Carb clogged¿?

Noidea

Noidea

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whats up guys as some of u know been trying to get my bike up and running in proper condition I got the timing down it still needs some loving tho waiting for my light to come in so while doing that figured I go in the carbs and figure out why I have basically no idle. First I took left carb out cleaned and inspected everything was fine only thing was I have a little crack in the diaphragm so I put electric tape over it I wasn't sure what else to do. and I moved the clip in the needle to factory setting of the 4th ring from the 3rd . I proceded to take of the left carb to find that it was super dirty with carbon there was black soot all inside. This got me sort of excited seeing as though iIl be able to find the problem. Checked everything out and all was clear then I tried to clean the air holes out built within the carb and found that one of them won't let me clean it out. It seems to be clogged up but I'm not sure if it's just supposed to be like that. I read the carburetor guide and it states that it's an air flow so I should be able to spray cleaner through it correct?¿ nothing goes through. The hole I'm talking about that doesn't allow anything in has an m next to it and the one that works doesn't have any letters next to it. If this is true this could be the problem to my rich fuel mixture and no idle? And how do I get whatever is in there out? with an air compressor? Sorry for the shitty pictures that was the best I could do:) thanks guys
 

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I would take the tape you put on the diaphram off clean it good with carb cleaner let it dry and patch it with Walmart's Shoe-Goo
or a good silicone..... the air blead holes take a super fine wire to clean.... the only thing I found small enough was a wire plucked from my wire brush..... not even my smalles torch tip cleaner was small enough to go in them......
My experience on these older carbs is severly limited so take what I say with a grain of salt.....
replaceing the cracked diaphram would be best by far instead of patching it. but you do what ya gott'a do !
..... 2M won't stear you wrong, follow what he says and it will soon be running
..... Bob.........
 
I'll chime in that a carb should not have a bunch of carbon inside. Time for a compression and (DIY) leak down test. I'd take odds on a fuggled intake valve. A chunk of carbon (now pounded on) the seat would not be rare. When cleaning small jet orifices think about the direction of flow. Whatever plugged that jet came in from the intake, it will go back out the same way ie get compressed air or carb cleaner directed at the BACK side of the hole. I mainly use copper wires for cleaning unplugging duties, Countless jets have been ruined by cleaning with torch cleaners, guitar strings, and the like. The hole is a finely sized metering device, random auguring out will not improve your bike's runnning. But for REALLY tough plugs in tiny hoIes I have sharpened a piece of stainless steel safety wire on a fine grinding wheel, LOL. You may want to look at your air filtering also, why was there a chunk of something big enough to plug your carb in there?
 
Noidea, trying to seal a bad diaphragm with tape, adhesives, etc. is a waste of time. 1. The defects you're trying to repair are present because material you're working on is breaking down, and that material will continue to break down. 2. Shoe-Goo, silicone sealers, etc. will break down due to fuel fumes and leave you with more of a mess than you started with, and tape won't adhere long for the same reason.

There are only two proven fixes: new slide/diaphragm assemblies, or new replacement diaphragms from JBM Industries. JBM diaphragms are the better choice for two reasons. You're assured of fresh rubber (as opposed to NOS material that has sat around offgassing for 40-plus years) and excellent material and quality control (as opposed to Chiwanese repops made from recycled condoms). They're more economical as well.

+1 on Gary's cautions re. those "holes." If you had read the Carb Guide, you would know that the "hole" with the M beside it is the main circuit air jet. A compressor with an air gun with rubber tip and needle tip is your friend here. Aggressive cleaning has ruined many carburetors.
 
grizld1 said:
JBM diaphragms
Click to expand...
I've read that these don't have the cloth layer originals do and that they don't last long because of it.
I would not automatically discount "Chiwanese" anymore. The worldwide infrastructure is running on it...
 
To bob kelly yea I've heard carb cleaner is bad for you diaphragms as it could dry them out. In my right carb i just cleaned it off as much as i can and put some petroleum jelly on them to bring them back to life so they are not so dry I've heard you can do this for gaskets and such to increase their life span. I was thinking i could use silicone for the crack in the left diaphragm as well but wasn't sure so just put the tape as i didn't want to ruin it.

To gggary maybe i misworded what i meant or dont understand what you mean i just meant it was sooty same as the spark plugs are there were no solids found in the carburator lol but i got whatever was in that orifice out thannks:)

I followed the advice of grizld1 and used an air gun to clear the hole worked like a charm. Im about to order the jbm carbs the electric tape will have to do for now. Till i order those JBM diaphrams
I realized that the airboxes have a connection between them and one of them had a clamp around them so i figured Id get another clamp to compliment it. i did that and put everything back together i have stock setup with carbs
o ring on the 4th ring on the needle
idle screw turn .75 of a turn
stock jets ( or what im pretty sure is stock)

Im still sort of having the same problem bike idles a little better but overall when riding it and stop at a red light or stop sign bike shuts off without gas as if i hit the cut off switch. Theres really not much idle The spark plugs are also still rich Still dont know what the problem is im assuming it has to be a carburator related.Im not quite sure what else it could be.

I don't have a right muffler because the baffle inside broke i believe that would be a problem. If anybodies got any ideas help a brother out cause as you see i got NON hence the name thanks again
 
yes Carb cleaner will dry out the Rubber and remove any trace of oil...that is the point ! that is Nessarry if you want the silicone to stick to it good !!!!
AFTER it dries real good like 48 hours or so..... in the sun ! then you can add the oil back into the rubber, I like WD-40 for that
as it's thin and goes on evenly..... soak them and set them aside... to drip-dry or you can use the vasoline or Greese.
that old diaphram would last you years more if you do that but , if you have the money to replace them DO SO !!!!!!!!
beats pushing the bike home on a dark night ! because hodge podge repairs like I sujested can fail ! you should already know that !<grin>
but if your short on cash as you mentioned before then that trick will get you by for a while ! ....I know I've done it !
Most of these guys will tell you things Must be replaced in order to run again, or classify it to being "Right".... and their correct ! but not everyone is rolling in money, and want just a fix to get the thing running so they can ride it to work.... because the car takes too much money to operate.... that's where I'm coming from you gave me the impression that you needed to conserve spending as much as possable..... well thats one way because the diaphrams are not cheap ! .
....
Glad you got the obstruction out if the passage ...it's amazing how hard it can be to clean the passageways some times
.... you need to do a Dead cylinder test/adjustment on the idle airscrews..... you can find that in the carb section of the technical refrence on this site....
this may well cure the idle problem as well as the periodic pop back your experiencing
my idle air screws were set at 3/4 of a turn out from the seat I ended up with them at about 3 turns out from the seat..... I have vurtually the same machine as you do I believe.... a 82'xs650 Heritage special..... the carb section goes over it in detail.... you need to read it !
.....
hope that helps !
Bob.........
 
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noidea, My 2 cents..........Your a newbie so some advice. You have Grizld1 offering advice. He and 5 Twins wrote the carb Guide and if any one knows how to tune CV carbs he is one to listen to.................I have seen him help, people work on, clean,rejet, and tune sets of carbs on here when questions were asked............ These people listened and worked trough the process, and at times, the questions were repeated till the owner got it right....................More times than i can count i have seen him walk away because the OP was not helping himself and not taking the advice when given...............reading the carb Guide in conjunction will help will make it easier......While your carbs are apart make sure you know the size of your jets, if they have been changed it is important to know their size, Standard jetting can be any one of 3 sizes as recommended by Yamaha so needle clip can be different depending on the jet size. Jets hardly wear out so 99.9% of time they just need a proper clean ..... First link in this thread is the carb Guide http://www.xs650.com/threads/carbs-carburetors.43/

It takes a while to know who's or what advice is the best for a situation, If your not sure do some research on us through our profile pages.....Even do some googling on or around the area being worked on.............

A 73TX has BS38's........as per your pics.............Carbs changed every 2 years and even though the BS38's carbs were used from 71-79 the jets and jet needles changed as well, as did the bowls.

$48.00 for a set of diaphragms delivered to your door. Money may be tight i understand..............The diaphragms are delicate enough to control the lifting of the slides when the throttle gets to a certain point. they lift by vacuum........If for any reason the flexibility of the diaphragm is compromised it will reflect on tuning, hence bike operation.............
 
No, listen to Kelly, he'll tell you how to fix it. I'm not getting involved in a thread in which I have to argue with somebody who knows it all.

PM if you need help, but here's the Golden Rule of carb repair and tuning: Everything else first.
 
Maybe. Specs say max temp 140* F and not recommended for rubberized cotton, application says it's an adhesive, not a sealant, don't know what would happen if used without a patch or what you'd use for a patch without affecting slide lift. Might work, might work for only a short while, but if it fails the old BS carbies will let you limp home with perforated diaphragms anyway. Any brave soul want to give it a test?
 
oh for God's Sake Grizld1.... PLEASE take OVER here ! You already know I have no expertise on these older machines at all....
I'll shut up and leave you too it.... it first seamed like nobody wanted to talk to him so I took it on .... please feel free to take it over guys Your help is better than mine by far !
..... I'm out'a here ....
good luck Noidea !
Bob.........
 
grizld1 said:
Maybe. Specs say max temp 140* F and not recommended for rubberized cotton, application says it's an adhesive, not a sealant, don't know what would happen if used without a patch or what you'd use for a patch without affecting slide lift. Might work, might work for only a short while, but if it fails the old BS carbies will let you limp home with perforated diaphragms anyway. Any brave soul want to give it a test?
Click to expand...
I wonder why the caution about rubberized cotton. Could be because of a kind of rubber typically used for that. Good patch might be cut out of very thin silk, or maybe cheesecloth. Or possibly something like saran wrap or dry cleaner bag. My gut feeling is it would take quite a huge glob to have any negative effect on the slide. Like a really, really, really huge glob.
 
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I wasn't concerned so much about the amount of the adhesive as about flexibility and the effect of the patch. Silk doesn't hold up very well to heat (lessons learned in Tehran carpet shops back in the pre-Khomeini days), but it might work. And if it doesn't, you're only out the price of the sealant and a very little time. I hope somebody gives this a try. (I would, but I'm not about to pull my flat slide pumpers, mount an air box, and refurb a pair of BS38's to do it!)
 
Listen up, Noidea. Everything else before carburetion. Otherwise you're just chasing your tail. Gary told you what to do first. When you have results from compression and leakdown tests, post them. You need a new muffler(s); you'll get nowhere with carb tuning running one side wide open and the other not. And you need to troubleshoot all of your ignition system: power delivery, timing unit, coils, HT wires, plug caps, the whole shebang.
 
Griz, I was successful in using the "spray plastidip" patch trick, found in those other threads. Of course, as a temporary fix only. Bad thing about that stuff is the acetone found in most carb cleaners. The acetone destroys the patch job...
 
TwoManyXS1Bs said:
Griz, I was successful in using the "spray plastidip" patch trick,
Click to expand...
I wonder if the stuff above could just be brushed on like plastidip. Might be like the plastidip fix with more balls (solvent resistance andor adhesion).
 

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