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Sun May 22, 2016 7:50 pm

I did a soap test and found two leaks on the propane regulator. I also found that even when the valve to the regulator was closed the whole below would leak.. time to replace the regulator and valve but two questions
1) the white cap the covers a screw that has vent written above it, what does that do
2) is there a case when there is supposed to be a leak at the red arrow on the right hand side?

Leaks at both red arrows

Sun May 22, 2016 8:02 pm

Those look like pinhole leaks.
And, if it's a square or rectangular shaped regulator, which it appears to be,
It's likely the original part which IMO should be replaced regardless.
If I'm not mistaken the old style reg is a one stage the newer Marshall is
a 2 stage.

Just my .02 or 11 WC. ;)

Neil

Sun May 22, 2016 8:36 pm

Thanks Vanagon Nut!

It is the rectangular one, but it is a two stage. It says "Model 200 two stage LP gas regulator" and is a marshall

Glad too hear that it should be replaced anyway. I don't like replacing things that aren't the original unless they really need to be.

By pin hole leak do you mean something punctured it? So there isn't supposed to be a hole there? I am pretty baffled how a pin hole leak formed there since there has been a plastic cover on it.

Sun May 22, 2016 9:07 pm

I don't the process behind this but if the LP expands within
the reg, would this produce moisture, or more moisture, and leave some behind? WAG on my part but my gut tells me that moisture is a part of the process. There's certainly moisture in the fuel.

Or, moisture inside tank is getting into the reg?

I dunno. I'm stepping out of this thread in 5, 4, 3, 2.... ;)

Neil.

Mon May 23, 2016 12:07 am

All of those original regulators should have been replaced by now, they had a super-high failure rate and Marshall replaced them for free until stock ran out. Replace with the latest model and no more worries.

Mon May 23, 2016 8:29 am

The old style Marshall round diaphragmed regulators are much more robust than the newest square / rectangular replacement regulators that are available today.

The origina 30 year oldl regulators are just being replaced, the square / rectangular units don't last 1/4 as long.

Mon May 23, 2016 9:12 am

Regulators have some venting, take (saw?) the old one apart and you'll see a rubber diaphragm - looks kind of like the inside of a fuel pump - works against a spring with gas pressure on one side and atmosphere on the other. So there is a vent to give an atmospheric pressure reference to the diaphragm. Maybe a couple more holes to let moisture drain, often a regulator runs cold due to the expansion of the gas inside and this can lead to condensation internally. If outdoors in freezing weather this can have bad consequences.
If the holes are nice and round, they are meant to be there, if jagged then there has been some corrosion!
LP gas regulators are made of an aluminum alloy, not particularly resistant to corrosion. Compare this to the regulators on top of your welding cylinders, made of red brass because you want them to last.
But of course they co$t a lot more.

Mon May 23, 2016 4:21 pm

Yeah, I think the diaphragm failed on this one since it is leaking out that hole on the right side of my picture. The hole certainly looks like its supposed to be there.

I have a regulator on the way from van-cafe and a valve coming from some random company. They claim it is a 9106CO and only $20. That would be saawwweeeeeet

At some point I am going to look into seeing if there is a 3 way t that can be put after the regulator. The third nipple I'd use for hooking up a 5 lb or smaller propane tank with regulator.

Wed May 25, 2016 8:48 am

Yesterday I manage to drop the tank and replace the service valve (shut off) and regulator. It was really easy. Well... removing the service valve from the tank was a bitch but with a good dead blow hammer and decent sized crescent wrench I managed.

The guy at the propane shop said I didn't need the service valve with the relief valve because I already had the fill port but I have one on the way anyway.

I ordered the Van Cafe regulator and needed to bend the copper pipes. One is pretty close to hitting the bump guard on the bottom. I want to cut the pipes for a better fit but I will be installing a three way splitter later. Anyone know if the regulator will be protected from back pressure?

A couple tips
1) remove the propane splitter after the regulator and the job is much easier.
2) Inside the kitchen cabinet there is a metal bracket that holds the two copper pipes to the wall. Loosen this screw so you can push the copper pipes up into the cabinet.