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Discussion Starter #1
I'd noticed that my 0-6-0 could quickly go from 40psi to 80psi while standing still if I wasn't paying attention, and decided to pop off the steam dome and watch the safety valve blow under "lab conditions".

I believe it's supposed to at least weep at 60psi, but I get nothing out of it until 80psi, and then a fairly weak blow.

Is there any way to tune these things like there is on the Roundhouse safety valves?

Thanks!
-Rex.
 

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My recommendation is that you install a WeeBee pop safety valve set to the recommended pressure for your locomotive. 80 psi sounds a little high, but I am not familiar with AML stuff. Popping off at 60 psi sounds more like it. You can get a pop valve from Jason at the Train Department.
 

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Carl's advice is spot on, the Wee Bee valves are precision devices. I have a collection of Accucraft pop valves that dribble and sputter, but most of them start a too low a pressure. Those I would take apart and slightly stretch the spring to try to get them up to about 50. I have never had one that held until 80. Have you taken it apart just for fun and made sure there is no binding going on, lube the O ring, etc? Can't hurt unless you lose the C clip...

Jerry
 

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Discussion Starter #4
Carl's advice is spot on, the Wee Bee valves are precision devices. I have a collection of Accucraft pop valves that dribble and sputter, but most of them start a too low a pressure. Those I would take apart and slightly stretch the spring to try to get them up to about 50. I have never had one that held until 80. Have you taken it apart just for fun and made sure there is no binding going on, lube the O ring, etc? Can't hurt unless you lose the C clip...

Jerry
Safety valves are one of those things that I have not attempted to mess with. I mean, I assume it's popping at 80 because the pressure gauge reads 80 (well, stops at 80). I figure the pressure gauge is less likely to be off by ~20lbs, because the loco does work well at an indicated 40lbs+.
 

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There is always the variable of is the pressure gage accurate? Do you have another loco you could swap out a gage? Or better yet, a home air compressor with a decent gage, take off the boiler fill nut and use your air compressor's blow gun, the one you have with the rubber tip, set the compressor for 40 psi and press it into the filler hole and see what your loco gage reads at that and other various pressures. Good way to check things. Also see when the valve pops. Don't go over 80 or so

Jerry
 

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Discussion Starter #6
Ordered a WeeBee, it was on the list anyway. Then we'll see if the gauge is borked.
I've a feeling it might be, because the "sweet spot" for this particular locomotive is very small, she tends to feel under-powered for more than half the run, given careful management of the water, burner, and pressure. <-- I find this odd given this locomotive's reputation as a very solid puller.
 

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rexcadral, you/ve herd right, that locomotive is a great puller, and very forgiving, mine even allows steam to the tender to warm the gas. I was at a steam gathering several years ago where an Aster loco had pulled a 30 car train, and one even had a squeaky wheel set. After it was done I coupled my 0-6-0 to the string and it walked away with it. I was shocked. As you know it is a heavy little beast so all the weight is on the drivers. I am very sorry to say, I lost the video when my Dell crashed, I lost a lot.
 
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