Hi have had this rifle RWS DIANE 45 dated 07/86 for about a year now.

Have Stripped it to find a leather washer that looks undamaged and grey in colour,
it seals ok in to cylinder when it was out i soaked it in neatsfoot oil for about
half an hour and wiped of excess and refitted.

When using AirArms field diabolo 4.52mm pellets can only get 679-693 fps / 8.76-8.99flbs it seem quite consistant and disels slightly.

Any advise would b good

cheers

Bert,

Don't know if you are gonna like this info, but here's some data on two Diana 45's that I've owned:

Old style 45: 850 w/ cpls, 910 w/ lasers
New style (a commemorative model): 880 w/ cpls, 930 w/ lasers

HTH,

chasm

is that a RWS45?

looks more like a 35 . power level is more like a 35 too .

how is the breech seal? is it in good condition?

and the mainspring? was it bent or weak when you took it out?

how does it shoot with other pellets?

cleaned the bore?

Have claned the barrel no difference..
The Spring has a slight bend in it seems to b the original maybe?

Getting slightly better readings with diff pellet but nothing near 12 flbs.

The first couple shot dieseling well then settles down but still getting a little
white smoke.
It seems the leather washer is ok, need to replace mainspring and maybe a synthetic
top hat, the breech seal seems ok but will replace that too.

Is it norm for a leather washer to diesel slightly on each shot or will this go away like on modern nylon/ptfe washers?



Cheers

slight dieseling is normal after a lube job.

though the leather seal has been oil treated . i still might consider adding a couple of drops of compression chamber oil(one that's safe for leather seals), if you haven't already done so .
what i do is , drip some chamber oil in thru the transfer port hole , then point the gun upwards and roll it around so the oil will spread evenly along the compression chamber walls .

the reason i asked if it was a RWS45 was that even though the receiver may be marked as a model 45 , the wood stock looks different. more like a model 35 or 42 stock . makes me think that the gun may be assembled from different parts from different models .
just a theory , but you may have a different mainspring inside , either modified or one that's not from a standard 45 but from another compatible model?
some people swap to a weaker mainspring on purpose , trading power for better firing manners(less cocking effort,less recoil,ect.)

Could not find Chamber Oil in UK.
I have soaked it in neatsfoot oil.
Will that b ok?

I will source a mainspring and and fit.

I had to use a spring compressor as it was under a lot of tension.

The cocking effort on this rifle is more than my HW35K.

Would like to get this rifle back up to standard as i would like to use
for HFT as the recoiling class is more challenging.

Trigger takes some getting use to but the rifle shoulders really nice
and the squared forend feels nice.

Cheers

Yes your Neatsfoot oil will work. Mixed 1/2 and 1/2 with silicone oil would be better and RWS or Beeman chamber lube would be best. My seal was very dry and after soaking with chamber lube it is like new. Be sure and rid the seal of extra lube with soft paper towels.
Good luck
Chris