Author Topic: Saftey Valve pop on Welsco, Jensen etc (Read 189 times)

Bobsmodels · « **on:** February 04, 2023, 01:53:40 pm »

Hi

Just curious about the pop off pressure on say a Wilesco d22. From the pictures on the site it looks like around 20 or 22 PSI. Anyone have an idea of what is common?

I need something real small around 30 psi and I wondered if I could play with the spring on one of these to get it about there, boiler is of similar size, low output.

Thank You

Bob

RedRyder · « **Reply #1 on:** February 04, 2023, 04:11:28 pm »

Hi Bob, I am not familiar with the Wilesco parts. It is pretty easy to put a stiffer spring on a Jensen SV. The Jensen part has a 5/16-24 thread size.

I imagine the Wilsco SV would not be difficult to modify.

St Paul Steam · « **Reply #2 on:** February 04, 2023, 05:32:55 pm »

I just now checked out the S/V on my Wilesco D22 and it is pretty stiff, the shaft that goes through the spring is flared out on the end, you could grind that flare off & then try to re:flare that end, making the shaft shorter , thus putting more "crush on the spring & raising the threshold of PSI it would take to release the pressure of the boiler. that's all assuming you don't bugger the s/v while attempting all this. it would be better to make a new "adjustable" S/V.

Trainmaster · « **Reply #3 on:** February 17, 2023, 06:19:43 pm »

Wilesco has been quoted as saying their safety valve pops at 1.8 bar which would be 26 psi.

SteamerJ · « **Reply #4 on:** February 18, 2023, 05:32:06 am »

I would get some small stainless washers. Cut slots in them so they would slide over the shaft and slide it under the bottom of the spring. You could stack them to achieve the desired pressure. I have contemplated trying this with a Jensen one. I would like to do that and put an o-ring on it. I would love it if it didn’t leak. In my experience the Wilesco’s seal better.

komet163b · « **Reply #5 on:** February 18, 2023, 10:13:32 am »

Easey-peasey, piece-of-cake...

I take a short piece of copper pipe about the same diameter as the spring,
perhaps 3/16", slit it up the side and open it up enough to slip over the
S/V shaft. Hold the spring up, slip the slit tube between the spring bottom
and the retainer, close the tube, and you are done. Mine is about 3/16"
long and gets perhaps four more pounds of pressure. The longer the sleeve
the more the pressure. Just make sure you do not jam the S/V closed.

I added a photo of mine along with a video of my PM Research #7 running off
a Jensen #30 boiler. Pretty cool

Morning fun,
Wayne

SteamerJ · « **Reply #6 on:** February 18, 2023, 03:41:20 pm »

That works! We had the same general idea with a little different execution.

St Paul Steam · « **Reply #7 on:** February 18, 2023, 08:38:21 pm »

Since the stem is threaded , why not just put the correct replacement spring on and be done with it properly ?

SteamerJ · « **Reply #8 on:** February 19, 2023, 01:03:50 am »

Quote from: St Paul Steam on February 18, 2023, 08:38:21 pm

Since the stem is threaded , why not just put the correct replacement spring on and be done with it properly ?

I was looking at this on my phone and didn’t notice that it is an old one with a nut. A new spring would be the best option.

komet163b · « **Reply #9 on:** February 19, 2023, 09:15:45 am »

I have several Jensens with an S/V whose spring is
held on with a nut which seems to be unremovable.
Rather than force or ham-fist it, I opted for a
succinct answer.

Wayne

classixs · « **Reply #10 on:** February 19, 2023, 10:19:56 am »

Quote from: Trainmaster on February 17, 2023, 06:19:43 pm

Wilesco has been quoted as saying their safety valve pops at 1.8 bar which would be 26 psi.

I have not tested the current Wilesco safety valves, but would assume about 1.5 bar/22ish psi these days.

The 1.8 bar/26 psi number, origins from the original instruction sheets, accompanying engines carrying the earlier weighted safety valves:
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SteamerJ · « **Reply #11 on:** February 21, 2023, 10:57:58 am »

Wayne your #7 is nice. I got one a month or so ago. They run great but as most twins are steam hogs. I have mine connected to a Jensen 3” boiler. It’s great for just running it, but is totally inadequate if you want to do work with it. I can’t run the PMR generator very well with that boiler.

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Author Topic: Saftey Valve pop on Welsco, Jensen etc (Read 189 times)

Bobsmodels

Saftey Valve pop on Welsco, Jensen etc

RedRyder

Re: Saftey Valve pop on Welsco, Jensen etc

St Paul Steam

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Trainmaster

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SteamerJ

Re: Saftey Valve pop on Welsco, Jensen etc

komet163b

Re: Saftey Valve pop on Welsco, Jensen etc

SteamerJ

Re: Saftey Valve pop on Welsco, Jensen etc

St Paul Steam

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SteamerJ

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komet163b

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classixs

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SteamerJ

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