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031 Troubleshooting

Dana-Ridge wetblast machines are reliable commercial grade machines that are designed to work constantly and consistently day in and day out. They are not toys and we have customers that run them multiple shifts in a day and they cannot afford to have machinery down.

The pumps are extremely reliable and hard-wearing. Based on historical averages, approximately 12,500 to 14,000 operating hours from the urethane lined pump is achieved. **NOTE**Those figures assume the use of a larger aggressive aluminium oxide. Using gentler blast media, such as glass bead abrasive, achieves even longer life.  Glass bead is significantly softer and gentler. They are commercial machines designed to work long hours and we also keep a range of parts on hand.

In fact, most of the time that people think they have a problem with the machine, they immediately begin dismantling the pump believing it is the cause of the problem. Nine times out of ten it is actually something very simple.


Here we will look at some issues that may arise and the simple things that can be done to rectify it.

Water from the process gun but no Media

If when blasting you notice that it is taking a long time to process or is not processing at all even though water is coming out of the process gun you may have a blockage in your agitation. Our machines work when there is a good mixture of the slurry to water. This is achieved by splitting the flow between the process gun and the agitation nozzle

Not pumping efficiently

Check that the motor fan is turning in a clockwise direction when viewed from above. Also make sure it runs relatively freely when the pump is shut off ie. it doesn’t come to an immediate halt indicating binding.

Our machines are polarity sensitive which means they will not run as efficiently backwards as they do forwards. This can happen upon initial installation or during electrical work that affects all machinery plant-wide.

Some customers have happily used our machines for years before discovering they work even better going the right way.

A partially blocked filter. Cleaning the filter will ensure the most efficient flow of media.

Smaller machines have a fixed filter in the sump while larger machines have a cylindrical removable filter (pictured) behind the drain valve at the base of the pump

Overloaded with blast media – 

Open the drain valve at the bottom of the sump and remove excess amount.

Sump water level too low – 

Add more water simply by opening the filler valve until water begins to dribble out the overflow and then shut it off. 

Media coming out between the motor and the pump top housing and making a mess.

Clean out the machine overflow –

Over time, sediment can build up in the overflow, causing the water level rise in the sump AND in the pump. There are weep holes under the motor that are there to allow the media to escape if necessary. If they weren’t there, media would then be forced up into the motor bearing causing premature wear.

Do NOT fill the weep holes with silicone!

If the problem persists, make sure the flowback hose is also clear

Taking a long time to blast


  1. Make sure the media you use is the most appropriate for the task
  2. Replace worn media with fresh
  3. Use the media concentration jar regularly to ensure the levels are correct
  4. Add media if there isn’t enough

Worn nozzle or airjet in the process gun:

Check and replace as necessary

air compressor

Insufficient compressed air:

  1. Make sure the air compressor is working,  is connected properly and there are no obstructions (do not use nitto style fittings as these can restrict airflow).
  2. Make sure the compressor is rated correctly (multiple tools running off the same air supply must be factored in)

Not enough agitation:

Make sure machine is not overloaded with media.

If using very fine media and the machine has been sitting for some time then open the filler valve at the rear and start the pump. Once everything is flowing nicely then shut off the filler valve (MERCURY and COMET only).

 For MARS machines and higher:

Larger machines have an ‘anti-cavitation feature’ which means it will draw water from just below the waterline in the sump until everything is free flowing after which, it will draw from the bottom of the sump. If you find you are blasting with water only when you have confirmed the media level is correct then see below…

anti cavitation hose

Excessive Misting in the Cabinet

process gun
  1. Worn airjet in the gun
  2. Blocked vent in the roof of the machine causing cabinet pressurization

Excessive Water and Media Use

  1. Fill valve left on (causing good media to be washed out the overflow)
  2. Window wash set too high (again, causes loss of good media out the overflow)
  3. Excessive air pressure (Removes the water cushion and causes the media to break down faster)
  4. Some media are softer than others, For example, aluminium oxide will last much longer than crushed glass even though the finish they produce may be similar

Maintenance Schedule

Dana-Ridge wetblast units are efficient and tough. Like all good business practices, a little regular maintenance is what distinguishes a professional workshop from the others.

Still having issues? Please get in touch. At Dana-Ridge we pride ourselves on our commitment to customer  support and satisfaction. We also stock everything you need to keep operating into the future.

Get in touch with us today

Once you have one of these machines, you'll wonder how you ever got along without it!