FZR 600 carbs, only runs with choke on ???????? Help..

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wildcard
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FZR 600 carbs, only runs with choke on ???????? Help..

Postby wildcard » Mon Aug 17, 2015 4:25 am

Hello Guys, I am having some irritating problem with my 94 FZR 600 just got it a few weeks ago have gotten it running after I noticed the VR was missing, so I read a few good threads on here about the R6 VR install so I went ahead and wired and mounted one, anyway the engine will start and revs up but Will Only do this with the choke on, I have read extenseful threads on here close to the same problem and have removed the carbs cleaned all the bowls extensively, twice now, then read that the floats could be set wrong or naturally changed over time or setting, had one carb (#1) as the others, for instance when I would put my finger into the opening to move the slide up while running I noticed just as my finger kinda plugged the slight air opening in the venture to the slide bottom the #1 carb wouldn't do anything but with a short stick of the finger in the same area of the other 3 carbs it would raise the idel quickly until I removed my finger. still with the engine on pretty much full choke, so I removed the carbs again and set the floats to 24mm and reinstalled the carbs seems to have the #1 carb back online but the problem hasn't changed just runs a touch smoother now even with the choke still on, I read that if you don`t remove the idle mixture tamper plugs and remove the screws,spring,washer and oring that the carbs haven't actually been cleaned sind this area was the smallest ports and will clog pretty much first, So I just got back in the house from doing that and cleaning that areas again, I`m getting no plugging anywhere I spray carb cleaner it comes out the holes its supposed to., Only thing that has changed is now if you hold the RPMs up and shut the choke off you can rapidly turn the idle speed screw twist up to around 3k or higher rpm and when you try to turn the idle down (with choke off now) it get down to about 2-2500 rpm and starts to get irratic and any lower the idle screw setting any lower the engine dies and them won`t start on the choke till I turn the idle screw back out to alost shut and it will start instantly when you turn the choke back on, with the choke on you can shut the choke lever slowly and the rpms will come down but once they get to 2k or 1500k or lower the engine will die, move the choke wide open and most all the time just touch the starter button an it will fire and run at choke rpm, turn the choke off the engine will die.
If you try to start the engine with the choke off it fires once or twice like it wants to catch but just cranks and does not start, turn the choke back on a bump the starter and again if fires right off.

when I took the idle air tamper caps out 1,2,3 screws were all the way in and 4 was 1/2 turn out, for what I have read I have learned most have found it will run or factory default settings are 3 turns out so I went 2 1/2 and there is no difference for when I started with this problem so carbs have been off 4 times now in couple days and no change other than the one carb I was talkin about earlier that is workin better now, just seems like I`m getting no fuel to the engine antime the choke is off or it looses fuel charge almost immediately.

any Help would be appreciated, I have had the slides out and they all look good and it has a washer under the needle, didn`t pay attention to where the clip was, but this bike seem to never be tampered with until I got into it, I have been an Auto technichian for 30+ years and other than a couple non rebuildable junk Quadrajet 4bbl carbs I have always fixed and gotten everything else running good, have been in several of my snowmobile mikuni carbs like on my Skidoo Rev 800 twin and skidoo 780 triple sled and have always had good luck with cleaning them every season, but these bike carbs are a pain in my ass

Do I just have a set of Junk carbs of Whats the problem here?????

Please Help, Thanks Wildcard

4wred
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Re: FZR 600 carbs, only runs with choke on ???????? Help..

Postby 4wred » Mon Aug 17, 2015 7:33 am

Sounds like clogged dirty Idle,slow jet circuit.You said you cleaned the bowls??did you clean out the jets and their related passages?
Anytime I've had your problem on a bike I was working on it was usually clogged,plugged up slow jets passages.Oh and I agree with the quadrajunk carbs,that's what we called them!!

wildcard
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Re: FZR 600 carbs, only runs with choke on ???????? Help..

Postby wildcard » Mon Aug 17, 2015 11:34 pm

thanks for the reply, yesterday afternoon for the 3rd time removed the carbs and the bowls and reset the float adjustments at 24mm then since I had already had the slides out and the jet tower removed and the jets out and actually ran a guitar string thru the jet holes and used a ton of carb and brake clean in or on anywhere there was a passage or where gas would go or be, I reassembles the carbs again and reinstalled and still same prob will only run with choke on. put choke on full and touch the starter button and it fires right off and idles about 2-3k rpm you can turn the choke down an rpms come down but anything below 1500 engine dies, seems to rev up fine or kinda sluggish naturaly off the choke rpm and higher rpm seems to smooth out and is responsive just doesn't seem to rev much over 8-9000 or I haven't held it pinned to do so just quick braps of the throttle.

came back in the house last night and read a few carb thread of similar probs on here and read about removing the tamper caps and screwing out the ratio screws and cleaning the passages and sprayed carb cleaner thru the passage hole, pilot jet and port inside the venture and put carbs back together and reinstalled them thinkin this is it the clean process is complete and haven't skipped anything I got it but after reinstalling the carbs it does the same exact thing again,

Fuel pump thumps when you turn the key on or flip the on/off switch and hear the pump just thump a time or two after seems carbs have been filled, I cleaned the tank before I even started on the carbs a week ago, removed the fuel valve disassembled and cleaned tank had a touch of rust in the bottom but not a lot, I poored rustmort in the tank and let is set a few hours and then rinsed with water and following morning as the tank dried out I put fresh gas in and that's when I took the carbs apart the first time and cleaned them to go with a freshly cleaned tank, I can`t think of anything that would cause this problem????

Only thing that does wonder me is float pod on each side on a single float , 2 floats assemblies seem to be lower on one side then the other where when you touch the floats and watch then move or spring up and down the long end or 2 floats just graze the inside of the carb bodies like they have settled on one side but didn`t think this problem would cause failure to start or run on its own with out the choke figured this prob or if floats needed replace would cause a bit of flooding or problem somewhere else other than idle or reving with choke off,

Really bothering me on this prob, just curious if I should start over with another set of carbs? Does anyone out there have a good running set of carbs that you
would be willing to sell reasonable.

Let me know what ya think and please comment on this, I see a lot of these thread get a lot bigger number or lookers but no posters.

Thanks, Wildcard

wildcard
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Re: FZR 600 carbs, only runs with choke on ???????? Help..

Postby wildcard » Mon Aug 17, 2015 11:45 pm

Also when I remove the idle mixture or ration screws I counted the numver of turn they were from stock, 1,2,3 were all the way in and 4 was 1/2 turn out, I
comeback in the house brank up the carb thread and read that 3turns was stock and most have foun 2-3 runs was a starting point so I set all carbs at 2 1/2 turn out and still, absolutely same problem still.

Thanks, Wildcard

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willandrip
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Re: FZR 600 carbs, only runs with choke on ???????? Help..

Postby willandrip » Tue Aug 18, 2015 4:45 am

You still have some restriction on the pilot circuit.
Have you cleaned the airway passages ?

I would discard the original pilot jets at this stage and replace.

Here is a link that shows the circuit operation.
(Each pic. may be expanded once loaded by placing the cursor over the square box in the bottom of the pic.)

http://www.400greybike.com/forum/viewtopic.php?f=35&t=12571
Sent from my keyboard using the English language not some teen text shite from a fooking phone.

wildcard
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Re: FZR 600 carbs, only runs with choke on ???????? Help..

Postby wildcard » Wed Aug 19, 2015 12:19 am

Hello Guys, Thanks so much for all the replies and You are right I had a restriction in the Pilot Jets, All the times I had the carbs out I didn`t have a good enough small screwdriver to get the pilot jets out I stuck a guitar string down the bore in where the jet set and though it was going in the hole but to learn tonight I took the carbs off for the 5th time and took them to my work where all my better tools are (I am a Transmission Tech and Auto repair) so all my good tools are at Shop where I work. anyway I took carbs all the way apart keep the the rack assemble together and found a good craftsman small screwdriver and got the pilot jets out and Holy Shit is the hole in those babies small. even with my reading glasses on I could hardly see it so my small guitar string wouldn`t even fit.

I couldn`t blow thru 3 of them with my mouth and I spray some carb cleaner in the like on the can and then tried to blow the little extension tube you put on the top spray nozzle of the carb clean can and tried to blow cleaner thru the threaded end of the pilot and only on jet you could see a small stream coming out the end hole, So since Oreily`s auto parts is literaly next door I went over and bought a can of Seafoam and poored some in another can lid and let the pilot soak for about 20 minutes after doing this it cleared up 3 pilot jets but took a lot longer on the last one finaly they all blow cleaner thru them evenly, and as they were soaking for the last time I sprayed cleaner thru the tiny holes under the nozzle all the jets are in and could see it coming out the center venture, 2 tiny holes together in the center and a bit bigger single hole up the side after doing this to pretty much every passage I could fine all flowed evenly and gave the pilots one last spray thru and Finaly good flow.

Put carbs all back together come home put them on the bike and pulled the choke open hit the start and instant start, seconds after than I shut the choke off and idle went to 4k cause I had the idle speed screw cranked up from the other night reached under and twisted it and the idle down to 1500 and wow what a difference never touch the choke again and it would rev quickly and responsive, I`m sure it will be better once the air box is back on

So happy now , :cheers: I was litteraly gonna order another rack of carbs and start over.

I am also getting a friends 86 Kawasaki Ninja GPZ 900 running and thought I cleaned the carbs on it good just hadn`t tried to fire it since, but now I`m taking them back off and redoing a Good Thuro Clean on them like my bike and hope that all works good.

Thanks Guys for setting me in the right direction, Hope someone else benefits from this thread, Never under estimate just how clean you think you have these carbs, with out removing the tamper plugs and the ration screws along with REMOVE THE PILOT JETS and make sure they are visualy clear. banghead

Wildcard


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