leaking boiler check valves

jjtjr Thu 21 Dec 2017, 10:34 am

Since I installed a water pump pressure gauge I can see if the pumps are working correctly.( see my you tube on this subject). When i started to use the car again I noticed the pump pressure gauge was not showing the boiler was filling so I started to troubleshoot the problem. What was found was the leaking check valve was letting steam and boiling water (back feeding) into the pump output tubing that feed the boiler, the back feeding boiling water was causing the water to flashing into steam and there by the pumps not working correctly.

I posted this on another steam forum. Having some problems with the boiler check valves. it appears the check valves are leaking. opened the water feed to the boiler and fired the boiler and had some water and steam flow out which means there leaking. The ss balls look good can't see the seats. Tried tornel balls from McMaster which worked for awhile but the steam damaged them. This may be of some help with our cars

This was the reply from two guys

For our 100+ year old Stanley Steamers, for the boiler feed water check valve, I use the stainless steel balls from McMaster Carr. Our boilers run at about 550 pounds steam pressure and at about 600 degrees F. Your boiler feed water check valve seats have to be lapped in with a fine valve grinding compound like what is used in lapping in IC engine poppet valves. Braze or mount a new stainless ball to a piece of round stock so that you have a mandrel to twist so that you can lap the stainless ball against the seat. When you eventually have a good clean ball seat, the boiler's feed water check valve will hold against the boiler's pressure quite well.

With an economizer which I run on Tugboat and Locomobile, when not taking on feedwater and the bypass partially closed, pressure built up in the economizer would occasionally blow all of the water out of the feed pump circuit back through ball checks, swing checks and United spring checks. The only check valve I've found that is 100% reliable, is the Stainless bodied Apollo soft seat check valve.

Like this one, it doesn't say Apollo, but it is.

I will be doing both of the above.