Carb Cleaning

[craywm]

So, Took apart my first carb.. 10 years of varnish inside the bowls and jets.. scrubbed scrubbed scrubbed on one and got it partially clean. next day i went to auto-zone and picked up some carb and parts cleaner expecting it not to work. I like to boil my carbs before disassembly so that it goes smoothly. so i boiled a carb for about 5 minutes and popped the bowl in the carb cleaner (this is a dirty carb not the one i was previously working on) IT WORKED MAGIC!!! literally all the varnish melted away! threw the rest of the carb parts in there and it cleaned them all up very nice. the can said that it was good to use on alloys including aluminum. These are Mikuni VM aluminum carbs so i figured itd work fine. left the bowl soaking over night and pulled it out the next morning and it looked great! i boiled it again to make sure carb cleaner/varnish was all gone and blew threw it. It looked amazing. Moved onto my carb. Left it soaking for about 3 hours and removed it. IT CLEANED EVERYTHING PERFECT!! it said to only leave it in for 15-30 min maybe longer for dirtier jobs. after boiling, I noticed a distinct color change in the carb body. very much darker then before. I have read a bit about this but i did not think it was a problem and for a 3 hour soak.. it was an easy cost to pay for the outcome. I moved onto the next carb(the one i had worked on before) and took it apart. threw bowl in for about 30 min and took it out and boiled it. I decided to go with less timed intervals between boiling to avoid the discoloration. threw the bowl back in for about 35 min and pulled it out again and boiled it for about 15 minutes. took it off the heat and it was WAY darker than the first bowl. the carb body is still fine but the bowl is DARK! i dont want all my carbs to end up this way.. any pointers.. should i not boil them anymore? or is it just the carb cleaner? Thanks for the views and posts!!

 

[Steve]

Have you not read the VM carb cleaning guide in the Garage section? :-k
No mention is made of "boiling" the carbs, but for extreme cases like yours (10 years of neglect), we definitely suggest leaving the parts in "the dip" for a full day.

What carb cleaner did you get? The most popular, by far, is Berryman's Carb Cleaner Dip. If you can't find that, Gunk makes an equivalent.
Either one should be available in a gallon-size can (with three quarts of fluid and a dipping basket) for about $20.

I have only noticed discoloration when carbs were left in the dip (accidentally) for more than three days.

.

 

[Do Little]

http://knol.google.com/k/how-to-clean-a-motorcycle-carburetor-the-right-way#

Here's a decent article on boiling carb parts. I don't see why the bowls would change color just from boiling unless there was some coating or something on them. Unless maybe the carb cleaner soaked into the body then the boiling cooked it.

 

[Steve]

Here's a decent article on boiling carb parts.

It may be a "decent article", but he lost all credibility with me in the very first paragraph.

The title is "How to Clean a Motorcycle Carburetor the RIGHT Way".
OK, that's a nice start.

The part that lost me, though, was "So put your tools down for a minute, grab a beer, and give this a read."
Any time alcohol is required to perform a task, I will question the outcome.
I did not read very far past that statement.

I know many of you will disagree, and it's your privilege, even your right, but so is my opinion.

.

 

[sschering]

I have the NAPA brand carb dip.. (I think the enviro save stuff)
I've left a front master the can for 4 weeks with no discoloration or damage.
My carbs all got a 3-4 day soak to get the air screws to come loose..
again no discoloration or damage..

The stuff works awesome.. 10-20 min gets most things super clean..

short dips don't appear to effect rubber much but after 4 weeks the O ring for the MC cup was 3x it's original diameter.. still quite pliable and tho.. It didn't turn into a puddle of goo..

 

[craywm]

Steve: I did use berrymans from autozone. I believe it was Chem-dip. There first carb that i dipped i did not fully submerg it because there was no varnish on the head area. There was a FINE line of discoloration on the carb. I mean you can distinctly tell the difference in the color. I know that its not a huge deal and there are ways to repolish the bowls but its just frustrating. I know that with the bowl that was REALLY dark i tried to clean it with a steel whool. It was not a very fine whool though so i did not believe it would leave particles behind but this could have been why it was so dark. I dont really care about the inner carbs but the outer ones id like to look nice still.. I will post a picture of that full carb today. you can REALLY see the difference in the color from the bowl and the carb body! oh well live and learn i guess! but if anyone has any input on why this is happening then post it! id really like to keep my other 2 carbs pretty!!

ALL: I have read that how to clean a carb the right way. Was not too impressed by it. The most beneficial part of it was how he showed that its tedious and you have to have patience in order not to break a carb.. something i did not have at first.. and of course i broke a carb.. but JB welder fixed that up for me! Good as new now!!

 

[craywm]

P.S. I have also had luck with the carb dip and my floats. I do a five minute dip and wash them. Gets most of it off the metal and hard to get places. I try to scratch the rest off of the plastic with my needle. seems to work very well. always come out shiny!