A Lotus buddy recently purchased Harbor Freight's (USA) 2.5 liter ultrasonic cleaner or doing small car parts. US$74.99. Yesterday he bought a second one with a 20% off coupon from an add he received in the mail... US$60.
http://www.harborfreight.com/25-liter-u ... 95563.htmlTank Internal Dimensions:
3? D x 9-3/4? L x 5-1/2? W
Outside Dimensions:
11-3/8" L x 9" W x 7-1/4" H
The instructions suggest a water & detergent solution, but we're going more heavy duty for engine parts. The water-based solvent from his large tank-style parts washer works great, but GUNK parts cleaner, the soaking type of carb cleaner, or similar low-volatility solvents should work equally well. Whatever solvent you swear by for soaking parts clean will work more effectively with an ultrasonic assist. I wouldn't use any highly volatile, flammable solvents as they will evaporate even more readily with ultrasonic energy... greater risk of a flash explosion and fire if the fumes find a spark.
We've been using it to clean hardware and small parts, up to the large goose neck thermostat housing from a Esprit 910 engine. That piece could lay down in the tank, but part of it stuck up out of the bath, requiring us to rotate it and repeat the timed cycle.
One thing I don't like about the Harbor Freight unit is that it has a timer with a limited range... 4.88 minutes as I recall. You can quickly re-set it for another go, but you can't just turn it on and leave it over night. Hmmm... maybe I can cobble up a power over-ride switch...
It does a very good job on general dirt and greasy grime. Wipe excess loose dirt and grime off engine parts with a paper shop towel, but don't make any special effort to pre-clean them. One timed session in the tank makes a very significant improvement, while two pretty much have them clean.
It made progress on water lime scale on the thermostat housing, but was slow (~1/3 gone in 20 minutes), so we moved on to a wire wheel. That would be a good job for the power over-ride switch.
So far it has not been effective against cured Loctite in threads... that still requires a wire brush or chasing the threads with a tap/die.
It will not clean up or polish corroded parts... they will be clean but still corroded. For those, a vibratory polisher (Eastwood) or rock polishing tumbler (hobby shop) works well to brighten them up... better yet, just replace them.
I've been eyeballing it, thinking that it just might take a stripped down DHLA or DCOE carb body laying with the throats horizont. A DCOE is by 7.24 wide across shaft ends by 4.65" from mounting flange to inlet without studs (5.43" with studs), so it should drop into the tank with the throats horizontal. However it's taller to the top of the float bowl than the tanks 3" depth, so fully cleaning may require flipping it over and repeating... however long it took. Jets and small parts should fit in the tank at the same time. My carbs are all on engines, so I haven't tried it yet. Varnish deposits are hard, like the lime-scale on the thermostat housing. The last time I had a badly varnished-up DCOE professionally cleaned, they had to soak the body in an ultrasonic cleaner for a solid week to get it clean.
To our experience, the Harbor Freight ultrasonic cleaner works well on hardware and small parts in a relatively short time without any human effort.
Regards,
Tim Engel
Lotus Owners Oftha North (LOON)