was wonder is layering the new silicone gasket on top of the old one was a good idea?
The white ones are much softer and thiner.

The gaskets should be about 2.5mm (I use 3/32" material).

The gauge you received is for use with flared tubing, not the bullet-nose fittings used on Marzoccos.

Bloody hell! That's just wonderful. I mean the new gauge fits and I can tighten it, but I can guarantee that there will be leaks or issues once operational.

Thanks for you PM Barry.

update:

so I learnt a thing or two yesterday...Always plug used equipment before purchase or prior to rebuild.
I was obviously excited when I got the machine and didn't bother plugging it before taking it apart. I was optimistic as always.

So here is a little recap.

I don't have a motor and pump yet, so I connected the machine directly to the cold water from the washer. and started to fill it slowly. The pressure was at 3 bars according to the gauge.

There were less leaks then I expected:

tiny leaks from the end caps of both brew boilers.
leaks from the pressure release on top of group head 1 and 4. This might be a case of changing the brass washer?
leaks around the drain cup expansion valve. my mistake, as I didn't put the spring properly inside the valve tube.
small leak from water inlet manifold.

The sigh glass filled up till about 1/3.

Because there was a loose wire on the relay, none of the heating elements were heating. After tightening the wire, I noticed that only the steam boiler was getting hot.
Any idea why the brew boilers weren't warming up? perhaps not filled up enough or didn't give it time to heat up?

The most disappointing part is that one cronos pads didn't light up!
the other 3 had blinking LED lights and a count up to 90 or 120, can't remember and i have no clue what that means??

No steam came from the steam wand. Could this be because there wasn't enough pressure built up?

The hot water button didn't dispense any water either.

Not sure how much of these things had to do with not having a pump/motor....

as always, any input is appreciated guys. I'm feeling a bit lost.

tiny leaks from the end caps of both brew boilers.

should be none.

leaks from the pressure release on top of group head 1 and 4. This might be a case of changing the brass washer?

Those screws need to be loosened slightly until the air is vented from the brew boilers, then tightened down. If they leak, then yes, replace the copper washer.

Because there was a loose wire on the relay, none of the heating elements were heating. After tightening the wire, I noticed that only the steam boiler was getting hot.
Any idea why the brew boilers weren't warming up? perhaps not filled up enough or didn't give it time to heat up?

No steam came from the steam wand. Could this be because there wasn't enough pressure built up?

The hot water button didn't dispense any water either.

Hot water dispensing requires the steam boiler to be pressurized.

No steam generally means no pressure (unless the wand/valve/line is plugged up somewhere). Did any pressure register on the gauge?

Did anything come out of the steam wand when you opened the valve? Air, perhaps?

I don't think I gave the steam boiler enough of a chance to fill up or to get hot.
Only pressure on the bottom half of gauge was up, to about 3 bars. zero for pressure.

Nothing came out of the steam wand. no air, no water, no steam.

It's so scary to light it up for the first time. It's as if it might explode immediately if something is wrong.

Yeah , I was expecting water everywhere and sparks to fly...but it went alright. Few leaks.

So I finally received a new Procon pump (160$) and a new 1/4HP Dayton motor (50$)

I would appreciate instructions on how to plug it all up now. What I would like is to connect the pump to a 5 gallon water bottle, to safely run tests. Is that possible?
Should I be adjusting anything (motor or pump?)
Is there a sequence to follow?

Do I need to by pass anything? Came across a post about a pump or motor constantly running and having a negative impact on the machine....

You have to have water in the pump at all times. So you will need to "prime" it by funnelling some water into the tube. Then when the pump starts you have to dunk the hole into the bucket. For the most part it will probably suck out of the bucket. But keep in mind that it will suck a lot of water initially and you don't want to run dry.

If the machine is always running it could be a problem. But I think it's mostly if the steam boiler is filling when you are taking a shot. I guess it might reduce pressure (especially for you) but also for HX machines (not yours) it would cool the boilers temperature and that might affect the temperature of your brew water.

I don't know about your pump, but you might have to adjust it to bring it up/down to the 10 bars of pressure. Unless you bought it configured for 10 bar?