How to get a mamod steam engine going

Mamod Steam Roller

Moderator:Moderators

Feb 10, 2011 #1 2011-02-10T20:20

I am the proud owner of a 1975 (I have been told, wouldnt know how to tell!) Mamod Steam roller.

This is my first ever mamod and am after some tips on getting it running.

Obvious things missing were a chimney, a burner, a pipe and a scuttle.

I believe this model has a reverse lever and therefore 3pipes, 2 exhaust and one feed i guess? I think the reversing exhaust is missing.

I improvised a burner using a (slightly crushed) tea light with cotton wool and meths. Crude, but it works; and a couple of minutes later I was rewarded by a hiss of steam. WOW!

I added some oil also and was rewarded by a couple of revolutions backwards.

I do have some problems however, at first steam was hissing out of everywhere. I replaced the o-ring on the water level plug and on the safety valve and things got better.

I can still hear a pronounced hissing though, hadn’t realised there were two o-rings on the safety valve, the top one under the sprung relief lid (mushroom?) is quiet deteriorated. Is there a way of changing this or is it a new valve?

Any other info people can provide will be much appreciated. I’ve had a quick look around the forum and there are some great projects out there!

Anyway, some pictures.

Thanks,
Rich
How to get a mamod steam engine going
How to get a mamod steam engine going

Mamod SL1

Moderator:Moderators

Sep 10, 2015 #1 2015-09-10T00:58

Hi Guys,
I’ve recently built a small 45mm garden railway, and have acquired a 45mm SL1 to run on it.

How to get a mamod steam engine goingmamod1 by Peter Michalak, on Flickr

The loco has been re-wheeled with IP Engineering steel wheels, an in-cab regulator and high pressure safety valve, Goodal filler valve, and a dead-leg lubricator. Its also been fitted with a linkage to operate the reverser from inside the cab.

It hadn’t been run in close to 10 years, so I sprayed the loco with WD40, and cleaned it all up, then re-lubricated it with steam oil and light machine oil as required, filled the burner and away it went on blocks.

It has a few issues, and I was wondering if anyone can assist me.

As soon as it gets put on the tracks, it moves just a few feet, then stalls – there’s no real gradients on the line, and the safety is lifting, even when it stalls.

I noticed a huge amount of water and steam escaping from the drivers side piston, which makes me think there’s an issue with that cylinder – to the point where after just a few minutes, the loco’s out of water and I’ve had to drop the fire. Is there a way to refurbish these cylinders or are new cylinders needed?

At the same time, the loco’s burner (a 3 wick variety) seems to chew through metho like its going out of fashion. After less than 5 minutes, fuel is having to be re-filled, as the wicks are rather short, i’m suspecting this may have something to do with it?

Also, i’m sure the Goodall valve isn’t meant to leak steam and water from it is it?

I’m new to the live steam side of things, so any advice here would be greatly appreciated.

Sep 12, 2015 #2 2015-09-12T11:54

Peter, you can buy upgraded cylinders from Roy Wood Models. Well worth the cost.

The Goodall valve shouldn’t leak steam. If it is the type with a piece of silicone tubing on it, the tubing might need to be replaced.

Check the wicks are packed fairly tight in the burner. If they are loose, meths may be spilling out. You don’t want that as it’s a recipe for starting a fire.

What oil do you use in the lubricator? It has to be proper thick grade steam oil.

Sep 14, 2015 #3 2015-09-14T00:58

Hi Busted Bricks.

The Goodall valve is the type with the silicone tubing. Is there a particular type of tubing that I need to use (ie that can withstand high temperatures?) and what diameter do I need?

The wicks are very loose in the burner – I experimented with some cotton lamp wick yesterday, which improved the metho usage, but didn’t provide sufficient heat to keep the loco on the move – it stalled on multiple occasions while regaining pressure.

I live in South Australia, so don’t have access to the cottage industries to provide spares for live steam loco’s – what material can I use for the burner wicks – I read somewhere that you can use stainless steel mesh??

I’m unsure of the oil, however the gentleman who sold the loco to me, supplied a nice big bottle of the stuff – nice and thick, like treakle.

Sep 14, 2015 #4 2015-09-14T02:47

Always searching for the next basket case.

Sep 14, 2015 #5 2015-09-14T02:59

For silicone tubing do a search on eBay. You can get it from model steam suppliers (who charge the earth for it) or automotive and food industry suppliers (who don’t). Comes in all sorts of colours including clear.

To work out the size you need measure the diameter of the part on the Goodall valve it sits on and then look for tubing with an internal diameter 1mm – 2mm less.

For lamp wick, try to get a wick with a nominal diameter slightly larger than the hole in the burner you are pushing it into. Lamp wick is not expensive so it should not “break the bank” if you find you have to get a few different diameters to achieve the best results.

While you are on the Forest Classics’ website you may like to have a look at their ceramic burners. 😀

Sep 15, 2015 #6 2015-09-15T06:22

HenryArtist – is there a type of lamp wick I should be looking for? Any that are better than others?

Flyish – I checked the back-to-backs on the wheels, and they were in gauge.

I managed a semi-successful test run on Sunday, however after less than a lap the loco stalled while pressure built up (my track is less than 20 metres long, and rises less than 15cm in height)

Sep 15, 2015 #7 2015-09-15T14:06

Water refill valve – Your type uses silicon tubing. The secret is to get some tubing that has a thin wall thickness, otherwise the valve will not fit back through the 1/4″ boiler insert. I use thin tubing which is used for the fuel clunk in a Radio Control model’s fuel tank – appears to be 4mm outer diameter with a 0.7mm wall thickness.

Wicks – Some traders sell magic/super wick material, but you can pick it up easily (& cheaper) on eBay as it is sold as Wood Stove door rope. It has a ceramic content which after a couple of burnings will effectively seal around the top of your burner’s tubes. I cut mine oversize initially, then once it has sealed around the burner’s tubes I trim it to the operational height (approx 4 – 6mm above the tube).

Leaking Cylinder – Where is the leak coming from? If it is around the piston rod then the end cap has worn out and there are no replacements available. If it is from the back of the cylinder or back plate then it could be either a function of weak cylinder pivot bolt springs, or your wheels/coupling rods are not free running enough and causing a restriction.

You should be able to pull the piston rods off the coupling pins on the driving wheels and stow them out of the way. Then you can see how free running your loco is by giving it a push along your track. If it does not move much then I’d suspect those IP Eng wheels. They are fitted using a nut retained bearings which are very intolerant to any slight misalignment. I’ve also found it is beneficial to clean off the axle ends behind the wheels where these bearings act by using some brasso soaked fine wet & dry sandpaper.

Not everything is perfect and from time to time things need a bit of work to fix the little problems that occur.

Mamod is no exception and no model will be without its issues but it is important to know what to do when something goes wrong. Steam models can create numerous problems and as a good engineer it should be your role to fix them when they arise. Whether it is a straightforward task of simply replacing a part or cleaning out the engine or a more complex issue, it can be wholly rewarding for you to do it yourself.

Should you encounter any complex problem then Mamod is on hand to see if it is fixable by sending it back to the workshop. However, less complicated issues can be resolved at home with a little elbow grease, the right knowhow and a lot of patience. Obviously a model breaking down is the last thing anyone wants so you will want to get it back up and running as soon as possible.

Here are some solutions to fixing the most common problems with Mamod models.

Melted sight glass

Sight glass can melt from time to time but it can be resolved. Firstly you will need to order a new part from the Mamod factory which will include a new Perspex sight glass and a rubber seal. Unscrew the original screws and remove the melted sight glass, be careful when doing this as you want to avoid damaging the remaining paintwork on the boiler.

After removing, clean thoroughly to make sure all the remnants of the former sight glass and rubber seal have been removed. Place the new part on the clean surface and put in the new Perspex making sure the plastic protective coating has been removed, then simply screw in place.

Falling pressure in the boiler

You can carry out a number of checks if you losing pressure in your boiler. Problems can range from a leaking whistle to the safety being screwed in too tightly to a worn cylinder. By carrying out a few basic checks you can identify where the problem has stemmed from.

A leaking whistle can allow steam to escape and the pressure to fall and will only need to be oiled to get it back on track. If the safety valve has been screwed in too tightly then simply undo it and re-tighten to finger tight and no more.

Steam can leak from other areas such as copper pipes which may require re-soldering, if this is the case then send the model back to Mamod. If it is the cylinder then it will most likely need replacing while flywheel just need to be realigned to solve the issue.

Sticky cylinder

A sticky cylinder can prevent the model from moving. It is quite a common problem but can be resolved fairly easily. It usually occurs because the toggle spring is not working properly and it can get stuck. This means the cylinder is unable to move in the way it wants.

To fix this, simply pull the cylinder away from the engine face a few times to release the spring and then remove any visible dirt. Make sure it is properly oiled to avoid the problem happening again in the future.

Mobile engine producing steam but not moving

This can be one of the most frustrating thing for modellers, everything seems to be running smoothly but the model won’t move. This can be a result of certain element of your engine causing friction and the time delay between the boiler reaching pressure and the flywheel to reach a working velocity and thus the engine starts to run.

To fix this raise the rear drive wheel up using blocks then steam up the boiler as normal. Once working pressure is reached, spin the flywheel but keep the rear wheel off the floor and then wait for the flywheel to real a good velocity. Then place the rear drive wheel on the floor and push it forward, this will give the flywheel sufficient time to get the engine running.

Running a steam engine on Air?

Moderator:Moderators

Jun 02, 2010 #1 2010-06-02T17:32

:help:
I have seen a couple on the forum saying they are run on air, and being a ‘novice’ at steam still I was wondering how it is done?

e.g.
is it foot pump with one of them adaptors, a compressed air machine or campressed air can?

and how is it set up?

Many Thanks :thumb:,
Tom 😀

Jun 02, 2010 #2 2010-06-02T17:52

I think most of us use an ordinary compressor with a regulator.
Some people have success with aquarium pumps if the engine is a good one.
The best, IMHO, would be a small airbrush compressor as they are very quiet.
I have a small compressor from a dehumidifier which works well and is quiet enough to use in the house. A fridge compressor is also ideal.

Jun 02, 2010 #3 2010-06-02T18:00

Bugsy wrote: I think most of us use an ordinary compressor with a regulator.
Some people have success with aquarium pumps if the engine is a good one.
The best, IMHO, would be a small airbrush compressor as they are very quiet.
I have a small compressor from a dehumidifier which works well and is quiet enough to use in the house. A fridge compressor is also ideal.

That is a good idea. fridge compressor. never thought about that one!.

A cheap one can be found at any metal scrap place.

Jun 02, 2010 #4 2010-06-02T18:04

I have a workshop compressor with a 24 liter tank (you can get them with much smaller tanks) it makes noise when i am filling the tank up but as soon as the tank is full it goes off and is completely quiet.
You can buy or make the adapters to connect to your engines (cost about 3-4 ) then you can run your engines with air.

I must say that steam still beats it in terms of fun. I mainly use air just for quick tests or during repairs when heating up the boiler will just delay me or make the parts too hot for me to touch .

To Mr. Stuart Webmaster guy, you couldnt possibly sitcky this post so that if people dont add new tips for a while then it wouldnt get drawn to the archives of time.

Either way, im still a noob to restoring things so i (and alot of others i presume) would really appreciate it if old hands like cummings would post a few instructions.

bradfirj92 wrote:
. it if old hands like cummings.

Your other thread has a few tips, if there’s any you need in particular, I may be able to help.

____________________
I’m a lumberjack and I’m ok,
I sleep all night and I work all day

He’s a lumberjack and he’s ok,
He sleeps all night and he works all day.

bradfirj92 wrote:
To Mr. Stuart Webmaster guy, you couldnt possibly sitcky this post so that if people dont add new tips for a while then it wouldnt get drawn to the archives of time.

That would be a good idea, I would PM him though as I don’t think Webmaster comes down here that often. I don’t know, I’m sure he may be lurking in the shadows somewhere, just waiting to pounce.

____________________
I’m a lumberjack and I’m ok,
I sleep all night and I work all day

He’s a lumberjack and he’s ok,
He sleeps all night and he works all day.

My Basic Tip (when you say restore, I assume it is well used, probably with parts broken:

First of all, when you get your Mamod, is to clean it all up (see my other post). Buy a new saftey valve. Although not essential, I find it to be a good precaution no matter how ok the one it came with is. Do all the oiling and other stuff and try and get it to run. Only put one tablet in, and be patient and gentle, do not put on a drive band. At the first sign of something wrong (especially with the saftey valve), stop the test. Record notes etc. Then, scrape off all the paint with thin sand paper (this is assuming your doing a full strip down restoration). Always do this after test running as the paint protects the metal from damage through heat etc. Then, re-solder any joint on the piping if required, buy any spare parts required and I would advice the following accesories:

The pressure gauge will help with testing.

For painting, I would recommend car aerosel spray paints, do several thin coats and mask off carefully. I am going to paint my Mamod Traction engine to the standard colours but with a red and gold striped boiler. I’ll keep you guys posted.

____________________
I’m a lumberjack and I’m ok,
I sleep all night and I work all day

He’s a lumberjack and he’s ok,
He sleeps all night and he works all day.

Found out another tip for when you get your Mamod:

As a routine maintenance proceedure, fill the boiler with white vinegar. Leave it for about an 1 hour, and the drain the boiler completely and flush it a few times to remove all traces of vinegar. This is to remove build up on the inside of the boiler if you are not using distilled water.

NOTE: I have never done this trick so the time is probably very inaccurate, if anyone else does it, please report on it’s effectiveness.

____________________
I’m a lumberjack and I’m ok,
I sleep all night and I work all day

He’s a lumberjack and he’s ok,
He sleeps all night and he works all day.

Cummins wrote:
My Basic Tip (when you say restore, I assume it is well used, probably with parts broken:

First of all, when you get your Mamod, is to clean it all up (see my other post). Buy a new saftey valve. Although not essential, I find it to be a good precaution no matter how ok the one it came with is. Do all the oiling and other stuff and try and get it to run. Only put one tablet in, and be patient and gentle, do not put on a drive band. At the first sign of something wrong (especially with the saftey valve), stop the test. Record notes etc. Then, scrape off all the paint with thin sand paper (this is assuming your doing a full strip down restoration). Always do this after test running as the paint protects the metal from damage through heat etc. Then, re-solder any joint on the piping if required, buy any spare parts required and I would advice the following accesories:

The pressure gauge will help with testing.

For painting, I would recommend car aerosel spray paints, do several thin coats and mask off carefully. I am going to paint my Mamod Traction engine to the standard colours but with a red and gold striped boiler. I’ll keep you guys posted.

Why the new safety valve? If the old one is OK use it – we,re not talking massive psi here, no more than 15. Hence no need for a pressure gauge.

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A Mamod model steam engine TE1a with original booklet

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A 1970’s Mamod SR1 A live steam roller, comprising engine, steering rod, burner tray and driving belts

A 1970’s Mamod SW1 steam wagon, in green and red, with spirit lamp filler funnel and detachable steering extension

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A boxed Mamod Traction Engine T.E.1A

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A boxed Mamod live steam model roller, together with two shooting sticks

A Mamod steam tractor and wagon

A Mamod stationary steam engine

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A Mamod steam engine, with solid fuel tablet box and funnel.

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A Mamod style steam road roller, 32cms (12.5ins) long.

MAMOD TRACTION ENGINE LUMBER TRAILOR

A Mamod steam roller, with box and accessories

MAMOD STEAM TRACTOR

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A VINTAGE MAMOD TE1A STEAM TRACTION ENGINE WITH ORIGINAL BOOKLET

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Mamod live steam Roadster car; white body, without burner accessories or box.

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Mamod Boiler Pressures and SV blow off .

Moderator:Moderators

Aug 12, 2009 #1 2009-08-12T00:50

I’m just after some info here with my first Mamods. After putting a gauge on my SE3 i find it starts to spit about 20 PSI and wants to keep blowing off more and more as it climbs (duh) but i have never let it go past 25 PSI. (Just a test of the SV and meths burner combo).

What should i run this baby at just to be safe. I have been keeping it at 20 or less. during runs. and keeping an eye on the pressure.

I also would like to know if the MM1 would be the same. (no gauge though).

How to get a mamod steam engine going

Wilesco English Website

Aug 12, 2009 #2 2009-08-12T00:58

This winter, I’m going to do an experiment to see how high the pressure can get on a mamod boiler

I’m sure these boilers can probably handle 40 psi, but I would never let it get that high.

The “safety” valve doesnt relieve it of pressure?
A lot of the time the O ring sticks, that might be the problem.

Aug 12, 2009 #3 2009-08-12T01:06

How to get a mamod steam engine going

Wilesco English Website

Aug 12, 2009 #4 2009-08-12T01:24

The lifting pressure is supposed to be about 15psi I think.

I haven’t tested all, but out of the mamods I have run on both air and steam, to get the same RPM from air as steam, I am looking at about 20psi. But I put that down to lack of heat and things being a bit tighter? But going off your test that isn’t the case.

This is going off 2 gauges, one on the regulator, the other an aftermarket oil pressure gauge that I put on the line.

I rarely run them on air, and if I do it’s at a much lower pressure for slow speed and reaching 20 was just a test for me.

When running them on steam with the regular burners, I’d just let them run at whatever they go at.

The spring in the valve shouldn’t really get stiffer. Only thing I can think that would affect it is the thickness of oring at top of valve, or if.

Edit: Just checked my 2 mamod S/V on scales by pressing down. I know it doesn’t equal psi, but both started to open at about 8 ounce and just over 1pound for fully opened. My Steamco one opens at just over 1 pound and about 2.5 pound fully open.

There was a scale once posted here but I lost it. It showed how to determine a SV psi rating by using the above method on kitchen scales. Tony?? I think posted it?

You don’t have to always go looking for answers.
Sometimes you just need to listen.
Rick McCrank

Not everything is perfect and from time to time things need a bit of work to fix the little problems that occur.

Mamod is no exception and no model will be without its issues but it is important to know what to do when something goes wrong. Steam models can create numerous problems and as a good engineer it should be your role to fix them when they arise. Whether it is a straightforward task of simply replacing a part or cleaning out the engine or a more complex issue, it can be wholly rewarding for you to do it yourself.

Should you encounter any complex problem then Mamod is on hand to see if it is fixable by sending it back to the workshop. However, less complicated issues can be resolved at home with a little elbow grease, the right knowhow and a lot of patience. Obviously a model breaking down is the last thing anyone wants so you will want to get it back up and running as soon as possible.

Here are some solutions to fixing the most common problems with Mamod models.

Melted sight glass

Sight glass can melt from time to time but it can be resolved. Firstly you will need to order a new part from the Mamod factory which will include a new Perspex sight glass and a rubber seal. Unscrew the original screws and remove the melted sight glass, be careful when doing this as you want to avoid damaging the remaining paintwork on the boiler.

After removing, clean thoroughly to make sure all the remnants of the former sight glass and rubber seal have been removed. Place the new part on the clean surface and put in the new Perspex making sure the plastic protective coating has been removed, then simply screw in place.

Falling pressure in the boiler

You can carry out a number of checks if you losing pressure in your boiler. Problems can range from a leaking whistle to the safety being screwed in too tightly to a worn cylinder. By carrying out a few basic checks you can identify where the problem has stemmed from.

A leaking whistle can allow steam to escape and the pressure to fall and will only need to be oiled to get it back on track. If the safety valve has been screwed in too tightly then simply undo it and re-tighten to finger tight and no more.

Steam can leak from other areas such as copper pipes which may require re-soldering, if this is the case then send the model back to Mamod. If it is the cylinder then it will most likely need replacing while flywheel just need to be realigned to solve the issue.

Sticky cylinder

A sticky cylinder can prevent the model from moving. It is quite a common problem but can be resolved fairly easily. It usually occurs because the toggle spring is not working properly and it can get stuck. This means the cylinder is unable to move in the way it wants.

To fix this, simply pull the cylinder away from the engine face a few times to release the spring and then remove any visible dirt. Make sure it is properly oiled to avoid the problem happening again in the future.

Mobile engine producing steam but not moving

This can be one of the most frustrating thing for modellers, everything seems to be running smoothly but the model won’t move. This can be a result of certain element of your engine causing friction and the time delay between the boiler reaching pressure and the flywheel to reach a working velocity and thus the engine starts to run.

To fix this raise the rear drive wheel up using blocks then steam up the boiler as normal. Once working pressure is reached, spin the flywheel but keep the rear wheel off the floor and then wait for the flywheel to real a good velocity. Then place the rear drive wheel on the floor and push it forward, this will give the flywheel sufficient time to get the engine running.