Carburetor Strip And Soak

[xExcessive 1120]

Having read all the threads I could find on carburetion I have purchased a gallon of NAPA carb cleaner and using an old partial rack of '78 (2H7) carbs, pulled off the rubber boot on the enrichment plunger and a rubber-coated "T" connector and plopped them in a small glass bottle with the cleaner (It needs to be shaken even though there is no such instruction on the can) to test their resistance to the solvent. Well the bottle turned pitch black in twenty minutes. It ate them up! So I read the thread of 06-16-2002 posted by xs11 entitled "Carb Cleaning Disassembly Tip". On page two of two is pictured a needle with a washer and a rubber O-Ring. I do not wish to ruin any vulnerable bits, so need to know is this part or any other disappearable piece to be found in my carbs? I am pipping to get my sidecar rig on the road, so any help will be much appreciated. Thanks, Christopher "The Gimp"

[xssiveone]

Yes, there are several rubber parts that will be ruined by cleaning them in the manner you've described.

You say you've just

plopped them in a small glass bottle with the cleaner

without complete disassembly... you can't get them clean on the inside like this.

But, back to the rubber bits. There is probably a rubber O ring on the idle mixture screw, there is a rubber O ring on the starter enrichment plunger, there is a rubber diaphram on the top of the carb slide, and there are 2 rubber seals on the throttle plate shaft. Spray carb cleaner is the safest method, followed by compressed air thru all passageways.

The throttle shafts are the most difficult to remove as the screws are peened over once installed to prevent them coming out and getting sucked into the engine.

[xExcessive 1120]

Vulnerable Rubber Carb Parts

Thank you Brian, I will go easy with the "wonder juice". That NAPA cleaner sure makes the brass shine. On an unrelated but great discovery is an Australian named Brian Cutler who is making replica badges for restorations and has produced some beautiful sidecover badges for the Standard and tank badges for the Special and can be found at: http://www.badgereplicas.com.au Once again thank you very much for the quick response to my query. Christopher "The Gimp"

[xssiveone]

You're welcome, and good luck with your carb cleaning project. I probably should have mentioned that I went the "dunk and soak" method for cleaning my carbs.. complete disassembly, including the throttle plates and shafts. And after putting them back into service, proceeded to take them off again and clean them once more with spray carb cleaner.... so am hesitant to say which method is best. For the time and effort involved, the spray cleaner probably works just as well as the other.


If you check the forum, you will find many references to the infamous carb "triple clean". This comes from people having to remove and clean the carbs at least 2-3 times. There are so many small passageways that can become restricted or plugged that it is difficult to get them all the first time. One you do get them clean, run a can of cleaner in the tank at least once a year. Sea-Foam has produced very good results for people, but there are others that work as well.

[prometheus578]

I would recommend not removing the throttle plates. Sometimes they are machine fit to their individual carbs, etc. I've had customers rebuild their own carbs and then bring them to me when they don't work right. Things like putting the throttle plates back in backwards, upside down, or in the wrong carbs where they don't match up. It can be done, but mark each plate in some manner, such as scratching them #1, #2, etc. Loctite might be a good measure upon re-assembly. Don't forget to sychronize them when finished. That is a must!

[pgg]

The quickest way is to suck them clean at 8000 revs in neutral by sealing each carb intake for a few seconds.

[skids]

Throttle plate axles have rubber o-ring seals that swell-up in soak solution and foul the movement. Here is a link to spray clean carbs and it has worked for me many times. It is not well-written, but you may be able to follow it...
http://home.earthlink.net/~sidskids/carbs/spraycarb.htm

Originally posted by prometheus578
I would recommend not removing the throttle plates. Sometimes they are machine fit to their individual carbs, etc. I've had customers rebuild their own carbs and then bring them to me when they don't work right. Things like putting the throttle plates back in backwards, upside down, or in the wrong carbs where they don't match up. It can be done, but mark each plate in some manner, such as scratching them #1, #2, etc. Loctite might be a good measure upon re-assembly. Don't forget to sychronize them when finished. That is a must!