Hey Everyone, Fixing a Triumph Sprint and I am having some problems. It's been sitting for a number of years and didn't want to start, so after taking out two of the spark plugs and cleaned them, it fired. We only managed to get two out because the third one looks very tricky without the right spanner. It fired a couple of times, but was interrupted by the drain tube coming from the air box (I think) which was pouring out a horrible red coloured fuel. It was also coming out of the far side air intake. I thought that it must be the carbs (at least one). Probably the float was stuck. I Took the carbs out and cleaned them all. One slide was stuck, but all the floats seemed to move fine. I cleaned them all regardless. After reinstalling the carbs - and heating the two accessible spark plugs with a blow torch, it ran only on two cylinders mind. And the fuel was still pouring out, but in a slightly better colour this time. On top of this, after shutting down the bike, trying to rev all 3 cylinders into life, we realised that not only had we filled the garage with a thick smoke, but the far side exhaust had been spitting out a fuel + oil mixture EVERYWHERE, as had the far side air intake. Any ideas? Thanks in advance for your time and help!
I am no mechanic so probably talking total rubbish but if the fuel tap was left in the prime position for a long time, the petrol could leak into the bores and airbox if the floats were stuck. It may take a lot of cleaning to get the crap out of the carbs, have you tried ultrasonic or just a bit of wire and blowing through? You say the fuel looked a better colour after cleaning, maybe the tank is full of water and rust,have you flushed it out?? I assume the head gasket had not blown initially and thats why the bike wasnt used. You are right about needing a special spanner for the one plug, Triumph do one but I think they are dear, try ebay maybe?
Hi Dave Is it worth stripping down the floats completely? I only checked the movement of the little float thing, I didn't take it out incase I accidentally move the float level. The Fuel tap idea is a possibility, is the cure to that just running it out? and I'll check ebay, if not it will have to stay in ahah!
The tank will need flushing out probably, the best way i believe is to put some ball bearings or nuts inside the tank (after removing it of course) and shaking the tank with a small amount new clean petrol in. ( look on the net, some say to use vinegar, some coke, and there are specialised products avaiable,I do not know which is best). Keep shakng and flushing till the fuel remains clean. You can also get products to seal the tank after. The petrol tap has 3 positions, if the pointed side points up it is on prime, horizontal is normal use and pointing down wards is reserve. The latter two positions only flow fuel when there is a vacuum form the vac pipe, the prime allows fuel all the time. I have never had my carbs apart coz its a fiddly job and I have big hands and cannot get in easily,there are little o rings and jets that wear out in there as well as the float sticking. sorry I cannot be more help
Ahh okay, so when it's running the the valve should be turned - didnt know that! Might be why there is petrol coming out if there is too much. As for the tank we turned the tap on and emptied some into a clear glass, the fuel in the tank looks fine, it must of been from the bowls or something. Am I right in thinking that the tube i described is from the air box? Its quite a thick tube, just wondered how fuel would get in there.
there is a tube on the airbox I believe, never took it off mine tho, and I think there should be a plug at the bottom end which has to be drained every so often. I know that fuel gets in there if the floats get stuck,have seen a few owners of T3 bikes in forums who have had fuel pouring out.
Which ever way you look at it Callumwk the carbs are flooding which means the float valves are not stopping the fuel comming in to the carbs, you will have to strip the carbs and if required replace the needle valves, they are rubber cones on the end of a brass spindle connected to the float, if you replace them which I think you will have too you will need to check and maybe re set the flote hight that is easy using a rule to measure from the carb flote bowl joint to the top of the float and bending the tag on the end of the float with the carb upside down without you touching it until it is correct, it is correct as others have said not to leave the fuel tap on prime but if the needle valves are good it still should not overflow the carbs, I would also check the sump oil with all that fuel around to make sure it is not full of petrol if it is you will need to change the oil, using a torch have a look in the tank and see if it there is water or crap in it ? remember fuel floats on water so if there is any in there you will see bubbles of it on the bottom of the tank, I get the third plug out with a short box spanner and an allen key in the end until it has unscrewed a bit and then use just the box spanner, they are not expensive. hope this helps Keith.
Thanks, I will look into everything you have said, I did consider the allen key trick, but I don't have any big enough.
