mleach72
Well-Known Member
I looked at pictures of your bike from earlier posts. It looks like you still have a breather line running from the crankcase to the air cleaner.
Am I supposed to stink like exhaust fumes when I'm done riding?
- Thread starter Matt300ZXT
- Start date
mleach72
Well-Known Member
If you have another breather line with a little filter on it, the PO probably got tired of that line pushing oil into the air cleaner and leaking out, so he ran it to the ground. That is fine, but I would still plug the 2 lower breather hook-ups on the ac.
Matt300ZXT
Member
Well I put it all back together, adjusted the carb to S&S starting specs and now the fucking thing won't even run. It started up and I was going down the road and it was backfiring like hell and power was surging. I get it in the garage and attempt to do the carb tuneup at idle and it is backfiring out of the carb inlet and won't stay running. The first adjustment of the idle speed screw wasn't doing a damn thing. Now I have a bike that ran but needed a little tweaking to one that won't run at all.
Edit: Ok I went back down in the garage after a few minutes of cooling off and reset the knobs again. I got the idle up a little so now it's wanting to idle better than it would before (didn't even have to use the enrichener) and did my best to tweak the idle mixture knob but it is now backfiring out of the exhaust and not the carb, though it did belch one small fireball out of the carb. I can't really tell much if the accelerator pump is working because most every time I go to blip the throttle it backfires before, during, or right after. But at least the idle is up and it doesn't seem to wanna die at idle, but now I can't tweak the mixture right because of the constant backfiring.
Edit: Ok I went back down in the garage after a few minutes of cooling off and reset the knobs again. I got the idle up a little so now it's wanting to idle better than it would before (didn't even have to use the enrichener) and did my best to tweak the idle mixture knob but it is now backfiring out of the exhaust and not the carb, though it did belch one small fireball out of the carb. I can't really tell much if the accelerator pump is working because most every time I go to blip the throttle it backfires before, during, or right after. But at least the idle is up and it doesn't seem to wanna die at idle, but now I can't tweak the mixture right because of the constant backfiring.
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mleach72
Well-Known Member
It's backfiring when you adjust the idle mixture screw? If it's idling ok, you should be able to adjust that.
Matt300ZXT
Member
I got the idle up to what sounds like a healthier sound (no tach so no clue the actual rpm) and I can actually start it without the enrichment tab now, but either something didn't go back together the same way it came apart or the tweaking of the idle adjustment screw is way off. I could tell when I turned it in, the bike almost wanted to die, so I started turning it the other way a little at a time, counting the turns, and it started backfiring out of the exhaust more. So no matter what I did with that screw, it wasn't helping. With those issues, I got the accelerator pump screw adjusted to probably where it should be, just the bike was not cooperating. I should have never touched this damn thing lol
Mikeinjersey
Well-Known Member
If you followed the instructions I sent in post 9 and the video Rottweiler sent in # 10 the bike should run at idle without backfiring. The acceleration pump is only used when Quickly adding throttle. No effect at idle.
Don't confuse idle mixture and idle speed screws. Go over the Video again and pay close attention to what is being said . The adj document I gave you is accurate but includes jetting which you should not be concerned with right now. If you can't get it to idle properly you may have an intake air leak or an exhaust gasket leak throwing the adjustment off.
When you turn in(clockwise) on the idle mix screw it allows less fuel/air mixture and out increases the fuel/air mixture. EXAMPLE Imagine an intake air leak after the carb intake and you can understand that the baseline adj of 1 1/4 turns out (counter- clockwise) from lightly seated would be lean because of the added air from the air leak. That condition would make it very hard to properly adj.
Tighten your exhaust flanges on both pipes and check your intake manifold is secure at each cylinder and where the carb attaches. Put the rubber caps on the carb discussed earlier. If they are OK try the basic setup again paying close attention to how many turns on the idle mix screw you have so you can tell us what it is if you can't get it adjusted.
Matt300ZXT
Member
I think I may have found a big part of the issue...
I removed this carb (huge pita, don't ever wanna have to do that again) and broke the float bowl loose and removed the idle jet and now I pretty much can't see through it at all. It was cleaned yesterday, could see through it perfectly, and put back in and the bike reassembled and now that I take it out today, it's 99% plugged up. I had a plastic tag holder here (like what holds tags to your clothes at the store) and it was small enough to run through and I finally got it all the way through the idle jet. Apparently there is some crud somewhere in this carburetor that found its way into this jet. The main jet still looks fine, but it's a much bigger hole. I think I'll do like DynoDave said and get one of those fancy inline fuel filters. I'm no bike expert, but intuition tells me if it ain't getting a proper flow of fuel at idle, it's gonna be hard to tune it lol
I removed this carb (huge pita, don't ever wanna have to do that again) and broke the float bowl loose and removed the idle jet and now I pretty much can't see through it at all. It was cleaned yesterday, could see through it perfectly, and put back in and the bike reassembled and now that I take it out today, it's 99% plugged up. I had a plastic tag holder here (like what holds tags to your clothes at the store) and it was small enough to run through and I finally got it all the way through the idle jet. Apparently there is some crud somewhere in this carburetor that found its way into this jet. The main jet still looks fine, but it's a much bigger hole. I think I'll do like DynoDave said and get one of those fancy inline fuel filters. I'm no bike expert, but intuition tells me if it ain't getting a proper flow of fuel at idle, it's gonna be hard to tune it lol
Matt300ZXT
Member
Oh yeah, got it on my desk and already removed one, it was cracked and dry rotted and prolly let a small amount of air in/out. There's a local shop that sells rebuild kits...score.Make sure you replace the two black rubber caps on the top of the carb. They may look ok but dry rot may have got them. Cheap @ auto parts store. If they leak, you will play hell trying to dial it in...and will run like crap when you crack the throttle. Jm
Don’t think of it that way Matt. Your learning how to work on your own Dog. It may be frustrating, but if you just take your time & go over everything very carefully you will get it to exactly what you are looking for. Ask me how I know. In the end you will enjoy doing these things to make your bike the BigDog you want!
Matt300ZXT
Member
Indeed sir, you are a gentleman and a scholar. I just wanna get this thing back together so I can go out and practice more. I was just starting to get better at it and then pow...crud in the jet; a veritable monkey wrench if you will lol
Hopefully this local shop has all the parts in the rebuild kit I need so I can freshen this thing up and soak the hell out of it in carb cleaner....there ain't gonna be no dirt in my carb. Plus, he sells individual jets for a few bucks so I can get a couple sizes of intermediates and test them out and get it juuuuust right. There's a good bit of carbon on these parts from 5400 approximate miles and probably not a single rebuild/cleaning other than the assembly at the factory 20 years ago.
Even though I was cussing at my bike today; the oil filter, getting dirty, having to constantly stop and go get another tool, having to move the ignition/key assembly out of the way to get to the 2 bolts holding the carb on, etc, it IS still easier than working on my 300ZX Twin Turbo lol
francoblay1
The Spaniard
Get the Mixture screw out and check it.... the previous owner of my K9 (or his mechanic), at some stage did tighten it too much and fucked it up...(notice the Groove??)
This thing drove me nuts for awhile when trying to tune it.... installed a new screw and since then its good as gold!!!