Topic: Carburetor disassembly

[MotoRico]

Is there a way to soften the insulating boots while they are attached to the carbs and intake manifolds?  I have a set of carbs with the manifolds but the rubber is stiff and unyielding.

Any recommendations on something I can dip the entire mass into to clean and facilitate disassembly?

In the tech tips forum there is mention of Simple Green for cleaning the carbs.  Is it safe for the rubber parts?

[dusterdude]

blowdryer

[flatblack]

Yeah, blowdryer or heat gun to get the boots off the carbs.  DOT3 brake fluid is supposed to do a good job at softening hardened rubber parts, over time.  Never tried it, but others swear by it.  Obviously, the boots should be separated form the carb rack before they are soaked in brake fluid.

I wouldn't use Simple Green.  It's known to be corrosive to aluminum.  If you must, use Simple Green Extreme, or at least flush it really well.

That's why stuff like carb dip was invented.  Once the boots are off, break down the rack into individual carb bodies, bowls and jets, then throw them all in the carb dip (gallon bucket at most auto supply stores). Get some aerosol carb/choke cleaner and use compressed air to blow out the crap.

HTH...

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[Dave L]

Hi
Well the best way ive found on the 550f2 i had was to push the boots back into the air box up to the last bit ,this gave just enough room to withdraw the carbs out the kickstart side.

On reassembly i refitted the carbs back onto the engine rubbers with the aid of a bit of grease, then after soaking the intake boots in very hot water offer up the top edge to the carb and with some wire flex through the lower front part pull it on to the carb the by hand and with a non sharp tool work the back onto and into the
air box ,its a real pain worse than working on the caarbs themselves its very hard work indeed but after five times it does get a bit better .
good luck

DAVE

[.RJ]

I wouldn't use Simple Green.  It's known to be corrosive to aluminum. 

The carbs are more pot metal than aluminum - I've used simple green to clean/soak a lot of carb (and other alum) parts here and there.  Dilute it 50/50 with hot water and let them sit for a few hours - then rinse with water.  IMHO, better than the carb/parts cleaner that you get at the auto parts store and a lot less messy to deal with!

[BobbyR]

Simple Green does not react with the metal.
Back to the question, all of the blow dryers and other suggestions are valid. There is no way to long term soften the rubber. The additives used to make it soft have left for good. You can still get new rubbers and they are not all that expensive. When you put everything back together you may want to consider new rubbers. They will seal better and last of course for years.

[cleveland]

Heat gun and a little bit of engine oil on the boots.

[flatblack]

Simple Green does not react with the metal.

Yeah it does:

http://www.army.gr/html/GR_Army/dieuthinseis/DAS/flightfax%5Cff2000%5Cffmar00.pdf  (see page 5)

http://www.mach1registry.org/forums/archive/index.php/t-57271.html

http://www.safetycenter.navy.mil/media/mech/issues/octdec00/LettersToEd.htm  (see the last LTE)

This link is to a rather extensive study's results:

http://www.p2pays.org/ref/14/13872.pdf

That study found Simple Green "incompatible" with some steel alloys, too.  Hydrogen embrittlement is the technical term.

Here's a link to someone who blames Simple Green for eating a *bicycle* chain.  That jury seem to be out still:

http://www.velonews.com/tech/report/articles/9216.0.html

Anyway, Extreme Simple Green is formulated to prevent these results.  From the company's Web site:

"Extreme Simple Green® Aircraft & Precision Cleaner is a breakthrough water-based formula that cleans engines, aircraft, vehicles, metals, plastics, high-tech alloys, and parts. This non-corrosive, low-foaming cleaner/ degreaser does not contain reagents that oxidize finishes, cause rust or degrade elastic materials such as rubber or vinyl-but protects the life of hoses, seals, gaskets, paint finishes and other hard surfaces plus rinses residue-free for ease of use and protection of structures and finishes."

Kinda makes me wonder what's in the original stuff.  And why they came up the newer version...

If you use Simple Green on metal, be advised.  And thoroughly rinse it off.

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[BobbyR]

The bike chain yo yos were storing their chains for up to 5 years in the stuff. A couple of hours won't hurt the pot metal of the carbs. It is a real good solution for avoiding volitile fumes- and it works better. I did the testing and reported my results in a post last winter. Cleans better than Gumout.