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Ultrasonic carb cleaning

Pawl

CB750 Enthusiast
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Yellowknife, Northwest Territories, Canada
One of the first thing I did when I bought my CB last summer, after I bought it, was to have a look at the carbs. The bike had been sitting in a shed for 15 years, with a 1/2 full gas tank, the throttle would not even budge, so I kinda figured that the carbs must have been gunked up . .. . I was right. . . .that black gunk all over the inside of the carbs was hard as rock too!

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I have a friend who is an airplane mechanic, and he was praising the ultrasonic cleaning pretty hard, so I decided I would give it a try. He said to get one that has heating built in, so I did. I also searched for quite awhile for a deep one, 6"x6"x5.5", I bought from a company called Igem http://www.igem.com/ultrasonic-jewelry-cleaners.html The one that I bought doesn't appear to be there now (6" deep basket) as I write this? It cost $150 + $50 shipping (which sucks but a fact of life living this far north).

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The first time I used it I waited . . and waited . . and waited for the fluid to heat up, so the next time I just boiled the water first. Mine has a built in thermometer and the water was about 75 degrees C. I filled the tank about a little more than half way with boiling water, and a couple big glugs of white vinegar, a couple small glugs of Spray Nine, and a couple quick squirts of dish soap (all together, the tank is about 2/3 full).
I did the carb in 2 runs of 1/2 hr. each (built in timer), after stripping the carb down, the bowl and the body go in, after 1/2 hr. all the rest of the bits go in for another 1/2 hr. As soon as it comes out I throw it in some gasoline to get rid of any water. After drying off, I hit everything with a little bit of scotch brite (takes about 1/2 hr.) but any remaining grunge is very loose.

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This wiki link will explain how this really cool magic works. http://en.wikipedia.org/wiki/Ultrasonic_cleaning
If you can afford one of these machines .. . . Run out and get one!, you will not be dissapointed.
 

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Wow nice before and after shots! :thumbsup: I'm a fan of ultrasonic cleaning as well. I've been using a solution called Sharpertek 1220 degreaser/carb cleaner and it works really well. The Sharpertek really starts to work well once the heater gets the solution up to temperature. Here's a shot of my ultrasonic cleaner. It's a 5.5 gallon unit that I bought used on ebay. These aren't the best before and after pictures but it shows how clean it got these XS400 carb bodies.. Those were straight out of the ultrasonic with no polishing or scrubbing. Most don't come out so shiny and are more of a dull gray.

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I guess it might work if that was a Black & Decker Ultrasonic Sander?? . . . but somehow I don't think it is? . . . is there any before/after vid?
Ultrasonic cleaners work on a different principal . . . .than just vibrating the shit out of it with an orbital sander .. . . . but what the hell!!! . . why not give it a go! Wonder if it actually did any thing other than get the head wet?
 
My son is working on a set of heads for his Mustang. He showed me that video. I told him it was one of those too good to be true things. The real ones really do a wonderful job though. Wow!
 
Yeah no way that would work as well as an ultrasonic cleaner. I guess it's better than just dunking them in water, but you'd be better off using the carb dip you buy in a can for carburetors. There's got to be a better way to clean a cylinder head. Maybe with the right chemicals, the agitation provided by the sander would help a little bit, but I think your $35 would be spent better elsewhere. I really think the guy should remove the word ultrasonic from his video.
 
And this is what I need to do with my carbs as well. Diesel bath didn't work for sh*t..
 
This is all great information. I am just getting ready to tear into my carbs. At first I was not sure if this is something i should take on myself but I think I might give it a go. I am having a hard time finding a mechanic to work on my 74 cb750
 
Yeah most shops won't even touch them. I've heard of a local dealer that wanted $750 to clean a set of CB750 carbs. There was a small local shop, that is now closed, but they used to do them for about $275 and that was dropping the bike off with the carbs still on the bike. I had a friend that worked there and they figured 4 hours per bike. Anyway, with these older machines, you're better off digging in and learning how to do the work yourself. It's more fun that way anyway. If I get some time (yeah right!), maybe I'll do a write-up on cleaning CB750 carbs. :)
 
I probably do 2-3 dozen carbs per year, mostly twins , 350s 450s,etc and 750s. Here's our drill and hope it works for you.
Completely, and I mean down to the last o-ring and gasket, disassemble each carb, taking special car to remove all rubber parts.
Soak in Berryman's Chem Tool, 5 gallon "Pro" blend, the Berryman's you can buy at local dept stores in1 gallon buckets is a gentler and less effective mix. Check the MSDS sheets if you doubt me, the 5 gal stuff is much more toxic. Both are available on lone from Berryman's directly. Soak for 12-24 hours,depending on amount of varnish build up. If you skip this step you are asking for your ulatrsonic cleaner to work harder and you will needlessly burn through your expensive cleaning solutions.
Next drop your carb parts into your heated ultrasonic cleaner, use a Bransonic 8210 unit as it is large enough to clean a set of 750 Four carbs at one time. We use only Omega-sonics OmegaClean solution, diluted 10:1 per manufactures instructions. Carbs are soaked for 60 minutes and come out looking brand new.
I do not recommend using any acid based cleaners (vinegar, etc) as they tend to etch the aluminum and they come out grayish in color.
The Omegasonics is alkaline based and does not attack or etch the carb.
Carbs are rinsed thoroughly in a detergent bath, blown dry and then glass bead blasted if the polished finish is required.
All told its at least a 3-4 hour process so definitely not an inexpensive job, but the jets and passages are clean of all debris.
The cleaning solution is not cheap it runs aprox. $30/ gal not including shipping. We purchase it in 5 gal quantities and it is $160 total shipped cross country from CA to VT, we use almost 10 gals per year.
Many DIYers purchase poor quality USC (ultrasonic cleaners) from vendors like Harbor Fright and are disappointed with the results and then question the effectiveness of USCs ingeneral. My experience is that the better quality USCs are higher powered, offer heat as an option and swirl/mix the solution so that there are no dead spots in the cleaning process. Bottom line, ultrasonic cleaning is not the only way to clean carbs but when using quality USCs and cleaning solutions the results are unparalleled.
If any of you are interested in carb cleaning quotes, or pictures of our work please feel free to call me at 714-425-0360
Steve
 
sikopal,

dip and ultrasonics... that should do the trick! I knew of shop that used the dip with a basket that was on some kind of shaker to keep it moving. It worked well for them.

I also found that no solution in the ultrasonic cleaner works as well as the stuff designed for the job. The stuff I use is like $55 a gallon, but I think I use about 1/4 gallon per 5 gallons of water (what my unit holds). I'll have to look into the stuff you recommended.
 
Travis,
The Berryman's attacks the heavy surface contaminants and the ultrasonic gets the internals and jets, while cleaning up anything left behind. But the key to the two step process is that you don't burn thru your ultrasonic solution nearly as quickly as if you just throw the dirty carbs into the ultrasonic.
Omegasonics is a 10:1 ratio so I add 1/2 gal to my cleaner for each 5 gallon batch, works great!
 
I kind of feel like my ultrasonic cleaner might not be powerful enough, even though it was a $2,000 unit new. The ones with the external power boxes really seem to clean quickly! Have you ever done the tin foil test on yours?
 
Coincidentally just did one yesterday, because I was thinking the same thing (my unit seemed to be taking longer to clean). After 30 seconds the tin file looked like it had been shot by thousands of tiny bbs, lots of bumps and waves throughout the whole length of the sheet. I recently discussed how to get the optimal performance out of my unit with one of Branson's tech reps and he recommended keeping the cleaner fluid at operating level as indicated on tank and keeping the solution at high temp. He did mention as the units age (mine is 7 years old), if the cleaning liquid is run too low the transducers will eventually lose power and burn out.
He said to experiment with taking out a few ounces at a time to see the optimal level the solution needs to be at for best performance.
Mine seems to be about 3/4" below fluid mark. Again being an older machine it doesn't have all qthe bells and whistles of the newer machines like the swirl/mix that keep the US waves moving around the machine and prevent dead spots. I just shift my parts around for 2 cycles of 60 minutes instead of one in same spot.
 
Wow...very interesting info on this thread...I've gone through my carbs on my Cb750 times...but everytime I let it sit for couple of weeks it seems they need to be cleaned again,I'm guessing its the ethanol in gas these days... I was little apprehensive the first time I tore into them but now there's nothing to it...maybe I'll look into an ultrasonic cleaner
 
Damn ethanol! I'm glad the premium stuff around here doesn't have it so that's what I run in my motorcycles, boat, mower, and everything else except my car. It seems like the gas with ethanol goes bad much faster than the stuff without.
 
Very interesting, I keep a 5 gallon bucket of carb soak with its own dipping tray. It works well, but every 5-6 years I like to replace it.
Not sure if the cost of buying the 4 gallons I use of carb soak can be compaired to an ultrasonic cleaner for the cost. But as I do a bunch of carbs it may be worth the investment. I do wonder about surface corosion after sonic cleaning, not a problem with carb soak.
 
Very interesting, I keep a 5 gallon bucket of carb soak with its own dipping tray. It works well, but every 5-6 years I like to replace it.
Not sure if the cost of buying the 4 gallons I use of carb soak can be compaired to an ultrasonic cleaner for the cost. But as I do a bunch of carbs it may be worth the investment. I do wonder about surface corosion after sonic cleaning, not a problem with carb soak.
If you use the correct cleaning solution formulated for cleaning aluminum like OmegaClean you will have no problems with surface corrosion. Ultrasonic cleans by having transducers send a signal/waves through the cleaning solution causing cavitation which is like thusands of tiny air bubbles popping on the surface of the item, the popping is what releases the tension on the material and allows the contaminant to be released. No risk as long as you stay away from acids or alkalines in your cleaning solutions as they will attack the aluminum. Once you purchase a quality ultrasonic cleaner you will never go back to cleaning any other way, definitely worth the cost in my opinion if you work on carbs or small engine repair regularly.
 
Hi guys. I just bought semi-professional Ultrasonic cleaner and I am starting to learn with this. I am happy with the cleaning inside of carburators but the results of outside of carburators are not good, just check the pictures. I use 3,4 Gallons (13 Litres) Ultrasonic Cleaner, 40 Khz, 150 ºF (65 celsius), 20 minutes and tried 2 different cleaners - kitchen cleaner and motorengine cleaner (unfortunately I am still waiting for special cleaners designed for ultrasonic). What do you think? Thank you!

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That looks like corrosion on the aluminum, you will need to buff or glass bead that to remove it as the ultrasonic wont touch it to much. Try a wire or scotch bright pad on a hand held grinder. Even 600 grit sandpaper does wonders. Aluminum cleans up pretty good , it just hard to keep it that way after though. I guess some people spray a clear on for protection. I tried using Mr. Clean in my ultra sonic and worked pretty good, but you cant make it too strong in the water as then you could get discoloration to the aluminum.
 
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