carlo Posted August 13, 2013 Share Posted August 13, 2013 Can anyone help, I have a virago 125 year 2000 that hassat in a garae for 12 years with only 869 on the clock.. The owner had a prob, ith only running on 1 cylinder so took it to the garage, they changed the carb, the pump and all the hoses, but it was still the same. It will start but only on full choke and then if you rev it it will cut out straight away, will not start with no choke. Have replaced the petrol and battery, and there is no knocking etc, from the engine or smoke, has a good spark on both plugs and comp, is ok on both cylinders. Any ideas anyone Thanks Link to comment Share on other sites More sharing options...
carlo Posted August 13, 2013 Author Share Posted August 13, 2013 Can anyone help, I have a virago 125 year 2000 that hassat in a garae for 12 years with only 869 on the clock.. The owner had a prob, ith only running on 1 cylinder so took it to the garage, they changed the carb, the pump and all the hoses, but it was still the same. It will start but only on full choke and then if you rev it it will cut out straight away, will not start with no choke. Have replaced the petrol and battery, and there is no knocking etc, from the engine or smoke, has a good spark on both plugs and comp, is ok on both cylinders. Any ideas anyone Thanks forgot to add it has a new air filter as well, also does the same thing with the air filter removed. Theres no prob, with the clutch or side stand switch either. Will engage gear when ticking over on the choke (won't start or tick over without the choke out) and will pull away when clutch let out, but without revs as it will cut out if you just twist the throttle a tiny bit. I'm thinking this has to be carb, prob, even though they changed the carb, ay ideas anyone! Link to comment Share on other sites More sharing options...
neversaydie Posted August 13, 2013 Share Posted August 13, 2013 Your description does sound like its a fuelling problem. You say they changed the carb, what actually did they fit, a new one/new jets/second hand. You need to establish facts here so to have a base from which to work Check the petcock is operating correctly, does it rely on vac pressure to operate? Link to comment Share on other sites More sharing options...
Moderator Airhead Posted August 13, 2013 Moderator Share Posted August 13, 2013 yeah it does sound like a carb or fuel supply problem Link to comment Share on other sites More sharing options...
dt502001 Posted August 13, 2013 Share Posted August 13, 2013 No mention of spark on the cylinder that's inop? OOPS just re read . so what about if you put a we bit of gas directly in the cylinder will it warm the exhaust pipe Link to comment Share on other sites More sharing options...
carlo Posted August 14, 2013 Author Share Posted August 14, 2013 Your description does sound like its a fuelling problem. You say they changed the carb, what actually did they fit, a new one/new jets/second hand. You need to establish facts here so to have a base from which to work Check the petcock is operating correctly, does it rely on vac pressure to operate? Hi Not sure if it was a new one or not, it has sat for 10 years as he could not get it going.The pet cock is fine and the fuel pump that is pumping the fuel to the carb with no prob, I lso drined the tank and put new fuel in. I have taken the carb off and cleaned it all and the jets twice now, the only diff, is that it will run now on tickover without having the choke on full but you can't rev it, it will cut out. When ticking over and I adjust the pilot screw the revs will increase, but still can't rev it. Every time I strip it the jets are clear, not blocked, thinking now that it's maybe blocked somewhere else other than the jets. Will prob, order a main and pilot jet and se if tha work, maybe jet up with a 17.5 and 145, if that does not work I guess it will be a new carb, Thanks for the suggestions Link to comment Share on other sites More sharing options...
carlo Posted August 14, 2013 Author Share Posted August 14, 2013 No mention of spark on the cylinder that's inop? OOPS just re read . so what about if you put a we bit of gas directly in the cylinder will it warm the exhaust pipe Hi It's def, running on 2 cylinders both cylinders red hot Link to comment Share on other sites More sharing options...
Moderator Airhead Posted August 14, 2013 Moderator Share Posted August 14, 2013 get your carb ultrasonic cleaned Link to comment Share on other sites More sharing options...
carlo Posted August 14, 2013 Author Share Posted August 14, 2013 get your carb ultrasonic cleaned hi do you mean the whole carb or just te jets, don't know of anywhere where they clean a whole carb, and as I said the jets are not blocked when I strip it. What do you think the best stuff to use to soak the carb to clean it, I mean the whole carb not just the jets thanks Link to comment Share on other sites More sharing options...
Moderator Airhead Posted August 14, 2013 Moderator Share Posted August 14, 2013 I have heard of people simmering them in a saucepan of water with lemon juice, I have no experience of this though, if you go down this route you should blow it all out with compressed air afterwards...and remove all rubber components first....Dont put the slide and diaphragm in there it wont need cleaning and you cant remove the diaphragm Either that or take it for ultrasonic cleaning somewhere Link to comment Share on other sites More sharing options...
carlo Posted August 14, 2013 Author Share Posted August 14, 2013 I have heard of people simmering them in a saucepan of water with lemon juice, I have no experience of this though, if you go down this route you should blow it all out with compressed air afterwards...and remove all rubber components first....Dont put the slide and diaphragm in there it wont need cleaning and you cant remove the diaphragm Either that or take it for ultrasonic cleaning somewhere wow lemon! to be honest I will try anything now. Will strip it again tomorrow, I really think this is idle jet/pilot jet prob, the hole is really small, smaller than any other carb I have seen, think I will order a largr size, book says the pilot is 17.5 and main 135, so maybe up it 2.5 or 5.0 not sure if I should up the main jet as wellor by how much, any ideas? Thanks Link to comment Share on other sites More sharing options...
Moderator Airhead Posted August 14, 2013 Moderator Share Posted August 14, 2013 Theres no reason to 'up' any of the jets, it's more likely crud in one of the little passageways...buy an aerosol carb cleaner spray and with the straw...spray through these passageways Link to comment Share on other sites More sharing options...
carlo Posted August 14, 2013 Author Share Posted August 14, 2013 Theres no reason to 'up' any of the jets, it's more likely crud in one of the little passageways...buy an aerosol carb cleaner spray and with the straw...spray through these passageways been there and done that twice, also blown out carb twice with comp, air. I'm only thinking of this as I seen something on youtube with a guy that had the same prob, and he upped the pilot only and it cured the prob, this was after him doing all the usual stuff, ie stripping carb, cleaning jets, jets not being blocked etc etc, I have the old carb, that is in bits that came with the bike and the pilot is 17.5 and looks ok, so will try changing that on it's own. I have noticed that the old carb is diff, to the new carb, in that the choke cable does not connect to the, wheel next to where the throttle cable attaches as it does on the old carb, but it screws into the carb, on one end is normal nipple that connects to the choke lever the other end has a bolt and thread with a spring and kind of plundger, this screws into the side of the carb, never seen this set up before. Link to comment Share on other sites More sharing options...
gizmo666 Posted August 15, 2013 Share Posted August 15, 2013 check the carb diaphrams are not pitted Link to comment Share on other sites More sharing options...
carlo Posted August 15, 2013 Author Share Posted August 15, 2013 check the carb diaphrams are not pitted nope it is fine, it's like new as the prev, owner had a diff, carb put on it and a fuel pump, just the same as the manifold to engine from carb, and air cleaner like new. Stripped it again today and cleaned every hole I could find in it, all airways clear, jets clear, and guess what, yep it is exactly the same, will tick over but as soon as you try and rev it it will cut out, doing my head in now, really tempted to just buy a new carb, even if it is expensive, I would if I knew it was def, the carb, but it looks fine, don't understand it, never had this much trouble with a carbs in my life, have stripped and repaired a few, inc, 4 carb, blocks, at my wits end now AHHHHHHH Has anyone had this prob, before where whatever they did it would not run and as a last resort they put a new carb on and all was fine? Link to comment Share on other sites More sharing options...
Moderator Airhead Posted August 15, 2013 Moderator Share Posted August 15, 2013 have you examined the rubber boots between the carb and the cylinders and carb to airbox...particularly looking for perishing / splitting ? Link to comment Share on other sites More sharing options...
carlo Posted August 15, 2013 Author Share Posted August 15, 2013 have you examined the rubber boots between the carb and the cylinders and carb to airbox...particularly looking for perishing / splitting ? Hi The manifold Y connection is new, also the boot to the airbox, have tried running it with theairbox off and the overflow from crb, disconected, but still the same, ticks over but won'r rev, think I m going to buy a new carb, don't know what else o try now. Link to comment Share on other sites More sharing options...
Moderator Airhead Posted August 15, 2013 Moderator Share Posted August 15, 2013 perhaps it may not be the carb you've done so much cleaning to it ? then you'll have wasted money! tell us about the fuel feed to the carb...is it pumped or gravity did you disconnect it and witness a good flowrate of fuel (taking obvious care here) i'm thinking a bike that sat 12 years may well have blocked fuel filter screens? Common places for filter screens are Inside the fuel tank where the petrol tap feed tube enters the tank in a bowl on the petrol tap inlet to fuel pump? Hey I found this on my TTR600 actually inside the carburettor on the inlet to the float valve seat so a strong fuel flow wouldnt have shown this one up! Link to comment Share on other sites More sharing options...
carlo Posted August 15, 2013 Author Share Posted August 15, 2013 perhaps it may not be the carb you've done so much cleaning to it ? then you'll have wasted money! tell us about the fuel feed to the carb...is it pumped or gravity did you disconnect it and witness a good flowrate of fuel (taking obvious care here) i'm thinking a bike that sat 12 years may well have blocked fuel filter screens? Common places for filter screens are Inside the fuel tank where the petrol tap feed tube enters the tank in a bowl on the petrol tap inlet to fuel pump? Hey I found this on my TTR600 actually inside the carburettor on the inlet to the float valve seat so a strong fuel flow wouldnt have shown this one up! Hi Does not have these screens on it, it has a pump to the carb, seems to be plenty of fuel getting to the carb, but I will look at the flow tomorrow, but as the prev, owner had the pump repaced and the carb, I doubt it is that. The garage gave up trying to get it going in the end, after changing the carb, (but the carb does not look brand new outside but all new inside) also changed the fuel pump, air filter, engine boot to carb, boot from carb, to air filter, throttle cable, choke cable, all new fuel hoses. If it's not the carb, or the pump I'm stumped, can't see it wouldbe electrical as have a good spark, both cylinders fire, both get hot, and it starts fine, just won't rev, Thanks Link to comment Share on other sites More sharing options...
carlo Posted August 16, 2013 Author Share Posted August 16, 2013 perhaps it may not be the carb you've done so much cleaning to it ? then you'll have wasted money! tell us about the fuel feed to the carb...is it pumped or gravity did you disconnect it and witness a good flowrate of fuel (taking obvious care here) i'm thinking a bike that sat 12 years may well have blocked fuel filter screens? Common places for filter screens are Inside the fuel tank where the petrol tap feed tube enters the tank in a bowl on the petrol tap inlet to fuel pump? Hey I found this on my TTR600 actually inside the carburettor on the inlet to the float valve seat so a strong fuel flow wouldnt have shown this one up! UPDATE after removing the aircleaner I have just tried blocking the air cleaner intake hole with my hand whilst it is ticking over and then reving the bike as I remove my hand and it revs up to the max for 5 seconds then drops back to the normal tickover, did this about a dozen times but if I don't have my hand over it and then removing it as I rev it still reverts to not being able to rev, just cuts out when you try and rev it. Now this tells me, I may be wrong, it is either a leak at the carb intake or carb manifold or blocked carb, I had it ticking over and sprayed carb cleaner at the carb intake and carb manifold but no increase in rev, so would think thats not the prob, I think it must still be a blocked carb somewhere, can't tink of anything else, any ideas ? Thanks Link to comment Share on other sites More sharing options...
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