Vacuum Pumps - Types & Maintenance
Blackmore Turbo/Needle/Gear seeders are provided with vacuum pumps and air compressors manufactured by GAST or Thomas.  When requesting parts, please provide the make and model number of your unit. The seeder manual has diagrams and parts lists of all the pumps, or pamphlets are included with the machine.

A GAST pump service kit is available and includes new felt filters, carbon vanes and gaskets. A seeder maintenance video which includes vacuum pump maintenance and repairs may be ordered.

Pumps provided with the machine are primarily from GAST. These are of a bluish/gray color. Pumps that are blue, are made by Thomas. Please provide pump manufacturer and model number of pump when ordering parts. For example, GAST 0822.

Pump Model                Service Kit
0522 GAST                  K247
0523                            K478
0822                            K223
0823                            K479
GAST Model #0823 PDF
Blow Them Clean (top)
It is a good idea to blow off the cooling fans and fins on the motor part of the vacuum pump with compressed air. It is surprising how much dust accumulates on these parts that are essential to proper cooling of the unit. The vacuum pump motor is made to run hot (often you can’t place your hand on it) and has a thermal over-load to prevent it from overheating, but anything that helps the unit run cooler will also increase its service life.
Seldom does the pump itself fail (8000 hour service interval) but motors running near their thermal limit can be more problematic. While you’re at it, do the same thing to the cooling fans and fins on the air compressor that provides the high pressure blow-off air.
Clean or replace the filters as necessary.
Call Blackmore with any questions.
High Pressure Pump – Droop the loop (service kit – K309) (top)
Condensate normally accumulates in the air hose connected to the high-pressure 2-way solenoid valve as air is compressed and water “squeezed out”. New seeders or those that have been updated at the factory have a water separator installed prior to the valve. It prevents the condensate from entering the valve and seed pick up manifold. It is easily installed if your machine does not have one.
There is another place where this condensate shouldn’t go; the head of the high pressure pump. As long as the pump is on, the water in the hose won’t drain back into the pump. However, when the pump is turned off, this moisture will drain into the head of the pump (the small one) unless the hose droops several inches beneath the pump.

Drooping the hose loop ensures that any moisture in the line drains to that low spot rather than into the pump when the pump is shut off. This is particularly true at the end of the day. Corrosion in the pump makes the reed valves stick so no high pressure cleaning air is delivered to the manifold tips.
See the next section on checking high pressure cleaning – check procedure.

Contact Blackmore with any questions, to order a water separator or a MOA pump service kit (K309)
Vacuum Pump – Flushing Procedure (top)
Store the vacuum pump in a clean,
dry location to prevent corrosion.
The vacuum pump is largely maintenance-free. Keeping the filters clean will ensure optimal operation. The pump is designed to run hot, thus during normal operation, it should not be touched. A thermal overload will shut it off automatically should it become too hot. Place it near the floor where the temperature is cooler, but keep away from excessive dirt. To prevent hoses from blowing off, it may be necessary to hold them on with a twist tie or some type of clamp. A clothes pin works as well.
The vacuum pump is never to be lubricated but filters should be checked and cleaned every 100 hours of operation or less. While filters are removed for cleaning, or periodically, the pump should be flushed with an oil-less, nonflammable solvent. This is available from Blackmore or use brake cleaner in an aerosol can that may be purchased at your local automotive parts store. At the very least, flush the pump before storage at the end of the sowing season. The rotary vane oil-less vacuum pumps are rated at 8000 hours service interval. They usually cause problems only after being shut down for the off-season without being flushed out.

To flush the pump...

  1. Remove filters and hoses.
  2. In a well ventilated area and wearing eye protection, start pump and into the vacuum orifice direct a two or three second long spray of flushing solvent. The black carbon dust will be blown out the other side;
  3. Repeat two or three times.
  4. Reinstall filters.
  5. Allow pump to run for several minutes and then reconnect it to the seeder.
  6. Check that you have good vacuum and blow-off pressure.
    * If it is necessary to remove or replace the carbon vanes in a pump, when removing old vanes note which side the bevel is facing so that the new vanes may be similarly installed. If the old vanes are stuck in their slots, it may be necessary to break them out. Use the end of a flat file and tap gently with a hammer. If they are not broken or too badly worn run a fine file over the flat surface before placing them back in the slots. If, after filing, they still do not slide freely in the slots, they must be replaced.
  7. Flush all debris out of the pump before reassembly.