Ultrasonic cleaning

Mike Pass

I recently needed to clean up some carbs. I checked how much it would cost to get them ultrasonic cleaned. I found that I could buy an ultrasonic cleaning tank from Ebay for the same cost. So I bought a 6Litre tank, which had a big enough basket for the main carburettor bodies. I wanted to get the 20 litre one but there were none available at the time so went with the 6L. The tank is really more like 5 litres but it was still big enough for my items. The tank I got had the digital controls and cost about £100 delivered. One control sets the temperature and the other sets the time. I filled it up with water and 10% carb cleaning additive and set the water level so it was up to the line with the parts in the tank. It makes a buzzing sound when working and I set the temperature to 55 degrees.
The ultrasonic cleaning is done by transducers fixed to the underside of the tank, which send sound waves at 40,000Hz into the water. This causes tiny bubbles on the surface of the parts and the shock when these bubbles collapse is what cleans the parts. Because of this it cleans the internal passages as well. The carb additive smells a bit soapy and helps with oil and grease removal. Maybe dish wash soap would work as well. I gave the parts about 30 mins in total in 10 min bursts as it said do not run for more than 30 mins continuous. Small parts I put in a plastic box as they would fall through the mesh of the basket and parts should not rest on the tank bottom but remain in the basket. The tank gets hotter when the ultrasonic is on as energy is going into the tank. With the timer you can just set it and walk away. The heater heats up the tank to the temp set in about 5 mins. After ultrasonic cleaning I wash the parts under the tap and then blow out with compressed air to dry them out.
Does it work? Yes. It won’t remove very bad marking or corrosion but it gets parts clean. Really bad surfaces will need vapour blasting first to strip off the bad outer layers. The dirt removed is very fine. When I tried to filter the fluid to reuse it; it goes straight through anything you use to filter it. The tank has a drain tap so you can dump the old dirty fluid into the sink and flush the dirt out. I have since done a pair of 40 Dell’Ortos and a pair of 45 Dell’Ortos.
The usual before and after pic attached and one of the tank itself.


Tim Terry

I bought the 15L version for about $169 US and it worked beautifully for an Edelbrock carb rebuild - big enough to fit the entire carb body plus small parts. There are some good YouTube videos for ultrasonic tips and tricks.