Pete Lewis Posted October 25, 2022 Report Share Posted October 25, 2022 the common thing is popping especially any back fires is always condenser giving stray sparks pancake and KN type filters cost a fortune and can make good headaches as it completely upsets the fuel draw from the jet/needle there are very few alternative needles for strombergs and dont think about swapping to SU most just make the headache bigger despite more needles being available what colour wire is on your condenser ?? and is the dizzy lucas or delco ??? you dont wantif its a lucas rotor witha rivet in the sweep plate ...nightmare shutting the TC will richen the previous idle manifold mixture a bit as you blocked the throttle bypass (as it should be) Pete 1 Link to comment Share on other sites More sharing options...
dougbgt6 Posted October 25, 2022 Report Share Posted October 25, 2022 38 minutes ago, gtjoe said: Didn't touch needle setting Do you have the adjustment tool? Worth getting to avoid diaphragm damage. Doug 1 Link to comment Share on other sites More sharing options...
Pete Lewis Posted October 25, 2022 Report Share Posted October 25, 2022 i added two threaded screws to act as a tommy bar as if the adj nut is stiff you cant hold the small knurled top Pete Link to comment Share on other sites More sharing options...
gt6j Posted October 26, 2022 Author Report Share Posted October 26, 2022 Right got the carbs off and apart... have the tool to adjust if needed now. Have a question regarding float chamber section? Ones in there were not 16mm from lip of casing at all, have bent new ones to be 16mm from casing, however, with float chamber casing back on should you be able to blow thru the fuel inlet ok with the carb upright as I can't get air through it? Is that normal? Assumed when empty and upright should be able to blow thru as that's where fuel would come in? Also can't get injector tube out any tips welcome. Sorry this has turned into carb thread will look to see if covered elsewhere too. Link to comment Share on other sites More sharing options...
johny Posted October 26, 2022 Report Share Posted October 26, 2022 ok so you turned the carb upside down and meaured from the highest point of the float to the casing flange? I thought it was 18mm but maybe yours is different... Then with the carb the right way up you should be able to blow through the fuel inlet regardless of whether the casing is in place or not. If its blocked something is wrong☹️ 1 Link to comment Share on other sites More sharing options...
gt6j Posted October 26, 2022 Author Report Share Posted October 26, 2022 Wondering if I've got the measurment wrong now.. had a Google and found 16mm for 150cdev's. Can blow air through with the chamber case off so maybe wrong height. And yeah measured from highest point of float to lip of casing Link to comment Share on other sites More sharing options...
johny Posted October 26, 2022 Report Share Posted October 26, 2022 could be cos my measurement is for CD150. Anyway that shouldnt make a difference for the blow test and neither should installing the casing unless the chamber overflow is blocked. This is where the air should flow out as does the fuel if the float valve doesnt close properly... 1 Link to comment Share on other sites More sharing options...
Pete Lewis Posted October 26, 2022 Report Share Posted October 26, 2022 the normal std for cd/cds/cdse is 18mm as said a couple of mm wont change the fact you cant blow through so theres a blockage inthe valve the jet tube is pressed in you should not need remove it does your float have the twin valve arms as you can fit the float upside down have look here its not GT6 but the basics are all relevent Carburetors — Buckeye Triumphs pete 1 Link to comment Share on other sites More sharing options...
gt6j Posted October 26, 2022 Author Report Share Posted October 26, 2022 Well after pulling it apart and measuring again found that the new little needle valves were getting stuck shut. Put the old ones in and now can blow air through both carbs and they shut off when tilted upside down. I have got the new floats double sided Pete I think guessed which way round they went but I'm sure there must be right and wrong way. See how it runs tomorrow! Or doesn't 😂 Link to comment Share on other sites More sharing options...
gt6j Posted October 26, 2022 Author Report Share Posted October 26, 2022 Have had look on that site today and the videos they have on YouTube learnt alot very good Link to comment Share on other sites More sharing options...
johny Posted October 27, 2022 Report Share Posted October 27, 2022 Great, strange the valves stuck and maybe they would free up with some fuel through them or maybe its another example of poor quality replacement parts... Link to comment Share on other sites More sharing options...
Pete Lewis Posted October 27, 2022 Report Share Posted October 27, 2022 this shows the correct way up the float fits with the metal plate fuel side away from the valve there were some float needles valves made with no fuel outlet holes in the body of the valve supplied by them that should know better if you vave no fueling holes send em back do not adventure into Grose Valves they are not good these days Pete 1 Link to comment Share on other sites More sharing options...
gt6j Posted October 31, 2022 Author Report Share Posted October 31, 2022 Just to update before I get stuck into the coil/dizzy side.. I put carbs back together all seeming ok, back on car.. didn't idle smoothly at all and dying on idle quite a bit. No leaking of fuel as before. Sounds rough to me. Not on all cylinders. Weirdly fine when pulling away up through gears and doesnt hesitate at all but when slowing down to stop just dies or very nearly does. Also revs don't slow down very nicely seem to be very slow occasionally and dancing about. My carbs aren't the type that can be adjusted as I far as I'm aware now.. they have the pin held in by a grub screw but no adjustment from above, just the idle adjuster. Haven't adjusted them. Wondering if also fuel pump playing up but only prob is on idle. Sounds as though definitely not on all cylinders when idling but as said all ok once past 10mph or so pulls nicely. Will be replacing coil and electric bit in dizzy (points been taken out by PO). Has a lucas coil and delco dizzy. Weird how only at idle though. 🤔 Link to comment Share on other sites More sharing options...
Pete Lewis Posted October 31, 2022 Report Share Posted October 31, 2022 not a top adjuster but has TC this sounds a bit odd do you have the jet adjuster under the float chambers???? 1 Link to comment Share on other sites More sharing options...
gt6j Posted October 31, 2022 Author Report Share Posted October 31, 2022 7 minutes ago, Pete Lewis said: not a top adjuster but has TC this sounds a bit odd do you have the jet adjuster under the float chambers???? Doesn't have adjuster under the float chamber just a cap and has the groove in top of carb for the lock on the adjuster tool. Going to take another look tomorrow to make sure I'm locking that hex key in somewhere. It felt in and just span earlier didn't stop. When lifting the piston a tiny bit it died everytime I tried. Will try again make sure I'm definitely in far enough on the adj tool. Link to comment Share on other sites More sharing options...
chrishawley Posted October 31, 2022 Report Share Posted October 31, 2022 1 hour ago, gtjoe said: It felt in and just span earlier didn't stop Ah! Strombergs! The carb with the learning curve! I'm trying to get an idea as to how an 'ever rotating' allen key could occur. One possibility is that the needle (top right in photo) is not screwed on to its carrier (top left). The carrier has a little o-ring round it(bottom left) and the carrier sits up the piston against the toothy washer. Not it the picture is the grub screw on the side of the piston. This grub is not to lock the needle in position but rather to act lightly on the groove on the needle to prevent it from rotating when adjustment is being undertaken. If the adjustment is taken too far in an anticlockise direction it is possible for the needle to run off the thread of the carrier and the carrier can then rotate ineffectually. Well, that's my theory! Could be worth taking the pistons out, remove the grub screw and, using the adjustment tool, check the the needle in engaged with the carrier. Link to comment Share on other sites More sharing options...
Pete Lewis Posted November 1, 2022 Report Share Posted November 1, 2022 agree with chris the only other idea would be someone has swapped the air piston to a earlier type as for needle position there should be a small washer at the top of the needle this should as a base setting be level with the base of the piston time to remove the piston and have a good gander at just what is going on Pete Link to comment Share on other sites More sharing options...
Stratton Jimmer Posted November 1, 2022 Report Share Posted November 1, 2022 Chris's theory sounds good to me too. Link to comment Share on other sites More sharing options...
gt6j Posted November 1, 2022 Author Report Share Posted November 1, 2022 Again really appreciate the help here going a bit mad. Both needles were out, I don't think I was on them properly there is a hex slot afterall. Have set the washers flat with base of piston. Managed to get it to temp with choke on, let choke go and it splutters out. Doesn't sound smooth idling with choke on. Can rev it and will rev fine doesn't die but as soon as let up gas will die. Wondering if I've blocked somewhere with a gasket. Anyone know if carb to manifold gasket (where disc is) should just have one hole and what shape as old gaskets had split in them for little hole at side. New gasket seems to cover this up not sure if it's for separate idle bit on carb? Wouldn't idle mix just come through the main disc? Cheers for help again Link to comment Share on other sites More sharing options...
gt6j Posted November 1, 2022 Author Report Share Posted November 1, 2022 Also with choke on revs climb on their own slowly, they do stop but another symptom. Have bits for ignition side on way. Link to comment Share on other sites More sharing options...
Pete Lewis Posted November 1, 2022 Report Share Posted November 1, 2022 the small hole is the air bleed from the Temp compensators one advantage of gasket closing this is they wont misbehave any more same as closing the little TC plunger down set the idle screw from just touching the casting to 1.5 turns in on each carb should give you around 800rpm idle timing now how has that been set , another learning curve the damper ring with the timing marks on can loose its metalastic bond and the ring can actually turn on the pulley , have you tried set timming by ear , ie turn dizzy to get the best running and back it off a bit from best ??? do you have open breathers or a smiths emmision valve ??? pete 1 Link to comment Share on other sites More sharing options...
Ian Foster Posted November 1, 2022 Report Share Posted November 1, 2022 2 hours ago, gtjoe said: let choke go and it splutters out Have the carbs been balanced. If not there is not much chance of obtaining a decent idle. A flow meter is ideal (Crypton Syncrocheck, Webber or Gunsons Carbalancer), but a length of smallish diameter tube held in the carb throat and next to the ear, works surprisingly well. You'll need to slacken off the tie bar between the two throttle spindles and adjust each carb independently on the stop screws. (remember to retighten the tie connections afterwards) Ian 1 Link to comment Share on other sites More sharing options...
Pete Lewis Posted November 1, 2022 Report Share Posted November 1, 2022 our cars were all built before the days of serious emission controls and the carbs would habe been just set to a predetermined throttle stop and mixture jet/needle positions taken out a stillage and bunged on the engine with if twin the connecting rods nipped up there were no faffing about with any balancing on the engine dress or assy line gas flow checked carbs set witha controlled flow did not appear till the late 80s (in general) so you can mecanically set the idle screws and be pretty well in state of balance its not a dark art , having a balancer bought or homemade is good for peace of mind but never essential pete 1 1 Link to comment Share on other sites More sharing options...
gt6j Posted November 2, 2022 Author Report Share Posted November 2, 2022 Some good info again, appreciated! As unsure of age and if they work and for peace of mind (almost) today fitted new plugs, leads, distributor, coil. Set timing best could by ear. Adjusted floats to allow more fuel in carb after attenpting to set idle. got it to temp and idle but rough. when trying to lift pistons in carbs nearly dies, both carbs at max adjustment (needle up most fuel in) tried middle setting but is even unhappiest. Link to a video here not sure if it works! Don't know if related but when I put the carb adj tool into the hex slot putting pressure on the needle the revs climb. Maybe that's normal but maybe not! Link to comment Share on other sites More sharing options...
NonMember Posted November 2, 2022 Report Share Posted November 2, 2022 Increasing revs when you push down the piston, like the revs falling when you lift them, indicates that the mixture is too lean. If that's the case with the needle fully rich, then it suggests either the fuel level in the float chambers is too low or there's an air leak into the manifold. 1 Link to comment Share on other sites More sharing options...
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