Juwel 33 received and needs maintenance

Hello everyone, I've received a Juwel 33 stove that needs maintenance. Willing not to cause any damages as I've previously done to my juwel 34 (I assume so, when I found some damaged threads within the burner). I will start with giving it a bath of soap to be able to see and detect any problems in form. I will be more than welcoming your advices. Below is a first picture:

 

I would say a dunk test is your next step. Empty out any fuel. Close valve and fuel tank. Chill stove in the freezer for a few hours or overnight. Equalize pressure by opening, then closing fuel fill lid. Then submerge in a bucket of warm water, and see where the bubbles come out.

….Arch

 

Only needs to be left in freezer 15 minutes or so to get cold as the brass absorbs cold/heat quickly.
Duane

 

I guess I have a short attention span.

Mrs. Mac: “What’s this stove doing in the freezer?”

Me: “What? Oh, yeah…
Run me some hot water, ok?”

….Arch

 

Thank you @ArchMc and @hikerduane for these valuable advice.

Regards,
Migwar

 

Need kindly some help in dismantling the juwel 33 cap so to change the seal and pip, I don't know why I haven't found a link to that.

 

Looks pretty straight forward.
Duane

 

I used a screw driver, faced some resistance and the brass started to deform a bit. That is why I am asking not to cause any problems. Seems that I have to use some wd-40 just to losen the rusty cap a bit first.
Thanks again @hikerduane

 

Tapping all around, penetrating oil might help. Years of being in same position I'm sure. Grip the lower portion with well padded Vise Grip type wrench/plier, maybe a wide slotted screwdriver or long metal strip to allow better contact on the top.
Duane

 

Did a first dunk test. 15 minutes in the freezer then in transparent container with warm water. Line of bubbles was at the cap threads level. Changed the cap washer and pip, penetrating oil helped a lot, then did another dunk test, this time there was one bubble every 2 seconds getting out from the upper part of the cap, I believe this something related to the pip/spring functioning. I will replace the pip and test again (current pip is smaller by milliems in width).

 

Okay now cleaning the spindle and replacing the graphite around it, is there any diagram available, please?