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Can any one tell me of a way to clean carbies prior to dismantling. I have tried a bath of thinners which did little to clean the bodies. Carbie cleaner & petrol. None work well.
Any suggestions would be welcome.
Jim
 

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I have used brake cleaner and towels, swabs, toothpicks etc.
It tends to be the strongest solvent I have around, and cleaning carbs seems to always need "more Power" ;-)

But I have not tried a lot of different things so this really isn't any definitive answer...

Cheers
Neil
 

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What you need is the carb soak cleaner that was available until ~ 20 years ago. Too effective to be environmentally safe nowadays. I wish I knew of a good replacement (hint, hint).. The only replacement I know if is elbow grease and mediocre solvents.
 

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Can any one tell me of a way to clean carbies prior to dismantling. I have tried a bath of thinners which did little to clean the bodies. Carbie cleaner & petrol. None work well.
Any suggestions would be welcome.
Jim
One interesting Idea I came acroos on the internet to clean carbs is to "Soda Blast" them with baking soda. After the blasting the carbs are rinsed in water and the Soda dissolves and is washed away. Dry with compressed air.

See at AircooledTech's Tools-On-The-Cheap - DIY Soda Blaster

FWIW

Ken
 

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Discussion Starter #8
Thank you all for your help.
Ken I like the soda blaster idea...it will be useful for many other applications.
Jim
 

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This is always the worst part of Weber restoration. This is a before and after of a pair I'm working on for an Australian customer. The steel parts that show are off at my gold cadmium plater, those and all the rest was all cleaned by hand. LOTS of tricks, and it does take some time. These were full of rust from a rusty fuel tank, but will be as new when they go back home.
 

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Discussion Starter #10
Hi Gordon,
Thanks for this, however how do you do it??? They look exceptional. Can you let me know how it's done?
Jim
 

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It's done by a complete disassembly followed by media blasting the castings after they have soaked at least 24 hours in a nasty solvent bath, the main ingredients being lacquer thinner and toluene. The best media is glass bead dust, collected from the vacuum dust catcher in a media cabinet. This dust at 60-70 psi does not imbed, and can be washed off with water. The passages are blasted with 175 - 200 psi air to clear them. If this does not work, the lead seals must be removed for manual rodding-out. Brass components are wire brush cleaned with the finest brush available followed by checking each jet with Weber jet plug gauges. It is all hand work.
The resulting finish is exactly as Weber finished the castings. On older versions, the magnesium in the alloy will quickly develop a darker color in small spots and blotches, just as they did when new. No acid or base cleaner can replicate the original factory finish. It's taken me about 40 years to perfect this restoration technique, done carefully, most, (not all) aged or abused DCOE series Webers can be restored to original factory appearance and function.
The solvents are nasty, and the media work takes practice. My Alfa business is purpose built street and racing oil pumps, but I also do Weber restoration when I have time.
Here is a before and after of very early 40DCOE2 large top Weber restoration. These are both numbered in the low 500's.
This work is not inexpensive as it is time consuming, but still generally cheaper than new Italian replacements.
 

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Discussion Starter #12
Gordon,
Thank you very much sharing your experience. I have just built my own cabinet for this purpose and will start using your methods as this is the best work I have seen anywhere.
Again Thanks
Jim
 

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Gordon,

I notice that there are brass shafts in the last photos. Several comments here are that these sometimes twist from the internal and external springs. Do you replace these with the newer steel shafts while they are apart? Mine are also brass, but work fine so I've no plan to replace them (and have no plan to disassemble them again!).

The butterfly screws (at least in the carbs with brass shafts) are staked to lock them to the shaft; removing them can cause some deformation of the threads (and takes a lot of care and a perfectly fitted screwdriver). I've re-installed them using locktite red and re-staked them, and have not had any sucked into the engine. At least not yet!

The hardest part is cleaning all the passages as you said. It takes a lot of skill and experience. I know some people that have badly damaged the jets using drills and wire to clean them. Your reputation of doing this is correctly well earned.

Robert
 

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Gordon,

I notice that there are brass shafts in the last photos. Several comments here are that these sometimes twist from the internal and external springs. Do you replace these with the newer steel shafts while they are apart? Mine are also brass, but work fine so I've no plan to replace them (and have no plan to disassemble them again!).

The butterfly screws (at least in the carbs with brass shafts) are staked to lock them to the shaft; removing them can cause some deformation of the threads (and takes a lot of care and a perfectly fitted screwdriver). I've re-installed them using locktite red and re-staked them, and have not had any sucked into the engine. At least not yet!

The hardest part is cleaning all the passages as you said. It takes a lot of skill and experience. I know some people that have badly damaged the jets using drills and wire to clean them. Your reputation of doing this is correctly well earned.

Robert
Hi Robert,
As usual there are some weber tricks involved. The brass shafts can be replaced if twisted, but the more common need for replacement is wear in the center bushings from the spring pressure. Sometimes a slight twist can be corrected, but with wear and a bow in the center you get uneven idle no matter what you do.

The butterfly screws are interesting. The early brass ones can be "unstaked", removed and re-used, (sometimes). The new steel ones I grind off the staked area and use new ones. The new ones are glued in with either Loctite Red, or number 290 Green, depending on the situation. I do not stake these, as they never come out. BTW should a brass one get into an engine, it does MUCH less damage than the steel ones!:)eek:)

I have a set of Weber jet drills (vey tiny and very fragile!) and a set of plug gauges. These are not used as you would suspect. I recently had a #65 starter jet plugged hopelessly. A # 60 Weber drill was used in my fingers to get a hole through the plug. Then a #60, #62 and #64 plug gauge was used to clear the remainder of the plug using lacquer thinner as a lubricant and cleaner. Finally it was blown out with Brakeclean and air and checked with the #64 gauge that should pass freely. The #65 would be used to check for any OVERSIZE jets. The correct # gauge is a TIGHT fit in the jet. NO wire or drills in the jet orifice unless undersize.

Body passages that are hopelessly plugged must be cleaned the "hard-way". I remove the lead plug and manually clean them out with regular twist drills, either hand held, or using a pin vice. Once cleaned, I can either re-plug with lead, or I prefer to tap the end of the gallery and plug it with stainless steel (hard) little metric allen screws held in with Loctite Blue. This allows for future removal and clean out with less hassle.

I have no secrets, as I've learned this over MANY years. If I share my experiences, others will benefit.:cool:

I hope this helps!
 

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Some other examples, both from Keith Goring. The first three pictures are a set he sent me as the dirtiest Webers he had seen. Not a cheap job, but they came out new. The fourth picture is an "after" picture of a early pair of 40DCOE2 race Webers. They had been externally polished shiny, like chrome!!! Now they look the way they should. This took three different grades of media.
 

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I've been able to keep the passages clean in use. One way I manage this is to drain the carbs with a syringe when they are gonna be idle, then fill with lacquer thinner. It's amazing how much crud will come out if you're willing to let them soak for a week or three; as always, rinse, repeat (several times). I have a box of various jets, so when I get one really fouled I just replace it. Same for the idle adjust screws.

I have used glass beads on the castings too. I got a workbench blast cabinet at Harbor Freight for $99 on sale. I always use a lot of masking tape, and blast before disassembling to minimize the beads and dust that gets inside the carbs; you do have to be very careful cleaning them afterwards to get all the fine stuff out. I've also used big (6 to 8 inches) very fine wire brushes to clean the outer castings - you get a shinier finish, but it softens soon enough, and can be softened with some spray-on chrome wheel cleaner too. Oven cleaner and paint stripper are sometimes needed too. I got two boxes of XL disposable nitrile gloves at a tool show a while back to keep me from dissolving.

The hardest passages I've found to get/keep clean is the accel passages (because of the screw-in backflow valve) and any others under the few little steel balls.

You've renewed some really bad carbs. I've been luckier. But I don't get paid either.....

;)

Robert
 

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I believe I may have dissolved myself. The solvent thing is something best done right before shop evacuation, or outside. ALWAYS far from open flame or any source of ignition. That is, without a doubt, the worst part of Weber restoration.
 

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My college roommate - way back when - was an organic chem major. He hated gloves and the lab hoods. By the time he graduated he'd dissolved his mucosa and couldn't smell anything. probably had severe liver damage too, or else he was a student AA.
;o

Robert
 

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I'm working on a set of DCOE24's that aren't too bad. Most of the crud is coming off easily with Gumout. Soaking stuff and patience are paying off. I noticed that the acceleration pumps are at different heights, so one is travelling less when opening the throttle. I opened the cover to see the center of the shaft and don't see anything that looks unusual. The levers look okay, not bent or anything, one just doesn't move as far as the other. I guess it's at a different place on the shaft, but it's pinned in place. Is this likely a problem? Is there an easy fix? I'm reluctant to disassemble the shaft unless I have to. The throttles seem fine and fully close and open. Thoughts?
 

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Different length pump rods used to be available. I believe three lengths. Now here in the USA we only get the LONG rod. All is not lost as these can be cut to the shorter lengths as required.
Check the "PUMP-STROKE" for your particular application. As the Weber was designed for a multitude of applications, my guess is you have two different length pump rods. Pull both pump assemblies and compare.
 
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