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Author Topic: Jensen 20g basic questions  (Read 1314 times)


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Jensen 20g basic questions
« on: June 21, 2024, 11:34:06 am »
I am in the process of choosing my first steam engine and a few basic questions. Is a pressure gauge a good thing to get for the 20g? If using a compressor to help blow out the boiler would you remove the whistle (pressure gauge) and the blow off valve? Then hold the engine at an angle?
To lubricate the cylinder do you put oil at the exhaust and suck it into the cylinder?
Sorry for the basic and probably stupid questions but I want to make sure that I have an idea of how to take care of the 20g.
Thank you in advance for your help folks!


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Re: Jensen 20g basic questions
« Reply #1 on: June 21, 2024, 11:58:59 am »
A pressure gauge is nice but not necessary. I don't use compressed air to dry my boilers, (some do), usually a syringe with tubing attached poked thru one of the bushings. Make sure the tubing doesn't fall inside. Tilt to collect the water at one end, then suck the water out. I also leave the safety valve and whistle off for a while to help in drying.

Yes, you rotate the engine in reverse to suck oil into the steam chest/cylinder to lube. Don't need a lot and use steam oil.

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Re: Jensen 20g basic questions
« Reply #2 on: June 21, 2024, 12:12:21 pm »
Yes, a pressure gauge can be a very good tool to keep track of your steam production and consumption. However, with a Jensen 20, so long as your heating element is in good shape and you are not running the engine full bore, you are probably going to be maintaining adequate boiler pressure throughout your run. A pressure gauge can be something of a safety device too however, in that if you see the pressure suddenly start rising rapidly, it is most likely an indication that you are getting very low on water, which is always a bad thing to be avoided at all costs.

Perhaps the best way to remove water from your boiler is to suck it out with a syringe that has a flexible tube on the end of it so as to reach into a bottom corner of the boiler which is tipped just a little to move the water to that corner. It is good to use a compressor to blow out your steam lines and clear excess condensation out of your cylinder by giving the engine a few seconds of run on the air. I do not recommend trying to drain a boiler by inverting it in any way. Awkward, difficult and tends to put water where you don't want it, like up the steam line.

Another point to ponder when shutting down your engine for the day, is to blow off all residual steam, the whistle will work for this, and open up the boiler by removing at least one of the fittings on top, for which the whistle or safety valve will work for this part as well. With the boiler thus opened up to atmosphere, it will not draw a vacuum as it cools, with the potential for sucking steam oil back up into the boiler, which is generally NOT a good thing!

To properly lubricate your cylinder with steam oil (do use proper steam oil), use a hypodermic like oiler at the exhaust, and with the steam valve closed, turn the flywheel backwards from the direction the valve gear is set to, and you will suck steam oil into the "valve chest" and cylinder.

All questions are basic to those who already know the answers, and no questions are stupid for those who do not!!!

Good choice of engines in my opinion, and even better that you want to know how to take care of it properly!

Oh .... good job there Bret, you bet me to the punch with good answers and far fewer keystrokes!  ;c)
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Re: Jensen 20g basic questions
« Reply #3 on: June 21, 2024, 03:10:25 pm »
An aquarium air pump with flexible tubing works wonders for drying out a boiler.


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Re: Jensen 20g basic questions
« Reply #4 on: June 22, 2024, 01:12:40 pm »
When Im done running my engines, I dump the water out of the boiler while its still hot. The remaining heat dries the boiler right out.

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