# Silvia OPV adjustment old&new



## L&R

I have received two R-Silvias and started with usual mods with them. One is V2(fixed OPV), another V3(adjustable OPV)

This procedure is not something new but would be helpful to have a few more pictures in the forum.

Had to go down to 9 bar static to produce a decent shot, obviously these machine work better with lower brew pressure.

*Silvia V1,V2: *You need to buy some cooper washers for a car oil drip pan 16 or 18 mm, play with tightening the nut and combine different washers.

After some play I managed to lower pressure to 9 bar static, so old valves are adjustable too, but you need (1-2) extra shims.


----------



## L&R

*Silvia V3 and up*: We have an adjustable OPV inside so for it you will only need two 20mm wrenches. We loose the fixing nut that sits closer to the OPV and adjust brewing pressure with the other. Counter clock wise for decrease or clock wise to increase brewing pressure.









Gaggia Classic is far better in term of OPV adjustment and can produce high quality shots with higher static pressure 9,5-10 bar, but here more than 9 bar is to much.


----------



## Forestboy

Thank you for this, weekend project incoming.


----------



## L&R

Today I healed another one RS v1 with insane pressure. 12-13 bar it was producing really bad shots. Went down to 9 bar static and things are much better now.


Before 










After(one extra cooper shim has been added)


----------



## L&R

Another v2 on the right track, heating element upgraded(from Nancy) to bolt-in and pressure adjusted from 11 bar to 9.


----------



## dannoceti

Do you experience a big difference in shot quality after adjusting the silvia OPV from its stock setting? I've had mine for about 5 years and haven't touched the OPV. I have a V3.


----------



## 30621

Both my Silvias have the "non adjustable" OPV valves. I adjusted them by grinding the spring on my bench grinder. Take care with this method as only very small amounts of material removal are necessary. I went this route after adding a washer reduced the pressure too much. For example, one of my machines was set at 14bar and adding a copper washer reduced the static pressure to 8Bar; too low. To decrease the pressure, you can also remove the small calibration washer inside the OPV. This is the washer the factory installs to calibrate the OPV and it bears against the spring. I used the data supplied by ULKA to measure the return flow to the tank when a blind filter is installed into the portafilter. This is just as accurate as using a pressure gauge to determine static pressure. I set my machines to around 10Bar, which gives me around 9Bar brew pressure.


----------



## cap22

L&R said:


> I have received two R-Silvias and started with usual mods with them. One is V2(fixed OPV), another V3(adjustable OPV)
> 
> This procedure is not something new but would be helpful to have a few more pictures in the forum.
> 
> Had to go down to 9 bar static to produce a decent shot, obviously these machine work better with lower brew pressure.
> 
> *Silvia V1,V2: *You need to buy some cooper washers for a car oil drip pan 16 or 18 mm, play with tightening the nut and combine different washers.
> 
> After some play I managed to lower pressure to 9 bar static, so old valves are adjustable too, but you need (1-2) extra shims.
> 
> View attachment 24580
> 
> 
> View attachment 24581
> 
> 
> View attachment 24582
> 
> 
> View attachment 24583
> 
> 
> View attachment 24579


About to try to adjust my V2 OPV. A few questions for those who have been down this road: Do the washers have to be copper? Any tips on how to get the bolt on this non adjustable OPV to loosen?
Thanks for starting this thread a few years ago and providing the photos! so helpful.


----------

