Windmill weak air blast and suction

I am helping a friend of mine to fix her press. An old red ball windmill which doesn’t have the roller lock up function. The biggest issue is weak airblast and suction strength. We have open the air pump to clean the debris inside, but it doesn’t help much. Now the machine almost have no air blast and it needs to put on sucker caps to pick up some 300gsm cards. The air hoeses are new and properly connected. but the one connecting to the suction is having about 2mm larger diameter then the socket, which needs to be fastened with a metal ring.

Would this slight variation in air hose affect suction strength? Or are there other factors?

Any suggestion will be appreciated.

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H/berg, Blast and vacuum, Not facts just guesstimates transposed from, (fairly compatible) Thompson British auto platen!!!
The piston on the combined pump, incorporates large cast steel ring(s) which get gummed up with paper dust and frequently in times gone by, anti set off spray, which all accumulate in the ring grooves and eventually with heat and friction sieze the ring(s) in the groove(s) and cut down the blast/vaccum. But N.B. removal of the piston from the barrel is a very delicate job, especially for re introducing, snapped like the proverbial carrot!!! CAUTION??
On the base of the pump, if comparable to the Thompson, is situate a dump valve which is timed and adjustable and overlooked in cleaning.!!!

Fine gauze thimble filter on the suction pick up arm, cleaned/overlooked???

Piping to the pressure operated jogger/knock on delivery stack???

Paper dust, set off spray, built up in the multi-sucker pick up arm!! possibly where the open end of the bar connects to the flexi tubing from the rise and fall mechanism, heat and friction cook the system at the first oppotunity/bottleneck???

Hoses should ideally be, on the pressure side, *A* hydraulic style, or *B* plastic with Nylon laminate, in both cases to withstand, expansion and time lag when warm, resulting in pressure drop???

Vacuum side Hoses would normally be Rubber or Plastic but in either case, WOUND INTERNALLY with a coil spring to withstand partial collapse, when warm, under operating conditions. Vacuum and pressure, even at low levels but in volume always create a certain amount of heat???
My best GUESStimates, for starters** Good Luck.

check the valves on the pump should be slightly open unless you use the antiset off spray then you have 2 more valves below the feeder and delivery table that you can play around with close the one on the right side and open the one on the left side

also check that the air filters are clean if not use gasoline to clean them

If air blast is strong, but suction is weak, check that the hose, vacuum-trip and pump filters are clean (as stated above) and ensure the spring-metal clip on the sucker-bar is covering the hole used to reduce suction. Ensure that the sucker valves are open and clean.

The outside diameter of the sucker-bar can be increased to match the hose I.D. by using heat-shrink tubing found in the electrical section of the home-improvement stores.


Thanks everyone for providing many helpful tips. I cleaned the valves and changed the hoses. The machine now feed smoothly. Though I am still using gardening water hoses. It does heat up a bit during long runs.

Hi … I just had a problem with the air on our 2nd windmill . Little to no air blast, after cleaning ever thing and putting on new hoses, still not much air. I finally found the problem. Where the rubber air line joins the metal air tube there is a small air line that joins into that line. When manufactured the small line was attached and it almost blocked of the main tube, leaving only a small hole for the air to go. I was plugged up badly. Cleaned it out and it works well now.

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