I finally managed to get the Achilles working again.
It wasn't easy though primarily because of my lack of knowledge.
My initial problem was air leakage from the Air inlet port on the air reservoir side.
My observations are as follows
1) when I opened up the Air reservoir I found a small seal that compresses and allows the air inside and also prevents the air leak to be damaged.
2) There was gryme around it. As I use a hand air pump (Chinese made) to fill up the reservoir, gryme had got in. On further checking the Air pump itself I found that I hadn't installed the filter that came with it. Hence gryme had got in. So it wasn't the Chinese made pump but my ignorance
3) Now my air rifle itself had been dismantled for more than 6 months as I was searching for cheaper alternative to source the small seal. Which I found was almost impossible and I ended ordering entire seal kit from precihole.
4) Now after replacing the small seal there was leakage from the side where reservoir attaches to the trigger assembly. Took some time to figure out the problem as it was another damged small seal on the pin that allows the burst of air to come out when the trigger is pulled.
I was able to find the small rupture on the seal only when I used a lens.
5) After replacing that there was leakage from the reservoir and connector threads towards the trigger assembly end. Which I replaced.
6) What i realised was that due the reason that I had dismantled the rifle and was exposed to air for more than 6 months the seals had hardened. Also these seals tend to wear out soon, as they withstand such high pressures.
So ordering the entire kit seemed worthwhile.
7) Finally I assembled it back with little bit of Teflon tape and silcon grease on the seaks.
(I was thinking of using loctite Sealent for threads but opted for Teflon tape)
And finally I have my Achilles back in working condition.
Thanks to primarily GNV and few others i got it back working.
Few pictures of the seals that I replaced for your reference.
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