jet sequence on a bink’s carb

[jonathanjoy]

Hi
I’m having problems with flooding on a 3 jet bink’s. Does anyone know the jet sequence, i.e is the smallest jet near or furthest from the bell mouth etc it makes a difference as it makes it higher or lower than the petrol level. (the float needle seems fine)

[BRIAN MARSHALL]

Smallest nearest the bellmouth. Jim Best once related to me the way to set the float height…. With the bike off the stand, on level ground and upright, using a small mirror to see inside the bellmouth, gradually swing the float chamber forwards, if a R/H float chamber, backwards if a L/H float chamber, until you just see a blob of petrol appear on the end of the smallest jet. Dry it off with a tissue and see if another blob of petrol appears. Then move the float chamber fractionally back, so that the petrol level is JUST below the top of the jet, so it can be sucked out by the venturi effect by the incoming air, and tighten the bottom banjo bolt to lock the float chamber in position.
Brian

[jonathanjoy]

Thanks Brian, Mine seems to be with the smallest furthest from the bell mouth, this is the jet wich is flush, the other two have raised tubes. So is the sequence smallest flush jet nearest the bell mouth then the largest with the longest tube in the middle finally mid jet nearest the inlet port ?
ps this means the smallest jet is to the rear of the bike and hence highest in relation to the petrol float level ?

[BRIAN MARSHALL]

Hi, your jets are in the wrong way round, so with the shortest nearest to the bellmouth, then the intermediate one, and then the tallest one furthest from the bellmouth, you should be OK, when you have gone thru’ the Jim Best setting up procedure. Good luck, and let us know how you get on !
Brian

[jonathanjoy]

probably why it won’ start 😳

[jonathanjoy]

Hi I’ve just dismantled it, The housing for the three jets has the two tubes soldered in place with the longest in the middle, I can’t imagine that this has been rearranged, its also impossible two rotate it 180 as theres a cut out and spigot to prevent this, so the flush jet has to be nearest the engine in my case !. It seems logical to me that the longest tube is nearest the engine then the smaller tube in the middle and finally flush so it reflects the fuel level. so I’m at a loss, i’d be grateful if some one with a late 20s flyer fitted with a 3 jet binks could have a peak down the bell mouth and have a look

[BRIAN MARSHALL]

It’s been modified… All three jets, complete with their tubes, should freely unscrew from the underside, and they should have a square section to suit the jet key, unlike the hexagon on Amal jets. I’ve got about 15 of the things in a box, and they ALL have the jets in the positions I have described !!
Brian

[jonathanjoy]

Thanks Brian, The jets are square section and unscrew, but the tubes are soldered in place. Are the tubes normally connected to the jets ? I’m wondering if I should unsolder and swap the tubes around, what do you think ?

[jonathanjoy]

Hi I’ve uploaded pictures of the jet block, If I move the tubes the throttle slide will not close, also the air slide seems to act as a shield at low openings, should the throttle or air slide be nearest the bell mouth ?[attachment=1:23y3cwdn]WIN_20160524_07_43_50_Pro.jpg[/attachment:23y3cwdn]

[jonathanjoy]

[attachment=0:310urz99]WIN_20160524_07_43_56_Pro.jpg[/attachment:310urz99]

[BRIAN MARSHALL]

Time for me to eat ‘Umble Pie ! I blame it on a senior moment, combined with a strong dislike of Binks carbs… This morning I went to my boxes of Binks bits and must retract previous statements !! Sorry to have confused Jonathan and any one else reading my drivel. The tubes are fixed in the jet holder and do not unscrew on the later Amal/Binks. Not only that, the jet with no vertical tube is at the point furthest from the bellmouth, and the longest tube is in the middle of the three.
Brian

[jonathanjoy]

Phew ! that’s a relief.
I was about to reposition the tubes and rotate slides etc. although the design doesn’t seem logical, I prefer your original layout statement. So I think its just a question of float level and making sure the needle seats. As for senior moments, I’ve just spend two days installing an inline tap to stop the oil (from my Douglas’s oil tank) gradually filling up the crankcase when parked , but immediately realised all I needed do was to close the needle valve on the drip feed !!!!! 😳

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