caravel2

ARRAREX VAM/CARAVEL

piston seals replacement

The VAM and Caravel are machines with a low maintenance, limited to replacement of the seals of the piston.

	The piston is composed of three parts:
	- the head for attaching the piston to the boiler		the head is fixed on the boiler on early models with a ring and a mechanism that rotates and blocks the head on the boiler. The ring disappears in later models that use a removable pin.
	- the hub		the hub on the first model is spherical, then flat and finally protected by a sleeve
	- the body with seals		the piston body in the first model uses two identical sealing lip, in the second model the top seal is replaced with an o-ring. in the last model the seals are replaced with the adoption of two internal o-ring. On all models (except VAM) there is a small o-ring inside.

Types of piston



first model with hub spherical (VAM)	second model with hub flat

third model with hub and sleeve	fourth model with top seal o-ring

fifth model without seals (inside piston housing)

The seals

The original seals, of course, are no longer available so the only solution is to find seals compatible.

After several researches carried out at local stores and some testing done with a test machine, I found lip seals that fit perfectly.

No problem for the O-ring seals that I found identical to the originals.

	Original seals		Suitable seals
piston seals first models (couple) and fourth model (single)		inside = 28 mm outside = 37,5 mm height = 6 mm		inside = 27 mm outside = 37,5 mm height = 6,5 mm
top seal piston fourth model		inside = 35 mm depth = 2 mm		inside = 35 mm depth = 2 mm
pistone seal fifth model (inside the boiler)		inside = 36 mm depth = 2,6 mm		inside = 36,17 mm depth = 2,62 mm
bottom piston seal		inside = 4 mm depth = 2 mm		inside = 4 mm depth = 2 mm

Seals replacement

To proceed with the replacement of the 3 seals, must dismount the body of the piston, removing the ring that secures it to articulated shaft

Then remove the small o-ring seal on the bottom of the piston with tweezers

remove the other two seals and clean the piston from the residues of fat or limestone

insert the new gasket and refit the shaft

before reinserting the piston into the boiler lubricate the seals with silicone-based grease for food contact.