Author Topic: Carb cleaning - where to start?  (Read 2448 times)

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Offline stereosilence

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Carb cleaning - where to start?
« on: March 04, 2012, 03:44:53 PM »
I am ready to sync my carbs for the first time and was thinking it would probably be a good idea to clean them. I have seen people say to take every piece apart and soak it in Simple Green, but that seems like overkill (and riding season is at the door). Is there a way to do a less thorough cleaning that I could do in an hour or two?


Offline Dimitri13

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Re: Carb cleaning - where to start?
« Reply #1 on: March 04, 2012, 04:13:19 PM »
My suggestion is to take the few hours and give it a proper cleaning.

Offline Bob Wessner

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Re: Carb cleaning - where to start?
« Reply #2 on: March 04, 2012, 04:33:24 PM »
My suggestion is to take the few hours and give it a proper cleaning.

Ditto.
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bollingball

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Re: Carb cleaning - where to start?
« Reply #3 on: March 04, 2012, 04:50:54 PM »
Plan A  About the only short cut you may get away with is to leave the rack together. But every thing else needs to come apart and cleaned. both jets float level check all pasage ways verified to be clean and free of blockage. Just depends how bad they are. However if the rack stays together how would you know all the connecting pipes are clean?

Plan B Take them completely down and do it right the first time.

Offline Gordon

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Re: Carb cleaning - where to start?
« Reply #4 on: March 04, 2012, 05:01:54 PM »
Plan A  About the only short cut you may get away with is to leave the rack together. But every thing else needs to come apart and cleaned. both jets float level check all pasage ways verified to be clean and free of blockage. Just depends how bad they are. However if the rack stays together how would you know all the connecting pipes are clean?

Plan B Take them completely down and do it right the first time.

IMO, Plan A is almost always all that is necessary.  Of all the racks of carbs I've cleaned and rebuilt, from bikes that had been neglected and wasting away, I have yet to have to de-rack any of them.  It's the jets and small passageways in the carb bodies that get gunked up and clogged.  The fuel supply lines can be flushed out with the carbs on the rack.

Offline harisuluv

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Re: Carb cleaning - where to start?
« Reply #5 on: March 04, 2012, 05:24:05 PM »
I always like to do a full teardown and rebuild.  If I am going to get in there I don't want to be taking them off all over again and getting in there again.  By the way, simple green will discolor aluminum if you leave it in there for more than about a half an hour, so be careful with that (bodies are ok of course)

Offline BeSeeingYou

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Re: Carb cleaning - where to start?
« Reply #6 on: March 04, 2012, 05:24:06 PM »
Plan A  About the only short cut you may get away with is to leave the rack together. But every thing else needs to come apart and cleaned. both jets float level check all pasage ways verified to be clean and free of blockage. Just depends how bad they are. However if the rack stays together how would you know all the connecting pipes are clean?

Plan B Take them completely down and do it right the first time.

IMO, Plan A is almost always all that is necessary.  Of all the racks of carbs I've cleaned and rebuilt, from bikes that had been neglected and wasting away, I have yet to have to de-rack any of them.  It's the jets and small passageways in the carb bodies that get gunked up and clogged.  The fuel supply lines can be flushed out with the carbs on the rack.

I am with Gordon on this.  If I remember this bike ran fine when you got it..am I right?  As long as they are not gunked up from evaporating gas I see no reason to disassemble them completely.  I know that is somewhat of a fetish here but it often seems more like self flagellation and so they want us all to suffer too. ;D ;)

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« Last Edit: March 04, 2012, 05:26:43 PM by srust58 »

bollingball

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Re: Carb cleaning - where to start?
« Reply #7 on: March 04, 2012, 05:34:37 PM »
I had to de-rack mine because the felt dust washers were gone pd42b and I didn't know how important they were. Other than that I agree I would leave the rack together.

                                                      Ken

Offline BobbyR

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Re: Carb cleaning - where to start?
« Reply #8 on: March 04, 2012, 05:53:11 PM »
Clean them really good on the rack, really good and u will do it once. I cut corners and did it 3 times.
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Offline stereosilence

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Re: Carb cleaning - where to start?
« Reply #9 on: March 04, 2012, 08:03:08 PM »
So, to clean them on the rack...I take all 4 of them off while they stay connected to each other, then submerge them in simple green (for how long?) and then what?

Offline BobbyR

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Re: Carb cleaning - where to start?
« Reply #10 on: March 05, 2012, 08:40:34 AM »
I probably was the first to post about Simple Green on here.  I did it by accident. I think people get to happy with that stuff.   
It is great for float bowls to dissolve the crap at the bottom and plastic floats. It does react to metals, so I would not submerge the rack in there.
Cleaning out the internal circuits is best done with spray carb cleaner and some strands of copper wire. The carb cleaner loosens some of the crud, the wire mechanically loosens and that sticks in there, and some spay cleaner flushes out the loosened crap. The secret is get the wire through every passage. Idle jets are very prone to blockages and you find white deposits on them. That is MBTE they used in gas some years back. Nothing seems to dissolve it, it needs to be scrubbed off.
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But we were boys, and boys will be boys, and so they will. To us, everything was dangerous, but what of that? Had we not been made to live forever?

Offline liPPy

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Re: Carb cleaning - where to start?
« Reply #11 on: March 05, 2012, 08:44:17 AM »
I used Simple Green, left them in too long (overnight) and was faced with a white residue across much of the carb surfaces as a result of chemical interaction between the strongly basic (high pH) cleaner & the alloy of the carb bodies.

I guess you could soak them for a shorter period - SG recommend no more than 10 minutes (!) -  but when I clean them again I'll be using a dedicated carb cleaner.

From the SG website:

"Aluminum - Is it safe to use Simple Green® on aluminum?
When used with caution and according to the instructions, Simple Green All-Purpose Cleaner has been safely and successfully used to clean aluminum. Simple Green All-Purpose Cleaner, Crystal Simple Green® Cleaner/Degreaser, Simple Green Pressure Washer Concentrates, and Pro Series™ Simple Green® Automotive Cleaner have been used on aircraft, automotive, industrial and consumer aluminum items for over 20 years. However, caution and common sense must be used: aluminum is a soft metal that easily corrodes with unprotected exposure to water. The aqueous-base and alkalinity of Simple Green All-Purpose Cleaner can accelerate the corrosion process. Therefore, contact times for unprotected or unpainted aluminum surfaces should be kept as brief as the job will allow - never for more than 10 minutes. Large cleaning jobs should be conducted in smaller-area stages to achieve lower contact time. Rinsing after cleaning should always be extremely thorough - paying special attention to flush out cracks and crevices to remove all Simple Green® product residues. Unfinished, uncoated or unpainted aluminum cleaned with Simple Green products should receive some sort of protectant after cleaning to prevent oxidation.
Simple Green has also developed break-through water based cleaners that are safe for use on metals, plastics, rubber and high tech alloys. Extreme Simple Green® Aircraft & Precision Cleaner and Simple Green® Pro HD are available on both the industrial and retail markets, respectively. These products were initially developed for the aircraft industry and extensive testing shows that they are safe and effective on a variety of metals and other sensitive surfaces even in the most extreme circumstances."


Offline BobbyR

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Re: Carb cleaning - where to start?
« Reply #12 on: March 05, 2012, 09:59:19 AM »
That is why I recommended float bowls. You fill the insdie of the bowl with 100%. Let it sit for an hour and pour out the junk. You may get a white spot or two that comes right off. The whole carb may be more of a problem. The carb bodies are not pure aluminum, it is some sort of cheap mystery alloy of aluminum.
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But we were boys, and boys will be boys, and so they will. To us, everything was dangerous, but what of that? Had we not been made to live forever?

Offline Bob Wessner

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Re: Carb cleaning - where to start?
« Reply #13 on: March 05, 2012, 11:02:03 AM »
Perhaps?;

"Pot metal, also known as monkey metal, white metal or die-cast zinc, is a colloquial term that refers to alloys that consist of inexpensive, low-melting point metals used to make fast, inexpensive castings."
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Offline BobbyR

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Re: Carb cleaning - where to start?
« Reply #14 on: March 05, 2012, 04:03:53 PM »
And yes Bob. "Carbs do Suck"  ;D ;D ;D ;D ;D
Dedicated to Sgt. Howard Bruckner 1950 - 1969. KIA LONG KHANH.

But we were boys, and boys will be boys, and so they will. To us, everything was dangerous, but what of that? Had we not been made to live forever?