I'm currently cleaning the carbs. There's a bunch of dirt on my diaphragms - is it ok to clean these with a dawn/water spray bottle combo? Have done a bunch of searching online but haven't found any info beyond the standard DONT TOUCH THEM WITH CARB SPRAY!!!!!!! Do you all use anything to clean these diaphragms.

Bonus question: I've looked all through these forums - the needles out of the slides are not coming out of the carb slides. I know I must be an idiot and missing something but the few videos I've looked at look like the needle easily slides out but this isn't the case for these carbs.


Thanks for any help!!!!!!

Water alone will probably be sufficient to clean the diaphragms. I wouldn't be afraid to use a little dish detergent, like you suggested.

However they shouldn't be dirty. How did dirt get in there? May explain why your needles are stuck. On both sets of carbs I have the needles literally fall out. Could be dirt or corrosion or both in the needle and slide interface. If it was me I'd try a little WD-40 in the hole from the top side and see if soaking it doesn't free the needles. Or conclude that this is all wrong and replace them. Or the whole carb.

Has this been under water?

I've just used a shop rag to wipe the diaphragms clean.  Never needed anything more.  If I did I'd go for Simple Green mainly because it's safe for rubber and I have it at hand (great for cleaning carbs in the ultrasonic machine), and rinse thoroughly afterward.

There's nothing holding the needles in the sliders aside from gravity and spring pressure on the nylon UFO washer.  If yours are stuck, soaking them out sounds like a good idea followed by replacement along with all the other brass bits and O-rings that come in a full rebuild kit.  Don't forget to pull and clean the plastic slider guides that come out with the emulsion tube.

Simple Green is not so great on aluminum parts. The stock needles are (probably) aluminum. I would avoid it as something to soak the needle/slide assy in.

FWIW you might just get away with a tap to free the needles. I still would wonder how they got stuck.

So I had to pull the needles out with a pair of pliers. My GS500 is an 01. It looks like these needles are designed to click in. after pulling them out and reassembling the carbs, my slide diaphragm needles were not working properly - when I pulled the vacuum cap off I discovered that the the spring and head at the top of needle assembly had moved and the washer on one of the needles had fallen off. There's a very natural click into the seat that the "head" (plastic piece the spring sits) sits in and this solved my issues.

Is it possible post 2001 carbs are different in this way. It's very clear these are meant to click in.

@mr72 I think water must have gotten on these carbs at some point because when I first got them there was way too much rust. Also thanks for your awesome guide on carbs on your blog - was a huge help in cleaning them for the first time! Unfortunately - It looks like I'm missing one of the small vacuum cap orings which I'll have to order.

Quote from: restless on August 27, 2018, 12:57:21 PM
@mr72 I think water must have gotten on these carbs at some point because when I first got them there was way too much rust. Also thanks for your awesome guide on carbs on your blog - was a huge help in cleaning them for the first time! Unfortunately - It looks like I'm missing one of the small vacuum cap orings which I'll have to order.

Really glad it helped!

BTW those vacuum cap o-rings are of a common size you can get at most auto parts stores from their little assortment bins. The super tiny o-rings on the pilot needles are another story...

Quote from: mr72 on August 27, 2018, 09:31:34 AM
Simple Green is not so great on aluminum parts. The stock needles are (probably) aluminum. I would avoid it as something to soak the needle/slide assy in.

FWIW you might just get away with a tap to free the needles. I still would wonder how they got stuck.

Good to know, thanks!  I'd suspect most any detergent would be bad on aluminum due to their alkaline nature.  However it does a nice job on carb residue.  I've been using a 50% solution in the ultrasonic at the recommendation of an engineer friend.  Mind you, it's only in for a short time, maybe 10 minutes.  I do rinse everything thoroughly after and the results are worth keeping but I'll keep your warning in mind.  Maybe do some testing to see what things look like after a day, week, etc.