careful with those float pivot pins

[mikenixon]

Hmm, no, I wouldn't do that. Silicone in my view doesn't belong anywhere internal on an engine, including the carburetors. Think cholesterol for engines/carbs. Spoke nipples (dirt bike guys used to do this), brake anchor bolts (before thread lockers became common), and elsewhere, but all external, no internal. Besides, gasoline and silicone and known to not get along well. In fact, personal watercraft techs actually use gasoline as the solvent of choice to remove the silicone sealer that seals the jet pump to the hull (it softens it).

Not to put too fine a point on it, but I have more to say about silicone sealers on my website. The bane of the industry, as far as I am concerned.

http://www.motorcycleproject.com/motorc ... ctice.html

Granted, you are in the experimentation mode and aren't dealing with a roadworthy motorcycle, but still....goes against my ethics somehow...

[DocRoot]

Thank you

[mikenixon]

I probably should add that I realize marred float pivot pins aren't the only cause of broken float pivot posts. Attempts to get the pins out when the whole assembly is crusted over with crud is probably the primary cause. One of the advantages of using an ultrasonic cleaner is its ability to free up such pins before attempts are made at removal. I also use an ultra skinny drift punch I had to make myself as I never could find one. Been using the same one now for nearly 23 years.

However, I will reemphasize that using pliers to remove these pins is a sure path to carb casting destruction. The posts were just never designed to withstand a lot of pounding...

[DocRoot]

I use the smallest screwdriver in my eyeglass screwdriver set for driving the pin out (following the advice of not holding onto the carbs so they can move to limit the force). The next larger screwdriver is perfect for cleaning burrs out of the holes.

[robin1731]

Suzuki tech school teaches, or at least used to, to use a spring loaded center punch on stubborn float pins. You can set the pressure with the handle. I've used that method for years. You do need to make sure you have something on the opposite side you are pushing on though. I've seen pins get launched when the spring hits.

[mikenixon]

Suzuki tech school teaches, or at least used to, to use a spring loaded center punch on stubborn float pins. You can set the pressure with the handle. I've used that method for years. You do need to make sure you have something on the opposite side you are pushing on though. I've seen pins get launched when the spring hits.

Yeah, Suzuki has that in an old training video. It's a good technique. One of the manufacturers also taught a method whereby you gently clamp the two posts together...and there are other techniques. One of the big advantages of having an ultrasonic is (I was surprised to discover) how it frees up the pin. On stubborn ones I will put the carb intact into the tank temporarily to loosen things up. Does that with stuck slides too.

[DocRoot]

I will put the carb intact into the tank temporarily

Will an ultrasonic damage anything in an assembled carb?

[mikenixon]

Obviously I don't keep carbs intact for any other reason than to loosen stubborn parts. Say an hour or less in the tank. Then out, apart, and properly segregated and the parts individually cleaned and the castings' passages properly dealt with. No, there is nothing that can be hurt. The rubber diaphragms on later Wing carbs I try not to expose too long, just for general purposes. But no, there's no worry.

That said, a professional level ultrasonic does have to be used carefully. A 250 watt or higher unit can remove zinc plating if it is heavily oxidized and about to come off anyway, which quite a few carbs' plating is. Zinc was put on very thin at the factory and 40 years of exposure usually results in it being only a breath away from not existing at all. The same with paint (which I don't like on carbs) and of course the clear lacquer found on the vacuum tops on GL1100s. I generally strip the lacquer off and polish anyway, but you see what I mean.

[robin1731]

Mike what do you use in your ultrasonic cleaner. I use a mix of simple green and distilled water. Works well. You don't want to leave aluminum parts in for an extended period of time though.

[mikenixon]

I think the solutions available for ultrasonic cleaners are like the beverages at restaurants -- it's where they make their money. You can pay a lot of money for these chemicals and in my view even the most exotic ones don't get very far from what most rebuilders agree is the basic formula, a few drops of old-school dishsoap for each gallon of distilled water. Rebuilders I know have got away from Simple Green because it is very high PH and thus interacts too aggressively with cast aluminum. The word is that Boeing led some research into codifying this, as they were early adopters it seems. If you are using Simple Green at mixes weaker than 5:1 in my view you have the equivalent of soap/water right there. If stronger, I would recommend some vinegar be added to lower the PH and reduce the tendancy of the carbs to grow white fuzz. Here is a useful link on the subject.

http://www.motorcycleproject.com/motorc ... ing_v7.swf

[robin1731]

snip......... If you are using Simple Green at mixes weaker than 5:1 in my view you have the equivalent of soap/water right there.

Yeah, my ratio is less than that. And like I said, I don't leave stuff in very long. In the beginning I left some float bowels in over night. That's How I found out that isn't a good idea. Even with a weak mixture.