Kelum Posted August 22, 2013 Posted August 22, 2013 Hi guys.... Just to wrap up, my xv125 engine ceased as the oil pump wheel was worn out and the oil wasnt circulating inside...Then I replaced piston rods, piston rings and wheels with genuine Yamaha parts. Replaced manifold joint and it was not fitting well. So placed some spacers with gasket material cut accordingly between engine head and manifold joint. Bike started well after this but after sometime started to just crank like fuel starvation. I bought another fitting manifold joint and replaced non-fitting with it. Tried to start...Bike would start for sometime at first crank, however, it would not start later... I thought my carb had issues, cleaned it with carb cleaner, checked the needles, diaphragms,,, all were ok, float was doing its job right... Starting problem went on, I thought carb was faulty...bought a good condition second hand carb at 40USD....Installed it and the same problem still exists... According to yesterday's attempt, when u push the bike at first gear, bike tries to start but wouldnt hold on...when cranking it sometimes start...not always...when starts you can ride it, it revs better.. When it stops starting, if you let her stay like that for say 10miuntes at PRI and crank, for few secs the engine struggles to run....but wont hold on, sometimes she starts ok...Its like when you keep the bike stand still, by some means some petrol finds its way to inlet manifold and when I fire it burns for few secs...but it wouldnt happen continuously... membrane has no cracks, membrane piston is ok...float is hanging freely...its needle too ok... Two longer jets in float bowl dips ok in petrol at float's closed position...what does the shorter, smaller left side on do, it doesnt seem to dip in petrol...what does that jet do? To me however, this seems to be a petrol starvation issue...cos for the second time the mech confirmed timing and tappets all ok...
Kelum Posted August 22, 2013 Author Posted August 22, 2013 Can someone tell me about the function of the 3 jets inside float bowl? The two bigger ones dipping in petrol it seems...the petrol level inside the bowl could be estimated by the upper lift amount of the floater right? at this level however, the smaller jet at left does not seem to be able to suck in petrol...is that the one causing issue? What does this jet do? As I have marked in the pic above, if I take the lower edge of floater as the petrol level, when floater shuts the petrol flow into carb bowl, this little jet at left does not dip in the petrol, so what is the function of it?
dt502001 Posted August 24, 2013 Posted August 24, 2013 That is the pilot jet it's the smallest and the passage runs infront of the slide eng side it will pick up fuel from the bowl because of the vaccume created by the motor. remove the pilot jet and run a very small wire up the hole you will see it opens at the eng side of the slide,this hole and jet are also contrloed by the tapered screw that varries the amount of air alowed to flow that also enters the same passage. This circut of the carb controls idle fuel flow after the choke has been turned off.And this is why the float height must be set exact height to low of fuel in the bowl and it can't pick up enough fuel to high and it gets too much both will cause starting and idle problems. The other jets control fuel flow from 1/8 throttle opening to full open. The choke circut basicaly alows the pilot jet to suck more fuel in by 1 of 2 means either block air or a seperat circut to alow more fuel in. Sorry I cant help more but we never got them bike's here and I have never worked on one but,carbs are carbs they all work basicaly the same. Maybe one of the other members could help with the float height and how it's to be set,some need to be done with the carb held on a angle of 15 degerees other held flat.When I dont know I hold the carb with the float open and slowly turn it so the float is closing slowly as soon as the float has closed the fuel inlet valve the float arms shold be even with the body of the carb where the bowl fits on,this will give you a good base setting. But all the passeges in the carb must be 100% clean soak the carb in deisle for a couple of days with the rubber bits removed then blow clean with compressed air. Ok the rest of you guys here someone must have a spec sheet ,or know someone with info about the 125 vigges carb settings,he's been fighting this for months how about lending a hand to a fellow biker in need.
Kelum Posted August 25, 2013 Author Posted August 25, 2013 That is the pilot jet it's the smallest and the passage runs infront of the slide eng side it will pick up fuel from the bowl because of the vaccume created by the motor. remove the pilot jet and run a very small wire up the hole you will see it opens at the eng side of the slide,this hole and jet are also contrloed by the tapered screw that varries the amount of air alowed to flow that also enters the same passage. This circut of the carb controls idle fuel flow after the choke has been turned off.And this is why the float height must be set exact height to low of fuel in the bowl and it can't pick up enough fuel to high and it gets too much both will cause starting and idle problems. The other jets control fuel flow from 1/8 throttle opening to full open. The choke circut basicaly alows the pilot jet to suck more fuel in by 1 of 2 means either block air or a seperat circut to alow more fuel in. Sorry I cant help more but we never got them bike's here and I have never worked on one but,carbs are carbs they all work basicaly the same. Maybe one of the other members could help with the float height and how it's to be set,some need to be done with the carb held on a angle of 15 degerees other held flat.When I dont know I hold the carb with the float open and slowly turn it so the float is closing slowly as soon as the float has closed the fuel inlet valve the float arms shold be even with the body of the carb where the bowl fits on,this will give you a good base setting. But all the passeges in the carb must be 100% clean soak the carb in deisle for a couple of days with the rubber bits removed then blow clean with compressed air. Ok the rest of you guys here someone must have a spec sheet ,or know someone with info about the 125 vigges carb settings,he's been fighting this for months how about lending a hand to a fellow biker in need. Thanks a lot DT....my point is that I have replaced the whole carb and the bike still having issues...at least one carb has to do the thing right...now I feel like some tappet issue...but still why does the bike start on and off...? When you leave the bike for say 15 minutes and crank, it would try to start...but wont hold on, the second time you crank, it just cranks...no starting attempt at all...so this suggests me that leaving it for some time kinda seeps petrol in slowly...I dont know I feel it that way...I dont think anyone has played with floaters...no sign of bending etc...so I think all are at original settings...to be exact DT, the bike has been down for more than 1 year now...
dt502001 Posted August 25, 2013 Posted August 25, 2013 Ok klume lets go with some basic ways of getting it running then,and start ruleing out the possibles. 1st put some fuel right in the cylinder's about a tea spon full,then put the spark plugs back in and try to start right away. If it starts and run then we need to be looking at the carb more closely,just because they are different dosen't mean they are right eps because the one you bought was shipped,,which means it's been thrown about without care.Ever met a postmen who give's a rats ass about the parcels he's handeling NOPE THEY BREAK AS MUCH AS get delivered without breakage 2nd if the first works get back to me and I will try to help you set the carb up
Kelum Posted August 25, 2013 Author Posted August 25, 2013 Ok klume lets go with some basic ways of getting it running then,and start ruleing out the possibles. 1st put some fuel right in the cylinder's about a tea spon full,then put the spark plugs back in and try to start right away. If it starts and run then we need to be looking at the carb more closely,just because they are different dosen't mean they are right eps because the one you bought was shipped,,which means it's been thrown about without care.Ever met a postmen who give's a rats ass about the parcels he's handeling NOPE THEY BREAK AS MUCH AS get delivered without breakage 2nd if the first works get back to me and I will try to help you set the carb up Ok....but here in this particular place they buy bikes even if they are working and disassemble and sell parts at a lower price but the ultimate of all parts will exceed the price they bought bike at...Its a business they are doing... Last time as you suggested, I poured a teaspoonful of petrol from top of the carb and bike started right away..So I thought carb was faulty....thats why I bought another...this replace seems to be better than the original... Bike is 42km away at my mom's place, am at wife's place now..but going there once a week...pls log in everyday or I'll PM you when going there so you could stay in touch..I must clean the new carb very well...I didnt do tht, just installed...lets see that tooo...
dt502001 Posted August 25, 2013 Posted August 25, 2013 Klume I'm here every day sometime 2 or 3 times I don't sleep well. Breaking bike's apart for parts goes on everywhere not just wher you live,but not alway's are the parts still in good working order. Ok so pouring gas in get's it running then you have 1 of 2 problems the gas is not getting to the carb fast enough,,or the carb is not set up right/dirty.So remove the hose to the carb and make sure you have a very good flow of gas to the carb. If you have agood flow then your carb is at fault.
Kelum Posted August 25, 2013 Author Posted August 25, 2013 Klume I'm here every day sometime 2 or 3 times I don't sleep well. Breaking bike's apart for parts goes on everywhere not just wher you live,but not alway's are the parts still in good working order. Ok so pouring gas in get's it running then you have 1 of 2 problems the gas is not getting to the carb fast enough,,or the carb is not set up right/dirty.So remove the hose to the carb and make sure you have a very good flow of gas to the carb. If you have agood flow then your carb is at fault. Yes I agree regarding bike disassembles... I always kept the bike at PRI...I didnt see an issue regarding flow, but must check if rusty debris in tank blocking the required flow...Is it ok to add petrol into tank, shake well and remove, will it flush the tank? I blew air through carb gas feed line and tested floater valve open, closed positions rotating the carb...no problem with close/open.. I think what you say has a point.....lets see....thanks for the time...
dt502001 Posted August 25, 2013 Posted August 25, 2013 Ok rust in tank drain fuel out,get a bunch of screws and put them in the tank fill with a bit of water a shake the hell out of it in every direction up down side to side ect,remove the petcock and flush the tank untill no more rust comes out.Then get a sealer kit and reseal the tank to stop the rust from comming back andd causing problems again. Now get a bottle and make a way of hanging it from the handle bar and a longer hose to feed the carb,think like when people are in the hospital and have a iv drip,you know what I mean? you have seen people walking around with a pole on wheels a bag with medicen in and a hose to thier arm,and lets feed the carb gas that way.If the bike then runs you have found the problem either the petcock is pluged or the rubber washer inside has blocked the passage. Just thinking don't you have 2 of these bikes?
Kelum Posted August 25, 2013 Author Posted August 25, 2013 Ok rust in tank drain fuel out,get a bunch of screws and put them in the tank fill with a bit of water a shake the hell out of it in every direction up down side to side ect,remove the petcock and flush the tank untill no more rust comes out.Then get a sealer kit and reseal the tank to stop the rust from comming back andd causing problems again. Now get a bottle and make a way of hanging it from the handle bar and a longer hose to feed the carb,think like when people are in the hospital and have a iv drip,you know what I mean? you have seen people walking around with a pole on wheels a bag with medicen in and a hose to thier arm,and lets feed the carb gas that way.If the bike then runs you have found the problem either the petcock is pluged or the rubber washer inside has blocked the passage. Just thinking don't you have 2 of these bikes? Yes, must do that....will do the tank that way....and saline system... Yep I have two bikes...one am riding has a very tough bus hose fitted between carb top and bike frame to allow air from air filter come in...I dont wanna toy with it as it was very difficult to fit in even for the mech...Otherwise I would have tried that bike's carb with this one already....Dont wanna toy with it mate, I mean it...dont wanna let her fall and stay home once again..
Kelum Posted September 7, 2013 Author Posted September 7, 2013 I went through some low compression symptoms...as I feel everything works fine... Last week bike was startng and today when I cranked it didnt... I forgot to mention the rough uncontrollable kinda start..and the very strong oil burn or unburnt oil smell comming from under your seat where there is an exhaust opening next to rear cyllinder head..its so strong that when you rev the engine you feel very dizzy...engine has some strange noise and roughness when it runs...this is not the case with my other bike...and I really feel the bike is trying to start when I crank...... When the mech was going to install new rings, it wasnt possible as they made piston's up and down movement very difficult, so his idea was to use the same old rings with 1 or two new combined...Bike doesnt start due to low compression...it starts sometimes though...what do you think?
Kelum Posted September 8, 2013 Author Posted September 8, 2013 am Now whats up get the bike running? I went through some low compression symptoms...as I feel everything works fine... Last week bike was startng and today when I cranked it didnt... I forgot to mention the rough uncontrollable kinda start..and the very strong oil burn or unburnt oil smell comming from under your seat where there is an exhaust opening next to rear cyllinder head..its so strong that when you rev the engine you feel very dizzy...engine has some strange noise and roughness when it runs...this is not the case with my other bike...and I really feel the bike is trying to start when I crank...... When the mech was going to install new rings, it wasnt possible as they made piston's up and down movement very difficult, so his idea was to use the same old rings with 1 or two new combined...Bike doesnt start due to low compression...it starts sometimes though...what do you think?
dt502001 Posted September 8, 2013 Posted September 8, 2013 not sure as i can't hear it,does it sound like the top or bottom is noisey? The mechanic is not verry good ,he should have filed the end gap and then they would have fit. So fix the compression issues first as it sounds as if the bottom ring that control oil from getting to the top of the piston are shot. fix the exhaust leak
Kelum Posted September 8, 2013 Author Posted September 8, 2013 not sure as i can't hear it,does it sound like the top or bottom is noisey? The mechanic is not verry good ,he should have filed the end gap and then they would have fit. So fix the compression issues first as it sounds as if the bottom ring that control oil from getting to the top of the piston are shot. fix the exhaust leak Actually I bought two new ring sets...but when mech tried to install them, he figured out that the piston was not moving up and down with required amount of friction..he said with new piston rings installed, it was too tight...so he decided to leave a one or two rings as it is, which means he let few old rings to stay there...I think this is the reason for entire thing...I dont think the strange fut fut coming from top..not tappets...in virago xv125, this exhaust opening is the original setup...you cannot fix it...the barrel left open...but in my other bike I dont get unburnt fuel/oil smell even though the same place is open..with everything checked so far...this seem to be the issue..if it were a carb issue...it wouldnt have come this far...probably one of many fixes I tried so far would have solved it...
dt502001 Posted September 8, 2013 Posted September 8, 2013 Kluem when you put new rings in they have to be fit to the size of the bore,you place them in the cylinder and check the gap with a feeler gauge if no gap the you take a file and remove mettal untill you have the correct gap,then fit to the piston and install.Only putting in a few is a waist of time. Was the noise there before the mechanic mess with it?
Kelum Posted September 9, 2013 Author Posted September 9, 2013 Kluem when you put new rings in they have to be fit to the size of the bore,you place them in the cylinder and check the gap with a feeler gauge if no gap the you take a file and remove mettal untill you have the correct gap,then fit to the piston and install.Only putting in a few is a waist of time. Was the noise there before the mechanic mess with it? Well, you know it all started with the worn out plastic wheel of oil pump you know..engine ceased as I was riding one night around 10.30 pm far away from home....happened in an area you had only coconut lands....It was scary...after the cease I tried really hard to start it thinking it was some minor issue.. Then at the garaj nearby next day the guy tried to start it...actually it was starting but without oil running engine was two tight..He gave up! Then I took it to another mech who worked on carb, and tried full time to start it....actually it did start and had few runs also...it was at his I first heard this strange fut sound once...he opened the engine on my force ( he didnt like opening it as he didnt suspect it was some serious issue ) However, I forced ad we got to know oil sump filter was clogged and the pump wheel was shot and in oil there was worn out metal...we installed wheel and bike was starting on and off...problem was still there...they didnt think they should install new rings... Then I took bike to the mech who fixed my other bike really well..He removed all the engine parts and there was a small play in rods.. we put new genuine rods...bought rings matching the bores at the vendor but after installing all 5, the mech said it was too tight...so he said he would mix new with old at each piston and we fitted the engine...initially it started really well..but not for long ...since engine was ok I thought various reasons were behind not starting...After fitting the engine was of course rough and noise was strange..some deep steady on with some fut fut beat...mech cleaned all the valve deposits to offer perfect shut...He said we would put rings this way and see...the strange noise and poor pick-up..reluctance to start...now am pretty sure its due to this ring problem...I told him and said we should install new rings...He agreed..
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