In spite of the aluring heading, it really is a mundane question.

I am in the throes of final assembly of my Locosurrey and have the choice of 3 gauge glasses.
the first is the standard original type with the open glass.

the second is a new reflex type supplied by the wonderful people at Goolds (viewing window about 4 inches long)

the third is also a reflex type, with a klinger glass with a viewing window of about 10 inches.

Now, obviously the third, allows me to see the water level over a much wider range, (with the boiler only being 13 inches top to bottom)
but (a) is it necessary? (b) too large a heat loss? (c) unnecessary?

I obviously WANT to run the boiler with the correct water level, for which the Goold supplied unit would be fine, and I will be installing a try cock tower under the rear seat, but wonder if the paranoia I suffer, should the level fall blow the visible level on the smaller unit... would be substantially reduced by using the longer unit?

Could useres of smaller boilers, 14inch and 16 inch units advise me of the water usage levels (and the related effect on gauge glass levels), am I being overly
worried with a very gentle movement being the usual, or with the fairly small volume of water in the boiler does this mean that there can be a quick effect upon gauge glass level?

Regards,

Dave Hume

The shorter reflex glass will be more trouble free with its gasket than the taller glass would. The taller the glass, the more movement that you will have in the gasket from the different coefficients of lineal expansion from the heat changes. Also with the taller glass, because you can still see your lower water level, it will also allow you to run at a lower level in your boiler which is an unsafe practice. The operator figures since they can still see the water in the glass, then he is still safe and he continues to operate at that lower level. Operating in the lower half of the boiler will eventually bite him with a scorched boiler.

In any case you'll probably get more steam out of it by running fairly high in the boiler. The risk of hydraulicking particularly when the car is warmed up and the superheater hot is much less than the risk of scorching if running too low. Too high a level on my car is felt by the driver as a general sloshyness although occasionally a good dollop over is like having an afterburner and the car sets off like a rocket.

Mike

OK then assuming I go with the Goold supplied 4 inch new glass, what are peoples feelings about the height?

Exactly 1/2 way? ie 2 inches either side of the midpoint?

slightly higher? say 2 1/2 inches at the top and 1 1/2 below the midpoint?

I have always assumed the glass should be approximately 2/3 full, that is with marine boilers.

what is the car fraternities view?

dave

The Stanley fusible plug alarm system used three inch from the lower tube sheet as the mean low water level. I like four inches my self. Fire off.
You should be able to maintain water level with in two inches of operating level. Remember this is a false water level. This is a swell water level or based on how much steam your drawing from the volume of water in the boiler.
There are three water levels in a boiler.
1. Cold water level
2. Saturated steam water level.
3. Water level with the throttle opened at full speed.
Number three is what your seeing in the glass till you close the throttle, and the water level will drop to number two. You should know this distance. This distance varies and will increases as water is depleted in the boiler. In smaller boilers its much more noticed.

I am using 7-1/2 inch as an operating level with a 14inch boiler. 1-1/2 low and feed water bypass is closed
Rolly

Thanks Rolly,

that sounds like a plan, 2/3rds of the glass with the glass located at the exact midpoint.

Thanks to all

Regards,

dave.

Make sure you have a gauge blowdown valve within easy reach while driving - that way you can make sure at all times that the gauge is working.

Mike

I would dearly like to have one handy Mike, but as mine is a Surrey, the boiler et al is all under the rear seat, with muggins up front. This was regarded as a disadvantage even at the time, but yes there will be a drain cock at the bottom of the gauge as well as a test cock tower under the seat.
I anticipate many nervous months "learning" the characteristics of the car and steam system... eg how fast the level drops with various grades and road conditions.

thanks for the input.

Dave

Just pipe the drain cock to a valve poking through the floor by your heels in front of the seat - that works for me - give it a tweak open and shut and see the water in the gauge fall and then rise to the right level.

Mike

Hi Dave.
None has mentioned that it is wise to have a fall on the water pipes connecting the water level gauge, IE. if the gauge connections are short and go into the boiler almost direct it is not too bad but, if the gauge is some distance away and has long pipes the bottom pipe must not be horizontal, the reason for this is if you are "slogging" up a long hill the pipe will fill with condensation and give a false reading indicating water in the glass when in fact there is non or very little in the boiler , I KNOW I HAVE BEEN THERE. the problem was solved by connecting to the bottom of the boiler providing a steep slope on the pipe. good luck with your project Le Nelson