that you make the glass the correct length. When it is fully inserted into the bottom fitting, the top of the glass should just enter the top fitting when the gland nut is removed. Pay particular attention to ensure that the top of the glass does not obscure the water hole from the boiler. When the glass is the correct length it can be fitted with the gland nuts and silicone rubber seals. Take great care not to overtighten the gland nuts or you will break the glass. They only need to be little more than finger tight.