The Biggest Mamod Steam Engine Restoration Ever

Back in April, I was asked through to do a restoration on an early SE2 engine. I am proud to say that I have completed the restoration and this is my story behind, what I deem to be, the biggest and hardest restoration I have ever attempted to do.

I was first sent photos of the engine. As you can see, it was in an awful state. To go through my analysis of it below:

  • Everything was corroded by rust except the brass work as brass doesn't really rust but tarnishes.
  • The boiler's threads had all gone with the end plate gone too.
  • Exhaust piping is not there.
  • Piston is not there.
  • Water level plug, whistle and safety valve also not there.
For this reason, as well as repairing parts, I needed to buy quite a few parts for this restoration!

My main concern, before anything, was the state of the boiler. I needed to fix the boiler and make it safe for use. For this reason, I had to resolder every thread in the boiler and fit a new end cap on. This meant I had to buy quite a lot of parts which can be seen below.

The end cap came without a hole to put the water level plug thread through. So, I had to make that hole using a drill, solder the thread in and resolder the threads on top of the boiler too. If you are re-soldering the boiler, make sure you use flux to make the area you are soldering as clean as possible. Although most solder wire comes with flux in it already, I still apply flux manually to make sure. After fixing the boiler, it came out looking like this:

As you can see, everything is there now! The only problem with the boiler now is visually: the solder, to make sure the solder has filled in every gap, has over-run slightly. Therefore, I had to rub that down with some memory paper and shine the boiler too. 

That's one problem down, another several to go! I looked next at the parts that needed painting since they should be relatively easy. When restoring, you want to keep as many original parts as possible to make it as authentic as possible.

To restore the painted parts, I used memory paper, wire wool and even an angle grinder to remove as much rust as possible from the surface of the painted parts. The problem with this is that even if the parts are smooth and look as if they do not have rust, you will not have cured the part of rust. Even the slightest spec of rust will spread like a virus under the new layer of paint leaving you at square one again. For this reason, I had to use rust remover which cures the rust by de-oxidising it (or something like that) to make sure the rust will not spread. This can be seen below on the engine bracket which looks a rather dirty colour. However, this is only because the rust that was on there has been cured.

When it came to the base of the engine, I chose to spay a few layers of primer on it, let it harden, and smooth of any obvious lumps. In future, I should have used red primer although this doesn't matter really as I sprayed red paint over the top of it anyway.

Imperfections on the primer's paint surface can be seen in the bottom left corner. 

Even after smoothing the primer, there were still marks over the surface. This was due to the fact that the corrosion from the rust caused the base to become quite lumpy. Therefore, I looked to spraying it again with primer and smoothing it. However, there were still small imperfections over the surface! After talking to a few friends, I decided that I couldn't do any more: I was being extremely picky and had to move on.

Here is the first layer of red paint being applied to the SE2 base..looking good.

At the same time as painting the base, I decided to paint the other parts too. If you don't know what colours to use, you can find out here.

The flywheel being painted the same colour red as the base.

Here is the engine bracket and firebox being painted.

Another problem I encountered with this problem was the deadline for this restoration to be finished. Usually, if I am restoring an engine, I will let the painted parts harden for a few weeks so they do not chip if knocked around etc. However, I didn't have that much time to wait. After a few days of leaving the painted parts to harden, I started putting them together.

Although you should use hollow rivets when connecting the engine bracket the base, I used normal rivets as they provide a much stronger hold than hollow rivets (and I think they look nicer too). After this, I could then connect the crankshaft and flywheel together.

A problem I had, which I have with most engines, is the river to the right of the flywheel (in the second picture: the right rivet). It is always so difficult trying to fit it which is why it is slightly raised in the picture. It is mechanically safe but, from a visual perspective  it could have been better, However, the trouble of taking the rivet out and replacing it would have far caused more problems than to just leave it. So, I left it as it is.

I could now fit the safety valve, whistle and water level plug onto the boiler which, to my joy, fitted perfectly.

This was when I encountered my next problem. The crankshaft connects the piston to the flywheel. Therefore, it is an important part to the engine which needs to be smooth to ensure as little friction between itself and the piston. However, it was extremely rough from corrosion as shown below.

I had to change this otherwise the engine would not work. Another set back which I hope would be the last! After fixing this problem and replacing it, I put every part of the engine together.

It's a beautiful engine isn't it. You might have noticed a few differences to the typical SE2 engine:
  • The flywheel is brass. This makes clear that this engine is very old.
  • The base is flat instead of stepped up. 
By using Mike's steam engine's collection I found that this was an early 1950s engine which would have had a brass boiler band (which is why I brought a brass one instead of chrome).

To complete the engine and send it off, I just had to start the engine and make sure it runs! Unfortunately, it didn't. The boiler was completely safe from pressurise testing it by itself where there were no leaks at all. Therefore, the problem was with the piping and piston. After many times steaming up on fuel and compressed air, I found the problem was that the copper piping was pushing the piston at an angle which was making it hard to rotate. Therefore, by simply correcting this, the engine could run.

Here, the engine can be seen running from the blurred piston and cylinder. However, you might notice that the transfer has changed. Why? Well, the problem arose because of the corrosion from the firebox. The firebox was the worst part when it came to the amount of corrosion it has had from rust. This made the firebox much thinner than it originally was. For this reason, it was not as good at keeping the heat away from the transfer. This meant the first transfer simply bubbled off. The second transfer (which is pictured above) also bubbled off.

This was really annoying. I couldn't simply take the transfer off as it might take the paint off too and I didn't have enough time to repaint the firebox. So what I did was buy another transfer and give instructions to let the transfer become accustomed to the heat so that the transfer can thermo-settle and hopefully not bubble. To do this, the engine will need to be steamed up at low temperatures first and slowly increased.

Either way, here is the finished engine!

It is a real achievement for me to complete this restoration which I am very happy and proud of doing. What more, as I give a proportion of the earnings to charity, there will be £20 going to the Royal National Lifeguard Institute charity since that is the chosen charity by the person who wanted me to do this restoration, Dave.

Before I finish this article, I would like to think Dave for giving me the opportunity to restore this engine. It was tough but worth every minute!