Fuel system and carb overhaul '99 curvy Qs

After standing for far too many months, my '99 curvy SV is struggling to get going again. A number of problems have raised their head; first the fuel tap vacuum hose was cracked, then the fuel seemed to have 'gone off', and after finally getting it running, it would only idle, any revs would kill it. After checking the ignition circuit and spark plugs, it looks like fuel starvation, and the bike is due a carb overhaul anyway. So I've taken the carbs off for a good clean. I then thought about the problem, and decided to have a look at the fuel pump as well, which is again vacuum-powered. Vacuum hose was okay, so I ended up taking it apart, and there seemed to be a lot of separated out fuel (may have been water) in one half of the pump. Unfortunately I have ripped one of the gaskets taking it apart. So, two questions for you good people:
1. Carb overhaul kits (gaskets etc)? Found this one on wemoto, which I guess I need two of: http://www.wemoto.com/bikes/Suzuki/S...oat_Valve_Kit/
2. I can only find complete fuel pumps, and they are quite expensive. Is there a gasket kit for it? It's the version on this microfiche: http://www.ronayers.com/Fiche/TypeID...PUMP_FUEL_PUMP

Well, I have rebuilt the fuel pump with the original gaskets as I can't seem to find a kit, and it seems to be working okay - a good squirt of petrol comes flying out when I apply some suction to the vacuum pipe. I'll start stripping the carbs this evening, though now I reckon that it's water/separated fuel in the float bowls that is the main problem. I'll see if I need the gasket kits for them as I take them apart. Any advice welcome!

I have rebuilt the carbs over the last couple of evenings, first using Gunk to degrease them, then a good clean off and scrub in soapy water, disassembly and then another degreasing for the main parts. Then a good clean of all internal parts, fuel and air galleries with Carburetor cleaner. Finally put them all together after a quick blast through the fuel and air galleries with can of compressed air.
There are quite a lot of cross head bolts on the carbs. It's very easy to chew these up, especially when they get a bit corroded. I prepped most of them with a squirt of WD40, and made sure that the head of each screw was clear of dirt so a correct size Phillips screwdriver blade fits as snugly as possible. I then used an electric screwdriver (actually a torque-adjustable cordless drill) to undo the screws, which I find much more reliable than using hand tools. I think this is because it can deliver lots of torque instantaneously, which you can't do as well with a screwdriver. I separated the carbs from the metal carrier that connects them, which probably wasn't required, but meant I could clean them properly. I managed to knacker one screw on the carrier, which for some reason I tried to undo with a screwdriver. I had to cut a slot in the screw with a hacksaw, then it came undone easily with the electric screwdriver. I haven't got any spares, so it'll have to be refitted. Only other problem is that the pilot adjuster on one of the carbs (the front one) is properly seized. Oh well, never noticed a problem, guess it stays as it is. I reused all gaskets, they all seemed in good condition.
Hopefully I will get to refit the carbs tomorrow. Here's a picture of what they look like - nice and shiny!



I'll probably check the valve clearances while I'm about it as there's plenty of space to do it with the carbs off.

Looking nice!

I need to do this, just not got the time to dedicate to anything worth doing on the bike right now. Sucks.

Hi, thanks for the reply, I was wondering if anyone around here even had an SV anymore! Or maybe no one really tackles this sort of job themselves.
It's not too difficult a job, but it is time and space consuming. I checked the valve clearances (all within spec) and put it all back together this evening, and finally nervously thumbed the starter... It took about ten seconds for the fuel to run back through the system, but now everything is peachy. Twisting the throttle actually makes the engine go faster rather than stop! It seems a touch smoother picking up from idle, but it might be my imagination. I've got a few bits and pieces to do - it needs a new inline fuel filter and a new vacuum hose between carb and fuel tap. I think I could have got away with draining the fuel pump and carbs, but at least I know the job has been done properly, and won't need to be done again for quite a while.
Just realised it has MOT, tax and insurance, so hopefully I'll be out on it at the weekend if this nice weather holds. Roll on summer...

These look really good. I did mine a while ago and I know what you mean about the bolts getting chewed up, some of them feel really cheap and nasty. What were your jet needles like? Mine (on a '00 bike) were really gunked up.

The carbs were very clean on the inside. There was a tiny bit of crud on the pilot jet (at least, the one I could remove), but the other jets and needles were really clean, no varnishing in the float bowl. Maybe the carbs have been apart before, but there were no marks on the screws. There are now! My bike has an inline fuel filter which I'm about to replace, and there's quite a lot of rubbish in that, mostly .5 to 3mm size particles that look like rust/crud from the tank. There is also a fine screen on the float valve, and that had a few smaller bits on it. So perhaps the double filter has kept the worst at bay - I was surprised how clean it was, despite running it on Tescos 95 RON, with occasional fill-ups of Shell/BP 97/98 RON when I was feeling rich! (Not any more!)
I get the feeling that petrol is having more additives put in it, kind of like cutting cocaine with talcum powder (I presume!). Petrol just doesn't seem to have the longevity it used to. I think my bike's problem was down to separated fuel and possibly water in the tank making its way into the fuel pump and carbs, either from condensation or some other unknown source.

Is it easy to ensure the carbs are balanced and that the pots will be performing the same, I have just stripped the engine down and the front pot appears to be running alot hotter that the rear, this could be due to incorrect setting of the fuel mixture or because of the valve clearances. The valves I am happy doing, I am not so sure about the carbs though.

[yorkie_chris]

Yeah but a set of gauges is required

Originally Posted by garrystr

Is it easy to ensure the carbs are balanced and that the pots will be performing the same, I have just stripped the engine down and the front pot appears to be running alot hotter that the rear, this could be due to incorrect setting of the fuel mixture or because of the valve clearances. The valves I am happy doing, I am not so sure about the carbs though.

Yes, the carbs are reasonably easy to strip, clean and re assemble, but there are a lot of steps to it. Just take your time, clean them thoroughly before taking them apart, and work on a clean surface - kitchen table if you can get away with it! Take photos as you disassemble with a digital camera or phone, it will help get all the tubes and wires back in the right place when you reassemble. Don't rush taking it apart with poor quality tools; as mentioned earlier, some of these nuts and bolts are quite poor quality, and have been on the bike exposed to the elements for a long time. Do one carb at a time to avoid mixing up parts. So long as you don't move any of the adjusters, or make a note of where each one is set (eg "two turns out from full in" etc) you should generally be okay without rebalancing with a vacuum gauge, but it is desirable to do this as everything is accessible.
Valve clearance is again relatively straightforward, and can be done without taking the carbs off, and worth doing for the symptoms you describe before taking the carbs apart. Actually changing the shims is trickier, but if valves clearance is okay, it is one problem ruled out. Again, take your time, try not to rip the rocker cover gasket, they are expensive to replace. I simply followed my Haynes manual through both operations, and it turned out okay!