Fazer Owners Club - Unofficial
Bikes, Hints'n'Tips => FZS600 Fazer => Topic started by: psyfi_1 on 19 April 2018, 05:40:29 pm
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hi guys just need some advice
my 3-4 cylinder is not getting as hot as 1 and 2
i turn the bike on and let it sit for a few minutes and through some water over the pipes and definitely 3 and 4 are not as hot
can you guys give me a list of things i could do to see what the problem is
and i will start going through them to find out what is wrong cheers
i am quite good with my hands so i will give most things a go cheers
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balance the carbs if it only does it at idle then more than likely that
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certainly sounds like a balancing or idle fuel screw area to be looking at
as davie says start with balancing as idle fuel screws dont tend to change as much
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I bought some new CR8E NGK plugs recently, one pegged out at 8 weeks, then another one or more at 10 weeks.
Noticed at first that pipe #4 wasn't hot, plus the bike was running horribly, but when i changed that plug for an old one it ran okay again for a couple of weeks, then it happened again so put all my old plugs back in and it all ran fine again.
Bought new Iridium plugs on Monday and now everything is as it should be.
Not really ever had plug trouble before in years of riding but that's what mine turned out to be so worth a thought.
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If the bike spends much time outside on the side stand, cylinders 3 and 4 will be most exposed to the elements, sat in water and likely corroded. I'd personally start by checking the plug caps, changing the spark plugs and giving the whole area (and plug caps) a good clean and blast with wd-40.
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http://www.ngk-sparkplugs.jp/english/techinfo/fake/index.html (http://www.ngk-sparkplugs.jp/english/techinfo/fake/index.html)
Most likely fakes. I posted this link a while back on how to spot them.
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okay so i change plugs with some old ones i had left over Not any better also swapped coils 2-3 over no diference whats next to check................................. did check the carb floats bowls and drained loads of crap from bowl 3 but four was okay......
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okay so i change plugs with some old ones i had left over Not any better also swapped coils 2-3 over no diference whats next to check................................. did check the carb floats bowls and drained loads of crap from bowl 3 but four was okay......
There is only one coil that supplies #2 & #3. I assume you mean you switched the plug leads around. If the problem is still there having done that the problem is fuel related.
So you have drained the float bowls but have you taken the carbs out and cleaned the jets?
My money is on a blocked jet now.
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okay so i have tested coils and they are sparking on cylinders 3-4 so do i have to pull the carbs out and clean the jets??/
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Wouldn't hurt to do it mate, having mine stripped and cleaned tomorrow as I was having the same issue on number 4.
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for all you guys getting your carbs stripped, share pictures of what they find in there!!
I've never seen a blocked carb and would be interested to know what it looks like and the sort of thing you find.
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Here is one of my float bowls. :(
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okay so cleaned the carbs i will get them back on tommorow so hopefully i might have all cylinders again....... the float bowls where full of rust...... so we will see if it gets any better......
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Wow, surprised to hear that. Check your fuel filter and air filter! That rust must have got past one of them.
A new fuel filter is only a couple of quid and should stop the rust getting through from you tank.
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if it is 'rust' that has made it through to your float bowls then it is worth the few quid for a new filter as old ones can tear (although rare 'poet')
if they looked like [size=78%]http://www.xjrider.com/viewtopic.php?t=668 (http://www.xjrider.com/viewtopic.php?t=668)[/size]
then it isnt rust but you dont want it in there eitherway
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for all you guys getting your carbs stripped, share pictures of what they find in there!!
I've never seen a blocked carb and would be interested to know what it looks like and the sort of thing you find.
main thing you want to be looking at is your jets and emulsion tubes
have a little piece of wire to hand and make sure all the holes are clear - with small jets i tend to just put them in a tub of carb cleaner while doing everything else then blow through them (a can of compresser air for cleaning computers is great if you dont have a compressor)
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My favourite one is the 'jet' which has a taper inside but no hole. Alot of people (myself included) spend ages trying to unblock that one before eventually realising it isn't a through hole.
I've stripped my carbs twice before. Both times they were spotless inside?! My bike has lived outside for the last 8yrs, usually left sat for 2-3 months at a time. I don't know why they've never been a problem for me?
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If you've got rust in the carbs water is probably getting into the tank. You should clean out the drain tube under the filler cap and make sure it hasn't rusted through. The pipe on the inside of the tank can rust through and let water in. Also rinse out the tank with fresh fuel and put a new fuel filter in.
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okay so any ive put the carb back on but cant seem to ge the throttle cable back on ?? any suggestions...... i have changed fuel filter with new one now air filter doesnt look that bad..... but i will order a new set for it a couple of the jets did have crap in them.... but in the end i think i need to put new seals on everything they are shot basicly.....
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Sorry psyfi... :\ you need to connect the cables and than fit the carbs :'(
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yeh ok shes back together now and running over but the two other cyclinders are still not getting hot do you think i just to put fresh feul and carb cleaner through ??/
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Feel your pain mate.Bloody frustrating this carb business, my number 4 decided not to play ball, cleaned it, unblocked the idle jet and even changed the diaphragm, still not getting hot, oh even clipped HT lead back and changed plugs. If I had hair it would be out by now.
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ive checked the spark ive cleaned the carbs though i didnt put new seals in.... or use carb cleaner i used cotton buds and air blasted but i now i did move crap from the jets ....... and spray down most of the holes
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shall i see if they are really out of balance the carbs i mean??
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I fucked about tried cleaning my low mile originals 3 times with they've only done 10,000 miles !
Tried 4 other sets until I got some that worked perfectly,I found out its not just jets there's a few tiny orafaces inside that clog too.
The jets also get yellow/green gunge inside them you cannot easily clean or even get to,the best option is to buy new emulsion tubes, jets etc & replace the rubber parts too.
My low mileage set needs about £80 or so spent to make them good,we've got the EU & the shitty petrol they sell to thank !
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I fucked about tried cleaning my low mile originals 3 times with they've only done 10,000 miles !
Tried 4 other sets until I got some that worked perfectly,I found out its not just jets there's a few tiny orafaces inside that clog too.
The jets also get yellow/green gunge inside them you cannot easily clean or even get to,the best option is to buy new emulsion tubes, jets etc & replace the rubber parts too.
My low mileage set needs about £80 or so spent to make them good,we've got the EU & the shitty petrol they sell to thank !
Those tiny orifices are the transfer ports. If you look at the carbs on the airbox side you see two air jets. The one on the left is the pilot air jet
(https://i.ebayimg.com/00/s/NTc3WDEwMjQ=/z/EYsAAOSw6btXTWet/$_86.JPG)
At idle air is drawn through that jet down a small orifice and it goes into the holes in the side of the pilot jet and out the narrow end of the jet.
(https://img.staticbg.com/thumb/water/upload/2015/05/SKU222434%20(3).jpg)
That draws fuel up from the bowl at the slotted end of the pilot jet and up through the center of the jet and the air fuel mixture goes down another orifice and comes out of the small holes on the engine side of the butterfly valve called transfer ports. The transfer port orifice is joined to the the mixture screw orifice so the air fuel mixture also comes out at the mixture screw hole. Turning the screw in blocks the hole and turning it out lets more fuel through.
(http://prepforshtf.com/wp-content/uploads/2013/03/Transfer_Ports.jpg)
That's how the idle circuit works and all of the passages have to be clear not just the jets.
There's a good diagram of what I'm saying. The left side is the airbox side
(https://i2.wp.com/cdn1.share.slickpic.com/u/TheXscafe/CarbMikuni/org/06%20CV_Cutaway/web.jpg)
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i was pretty sure i had cleaned them....... i will wait for carb cleaner to some and do it again with a guitar string and see if that does anything....
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I blow air though & make sure all the carbs sound the same though each oraface,if not it's not clean enough !
The problem I had was a flat spot about 1.5-2k so it's just where the idle jet crosses over to the main jet circuit,the main jet emulsion tube is also prone to the green/yellow coating inside.
You can buy the exact new parts for these carbs,because their commonly used in other models.
I did read that paint thinners can soften the gunge but I've never tried it myself.
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I edited that last post to make it a bit clearer.
I blow air though & make sure all the carbs sound the same though each oraface,if not it's not clean enough !
The problem I had was a flat spot about 1.5-2k so it's just where the idle jet crosses over to the main jet circuit,the main jet emulsion tube is also prone to the green/yellow coating inside.
You can buy the exact new parts for these carbs,because their commonly used in other models.
I did read that paint thinners can soften the gunge but I've never tried it myself.
It's more about throttle position than rpm. If the flat spot is at 1.5-2k you'd only have the throttle open a tiny bit so I'd estimate 90% or more of your air/fuel mix would be from the pilot circuit. If you're having a flat spot there and you think it's fuel related you should clear out the pilot air jet, pilot fuel jet, mixture screw and very importantly the transfer ports because that's where the fuel comes out. If the transfer ports are blocked cleaning out the jets isn't going to solve the problem. The transfer ports are so small that carb cleaner or an ultrasonic cleaner is the best way to dissolve the crap and old varnished petrol. After everything is clean adjusting the mixture screws and balancing the carbs would also help but everything has to be clean first
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Electrical faults can create flat spots with throttle position. As the mixture resistance changes you can find opening the throttle with a weak spark will make it misfire, back off on the throttle and the engine picks up.
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Electrical faults can create flat spots with throttle position. As the mixture resistance changes you can find opening the throttle with a weak spark will make it misfire, back off on the throttle and the engine picks up.
Yea I've experienced that where a cylinder was dropping out because of water around the spark plug caps causing arcing to happen but only at low revs. Then as you're saying the mixture resistance must have lowered as you opened the throttle because the arcing stopped as the revs went up and the bike ran normally.
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right the top of cylinder 3-4 are hotter now defintatley but they still dont seam to be as hot as the other two..... i will put balance on them later and see whats going on...... if the balance is out will it give a diferent tempreture reading??
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right the top of cylinder 3-4 are hotter now defintatley but they still dont seam to be as hot as the other two..... i will put balance on them later and see whats going on...... if the balance is out will it give a diferent tempreture reading??
It can do. But how is the bike running is the important question I don't think you mentioned that. What is it doing? Is it lumpy at idle? Is it mis firing when you open the throttle? Does it feel down on power when you're riding? If you've got a mis or a cylinder that isn't contributing you can use the water on the exhaust trick to show which cylinder is the problem cylinder. If the bike is running ok and there's no mis and there's still a difference in exhaust temperatures it can be caused by a rich or lean mixture. The leaner the mixture is the hotter it burns and the richer the mixture is the cooler it burns so if you do the water on the exhaust trick and it can give you an indication of rich vs lean on each cylinder, also if you take out the spark plugs and read them. Black and sooty is rich, white is lean, wet is no spark, and you combine that with the exhaust temp you can get an idea of the problem.
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okay idling is fine is happy at idleing when when warm okay just after a few mins needles a little jumpy though okay riding is pretty smooth until you give it some then the engine shakes she looses power then if i let of the revs a bit she settles and i can pull back to higher reves but cant blam the throttle basily....
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It could be fuel/air related or it could be spark related (ask Red98 about his stutter :lol ). You'll have to rule things out with trail and error. But from your description it sounds like it runs ok until you open the throttle suddenly and a lot then it stutters and stumbles. The water on the exhaust is suggesting that 3 and 4 are the cylinders stumbling so it could be a problem specific to them. Did you check the diaphragm rubbers for holes when you had the carbs apart? If there's holes in the diaphragms the slides won't lift so your main jet won't come on when you wack the throttle open. That could be the problem. A blocked air filter could be the problem causing a restriction in the air flow. It could be blocked jets on 3 and 4 carb. It could be a spark related problem that only happens up the rev range.
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okay i have balanced the carbs now the pipes are the same now and all are hot........ fuck yes when i get her back on the reoad legaly i will give her a test run and see what happens but for now just front rear brakes to do and fenders to paint also some touch up on the front fairing bolts cause there rusty lol