Putting everything back together was like following Lego instructions. Thanks to all the photos and labels I had for everything, it was pretty easy to figure out how it all goes back together. Since the original insulation was missing, I replaced it with rock wool insulation (high temperature rated) that I bought in a roll off Amazon.



I triple-checked every connection to make sure everything was in the right place. Since the original tubing was nasty, I also put in some new silicone tubing.



Final shot of everything before leak testing. One thing I almost forgot - aluminum and copper don't mix! Copper can create a galvanic reaction with aluminum causing corrosion. I had to remove the foil from the insulation from any spot where it was in bare contact with copper.



Time to turn it on and bring everything up to pressure... as expected there were leaks...


Above: slow leak from the return line on the grouphead.


Above: leak from the pressure gauge.

Copper compression fittings are a bit of a hassle because there are two possible points of leaks at the connection (at the threads and at the joint). I had to re-tape a number of connections, test and re-test before the leaks stopped. I leak tested over 2 days to ensure everything is tight before I was confident in putting the casing back on.

After a few rounds of baking soda and Barkeeper's Friend, everything is cleaned up! Here it is after a week of active use at home.



What it looked like before:


I learned a lot about the workings of an E61 machine during this whole process. There are a number of things I would like to investigate further if I have time:

• The expansion valve is stuck.
• The float sensor is a bit twitchy. Sometimes after filling the reservoir, the machine won't turn on. I would have to reseat / jiggle the tank to have the sensor switch properly. One time during mid-brew, the float sensor tripped and stopped the pump and boiler. Luckily I was at 36g out and was able to salvage the shot with the residual pressure (it was like unplanned flow control).
• On the first day of active use, the steam boiler was set to 126C on the PID. After 45 to 60 minutes sitting idle, the steam boiler over-pressurized (past 2 bars) and was venting into the drip tray and it sounded like a steam kettle / small train. Turning the steam boiler down to 121C seems to avoid the issue. Could be an issue with the pressurestat in the steam boiler? Might have to slowly increase the setting and see if it happens again.

Thanks everyone for following along with this restoration.

GreenEggsAndSam wrote:Unfortunately, it looks like it is going to need to be replaced. There's a lot of mineral buildup around the seam between the gasket and the boiler, so it might be leaking at the moment. After descaling, you might reveal the gaps that the scale is currently sealing.

Yeah, I was afraid of this which is why I was only using very mild citric acid solution when descaling the boilers. The boiler is held together with the equivalent of duct tape and a prayer at this point. LOL So far no leaks from the boilers after regular usage and I will definitely keep an eye on it.

Possibly a stupid question, are boilers interchangeable with other vendors / models as long as they have similar specs and connections?

LOL So far no leaks from the boilers after regular usage and I will definitely keep an eye on it.

Hopefully it stays that way!

Possibly a stupid question, are boilers interchangeable with other vendors / models as long as they have similar specs and connections?

Technically yes, though you might be hard pressed to find one from someone that isn't a Quick Mill vendor.

That is an amazing job you did to restore that machine!
I wasnt planning to touch the exterior much on mine but seeing yours, I need to bust out my BKF.......

My E61 rebuild kit is coming in the mail today.... hopefully!

I found that baking soda paste does a great job at cleaning baked on coffee stains, and BKF makes a nice finish.

For deeper scratches I actually used Meguiar's car polish with a micro fibre cloth. While it wasn't able to remove some of the deeper scratches, it did minimize the more moderate scratches quite a bit. Just be careful to test a spot first and go light pressure as it does wear down the chrome finish.

Best of luck! Looking forward to your updates!