Why is it the small jobs always end up being difficult.

Decided to change the seals.

All pretty straight forward but getting the brass seating ring off the piston was a nightmare. Especially when the piston is made of cheese.

Managed to gouge a few pieces out of the piston but luckily didnt effect the seating of the new Diaphram .

My brass ring also has an O ring in the middle which others dont, Although that seal was broken I managed to reuse it as I didnt have a replacement.

Overtightened the bolt holding the compressor to the EAS box and sheared it off.

Luckily its working nicely despite the problems.

Isn't the O ring you mention just the remains of the old seal?!

The brass seating ring is grooved for the O ring to sit in. Others Ive seen are just solid brass rings without an O ring.
The kit comes with 1 tiny and 1 large O ring for the top chamber and a plastic type Diaphram for the piston, no other o ring for the brass seating ring.

How hot can these things get.

Just checked it after being parked up for 45 mins and its too hot to touch.

It sounded fine to begin with but now sounds like its about to go bang, though it is only held down with 2 bolts at the mo so that isnt helping.

Until the thermal switch cries enough, I suppose! You could push the boundaries of science and read the temperature up to the point where it either

1. melts
2. the cutout cuts in

They do get pretty hot - especially if they are working hard...

The thermal switch is set to cut the compressor out at 120 degrees C - which is in the 'too hot to touch' category for me!

riddlemethis wrote:

The brass seating ring is grooved for the O ring to sit in. Others Ive seen are just solid brass rings without an O ring.
The kit comes with 1 tiny and 1 large O ring for the top chamber and a plastic type Diaphram for the piston, no other o ring for the brass seating ring.

Hi I found that my piston had an o ring and a ruined diaphragm and after looking at the Paul P38a website my block has different holes in it as well

riddlemethis wrote:

The brass seating ring is grooved for the O ring to sit in. Others Ive seen are just solid brass rings without an O ring.
The kit comes with 1 tiny and 1 large O ring for the top chamber and a plastic type Diaphram for the piston, no other o ring for the brass seating ring.

Hi I found that my piston had an o ring and a ruined diaphragm and after looking at the Paul P38a website my block has different holes in it as well. I didn't fit a new o ring even though I have some as I thought it must have been a bodge, apparently not. But the piston is working fine now haha

I have done three now, all have had the grooved seal retainer with an O-ring that keeps the seal from moving inwards.

All have had 125 Deg C switches, I see an ebay vendor in Europe selling 100 Deg C switches, you pays your money....

I've bought some Airpax 125 Deg C switches in from the USA.

Peter

I've refurbed 5-6 and never come across an original under the brass ring. At least if I do another and find an o ring I know it's not a bodge, thanks guys