??????Anybody know the proper way??????

[Supertech87]

Does anybody know the proper way to check a reciprocating compressor for blowby, test procedures for suction valve and discharge valve any help appreciated.

[Grizzly]

Hi Supertech
There are a few post's on this subject.
Try using the search button and type in passing vales etc.etc.

Try the link below as an example!
Grizzly

http://www.refrigeration-engineer.co...valves+passing

[casstrig]

A good indicator of a leaky discharge valve is increased head temperature, compared to other head's it will be quite obvious also you can pump down not going into vacuum and observe the rate at which crankcase pressure increases and I like to use a clean screwdriver and place my ear to it your can hear a leaking valve very easily.Also whilst running if you have an elevated crankcase temp you have a leaky suction valve.

[coolhibby1875]

shut the service valve and if compressor runs and doesnt cut out on lp then its passing between valves

[NIKK38]

take the head off and have a look.....

[glenn1340]

take the head off and have a look.....

Bugger, now which cylinder has the leaky valve
http://images.google.co.uk/imgres?im...a%3DN%26um%3D1

[joe magee]

Front seat the suction valve. let it pump down. Close discharge valve. If the pressure starts to rise in the crankcase the service valves are not holding(yes I know the pressure will rise a little due to oil entrainment) If the crankcase is flat open the discharge valve and the suction shouldn't rise.

[D.D.KORANNE]

Yes, compressor can be tested for a leak back .Manufactured compressors are tested by developing an air pressure to 10 bar in a pressure vessel . Compressor is then stopped. A leak back instrument (usually with the manufacturer of compressors) measures air flow through discharge & suction reeds . And acceptance value is read on the analogue meter. This is fairly reliable method to assess leak back.