scotty Posted March 10, 2007 Report Share Posted March 10, 2007 Having problems with my slimline bultaco! at first the carb wouldn't flood (tickle) to start her so ive stripped the carb down and cleaned through all jets/pipes etc! got the carb to flood( the bowl gasket was badly cut and wouldn't allow the float to rise properly!) now got the bike running but theres petrol rising up and coming through the button you push down to flood the carb with, So the float height wrong somehow and allowing the petrol to rise to high? ive had the carb on/off umpteen times and are now starting to get p*****d off trying to set it up correctly its an amal 627 bolt on type! ive set the airscrew 1 1/2 turns out from fully closed as far as i know the float height cannot be altered! anyone know how to set these up correctly as its now driving me nuts! the bikes runs and pulls super for an 1971 bike when it runs! p.s i think the mk1 ossa mar uses the same carb??? thanks in advance lads! Quote Link to comment Share on other sites More sharing options...
scotty Posted March 10, 2007 Author Report Share Posted March 10, 2007 Having problems with my slimline bultaco! at first the carb wouldn't flood (tickle) to start her so ive stripped the carb down and cleaned through all jets/pipes etc! got the carb to flood( the bowl gasket was badly cut and wouldn't allow the float to rise properly!) now got the bike running but theres petrol rising up and coming through the button you push down to flood the carb with, So the float height wrong somehow and allowing the petrol to rise to high? ive had the carb on/off umpteen times and are now starting to get p*****d off trying to set it up correctly its an amal 627 bolt on type! ive set the airscrew 1 1/2 turns out from fully closed as far as i know the float height cannot be altered! anyone know how to set these up correctly as its now driving me nuts! the bikes runs and pulls super for an 1971 bike when it runs! p.s i think the mk1 ossa mar uses the same carb??? thanks in advance lads! sorry forgot to add the float bowl gasket is just a paper ring? ie it does not seperate any holes or cutaways in the float bowl area so this proberly wont help with the above problems? Quote Link to comment Share on other sites More sharing options...
bultaco49 Posted March 10, 2007 Report Share Posted March 10, 2007 (edited) Hi Scotty If your carb is flooding when running it will be either the the needle valve not seating properly or float punctured and sinking. Check to see if the float will float in a bowl of petrol. Blow through the petrol inlet banjo while holding the needle vale shut. If either are faulty they are available from Bultaco uk, Hitchcocks or Surrey Cycles (All have web sites). Amal float height is not adjustable so here is a handy site which will give Mk 1 assembly details to check. http://www.ingfatrygg.se/amal.html#toc or I have a PDF manual for Mk. 1 and 2 concentric carbs I can send you to help out Tim Edited March 10, 2007 by bultaco49 Quote Link to comment Share on other sites More sharing options...
woody Posted March 10, 2007 Report Share Posted March 10, 2007 The float isn't meant to be adjustable but people who like to tinker make it adjustable by warming the tangs on the float that hold the needle and then bending them from their normal horizontal attitude into a different position which will raise or lower the float from standard. Why? - no idea, but may be worth checking yours to see if they've been altered. If they aren't in line with the horizontal top side of the float then they probably have. This is generally unlikely though and as per the post above the problem is more likely to be a faulty float or sticking needle. The bike should run fine with the Amal as long as it is in good nick. Quote Link to comment Share on other sites More sharing options...
scotty Posted March 11, 2007 Author Report Share Posted March 11, 2007 Thanks for the replies! ive had another look and the floats fine and the needle valve shuts off (removed the float bowl and connected the fuel pipe so it could fill up whilst looking at it!) BUT! the float comes up to high, I supose just past horizontal this is where its overflowing! and not shutting off like it should so perhaps like Woody says this might be why sometimes people bend these tangs, Im going to have another go at it if no joy ill buy a new float ,incidently the carb looks quite new as its an Amal made in england? also notice thats theres hell of a lot of play at the needle valve end where it slides into the plastic float tangs ,poss 3mm is this normal as this would affect the height and shut off as and when the float rises and falls? (still cant believe how the bike pulls and goes despite its age! had a 77 350t once and i reckon this m80's got a better engine, much more usable!) Quote Link to comment Share on other sites More sharing options...
totalshell Posted March 18, 2007 Report Share Posted March 18, 2007 needle valve is like a light bulb its either on or off open or closed, if there is a tang to bend that affecta the valve movement 1/16th of an inch should be more than enough movement to close the valve Quote Link to comment Share on other sites More sharing options...
scotty Posted April 7, 2007 Author Report Share Posted April 7, 2007 Right ive now replaced the ign side crankseal ( didnt bother with the clutch side one for now as the bike dosen't smoke much!) adusted the plug and points (these will need replacing soon as theres a small amount of pitting evident!) the bike now starts 1st/2nd kick ive got a great mid to top end but from idle to half throttle the bikes useless ie i have to give it plenty of revs to get it pulling away! the bike ticks over ok but like said the lower revs are useless!!!! can anyone shed any light on this? the carbs been cleaned again!!! petrols been changed, new spark plug fitted! the fuels reaching the carb ok! Quote Link to comment Share on other sites More sharing options...
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