daverclasper Posted March 21, 2017 Report Share Posted March 21, 2017 Hi Having a few issues with carbs at the mo which I'm trying to sus out and will prob go into more detail later. Have to a 200 mile trip shortly which I'll take steady. Plugs colour is a very pale grey, flakey coating which I think suggests weak mixture. just wondering if this may cause over heating damage to pistons/valves. Any help great please. Cheers, Dave Link to comment Share on other sites More sharing options...
Pete Lewis Posted March 21, 2017 Report Share Posted March 21, 2017 Yes in general a lean mix has a higher temperature I would richen it a little . you want a light brown rather than heading to grey or white pete Link to comment Share on other sites More sharing options...
daverclasper Posted March 21, 2017 Author Report Share Posted March 21, 2017 Thanks Pete No time before I do trip, to experiment with plug chops and haven't yet got a feel/ear for the lifting piston technique. I was thinking maybe 1/2 a turn out out each mix screw to improve, or should I go more. Concerned about pos damage to engine in short term, until I get time to mess about with it. Cheers, Dave Link to comment Share on other sites More sharing options...
Pete Lewis Posted March 22, 2017 Report Share Posted March 22, 2017 1/2 turn is too much I would recomend 1/8 to 1/4 increments especially if its running pretty much ok dont get paranoid about it, if its not misfiring or hic cups on accelerating dont worry too much piston lift is not a dark art but its a small lift and listen to a hint of change so if weak a 2mm lift will drop the idle by about 50 rpm rich will raise 50 rpm If ok not much happens at all this small change only occurs for a few seconds with it idling must have air cleaners on, pointless with them off. So dont expect it to stall or race , its small quiet changes , it will do dramatic changes if you yank the piston up thats not the plan. rise the pin till you just feel it touch the piston, then lift just a few mm. Link to comment Share on other sites More sharing options...
dougbgt6 Posted March 22, 2017 Report Share Posted March 22, 2017 Air cleaners on? Never heard that before. Haynes shows it done with air filters off. Or is this an anomaly of CD150s as opposed to CDSE150s? Or am I confusing cleaners and filters? If so what are cleaners? So many questions! Confused of Berkshire Link to comment Share on other sites More sharing options...
dave.vitesse Posted March 22, 2017 Report Share Posted March 22, 2017 If you setup the mixture with the air cleaners not fitted when you refit them as they restrict the airflow the mixture would become rich. You remove them to balance the carbs. then refit and setup the mixture. Of course the air cleaners should not be blocked. As I originate from Tunbridge Wells I must be disgusted(ing) from...... Dave Link to comment Share on other sites More sharing options...
Pete Lewis Posted March 22, 2017 Report Share Posted March 22, 2017 i cant see why any book would advise setting things with the filters or cleaners or mufflers or ram stack sock being left off but they do !!!!! with carbs having lifting pins it easy , if they are nor seized up, any adjustments should be done in a as running condition, not have half the car missing. emmission controlled carbs have them deleted as they dont expect anyone to twiddle with the factory settings same as blanked off idle screws etc. of which most tamper proofing has long been ditched . most people of our ages cant hear or detect the rev changes or feel the pin contact so ts all a waste of time worried from luton !!! 1 Link to comment Share on other sites More sharing options...
dougbgt6 Posted March 22, 2017 Report Share Posted March 22, 2017 But, I have no pins! What am I to do? Deeply concerned of Twyford Link to comment Share on other sites More sharing options...
dougbgt6 Posted March 22, 2017 Report Share Posted March 22, 2017 But seriously I don't use this method anyway. I use a vacuum gauge to set mixture and also timing. Here are a bunch of Americans showing how it's done. https://www.bing.com/videos/search?q=setting+carburetor+mixture+with+a+vacuum+gauge&&view=detail&mid=95232D306664DD80FE1395232D306664DD80FE13&FORM=VRDGAR Link to comment Share on other sites More sharing options...
Pete Lewis Posted March 22, 2017 Report Share Posted March 22, 2017 doug if yours are cdse ? the needles are set with the delrin washer about flush with the piston you dont need lifting pins sleep well Pete Link to comment Share on other sites More sharing options...
dougbgt6 Posted March 22, 2017 Report Share Posted March 22, 2017 Pete, mine are top adjusters so the needle and washer move up and down with....... adjustment. I don't see how I can flick the piston up, with the air filters on, if I don't have pins? Which is probably why I installed the vacuum gauge. The great thing about Alzheimer, you are constantly meeting new friends and finding things you've done that show you how clever you are (were!). Link to comment Share on other sites More sharing options...
Pete Lewis Posted March 22, 2017 Report Share Posted March 22, 2017 Yes Doug you cant do any of the pin lifting excercises the top adjuster needle have a small plasticy washer at the head of the needle If you pull the air piston assy out the std setting is this little washer sits up close to the base of the piston im sure they will let you out to play if you're good pete Link to comment Share on other sites More sharing options...
dougbgt6 Posted March 23, 2017 Report Share Posted March 23, 2017 Plasticy washer, yes. I dropped one while rebuilding my carbs on the conservatory table, could I find it? Eyesight also in decline. Link to comment Share on other sites More sharing options...
Pete Lewis Posted March 23, 2017 Report Share Posted March 23, 2017 heck Doug there's no hope you can make one out of the box you keep your teeth in wheres this going to get us ?? stop twiddling and drive like crazy Pete Link to comment Share on other sites More sharing options...
daverclasper Posted March 23, 2017 Author Report Share Posted March 23, 2017 Thanks folks Been giving the lifting pins another go. Idling at about 8000 revs. Twiddling about with slight, different setting of the mixture screws I think I can hear a change in revs up and down (and even staying the same!), though only for maybe a second and then then engine will stall. Is that supposed to happen? please. Dave Link to comment Share on other sites More sharing options...
Pete Lewis Posted March 23, 2017 Report Share Posted March 23, 2017 Dave, Heres hoping the 8000 idle is a typo .. If you only lift the piston about 2mm and it stalls its sounding very lean it shouldnt stall unless you are jacking the piston up too far. pete Link to comment Share on other sites More sharing options...
daverclasper Posted March 23, 2017 Author Report Share Posted March 23, 2017 Cheers Pete I meant 800 revs (doh) Will do some more fiddling. It's not missing or hiccuping on acceleration, though maybe short on power. (hard to know as engine is worn I think and never driven another to compare) Thanks, Dave Link to comment Share on other sites More sharing options...
Pete Lewis Posted March 23, 2017 Report Share Posted March 23, 2017 Even a worn engine shouod be quite lively and be enthusiatic even if it smokes and burns oil they should be a reasonable va va room , unless compressions are way too low Pete Link to comment Share on other sites More sharing options...
daverclasper Posted March 26, 2017 Author Report Share Posted March 26, 2017 Hi Did the 200 mile trip. Did a couple of plug chops and enriched mixture, though only got a grey plug colour. Averaged 30mpg at probably an average of 50mph using overdrive. Back in the city, did about 3 miles and looked at plugs, Very sooty and revs rising doing the lifting pin technique. Also the mixture screws were both 5 and 3/4 turns down which seems excessive. Always been prone to this. Very heavy fuel fuel consumption in town if mixture set something like for cruising. That's why I replaced the parts mentioned above. One thing, the points plate has only about 5mm vacuum movement at it's edge, due to the way it's been earthed, could be affecting mixture that much at idle?. Any ideas please. Cheers, Dave Link to comment Share on other sites More sharing options...
Pete Lewis Posted March 27, 2017 Report Share Posted March 27, 2017 The vac advance only gives better economy mainly when cruising , does affect acceleration , or performance in general. plugs will always show a more sooty deposit in situation of lots of acceleration like town driving the oil in the dash pot slows the rise of the piston and more fuel is pulled out the jet this would be the accelerator pump on a down draft carb, without it you will have a lot of flat spots when you open the throttles what needles are fitted ??? Number and letters on the boss at the end of the needle 1 Link to comment Share on other sites More sharing options...
daverclasper Posted March 27, 2017 Author Report Share Posted March 27, 2017 Thanks Pete Old needles 6J, as are new ones. Dave Link to comment Share on other sites More sharing options...
Pete Lewis Posted March 27, 2017 Report Share Posted March 27, 2017 6J is base CD150 for GT6 and Mk1 Vitesse ( thames barrier choke) 6AC for mk2 vit and GT6 which would have CDS ( adds a choke valve) But if you have CDSE ( choke valve and temp compensators etc. then the only spec shown is B5AJ being a biased top adjust needle and more inclined to remind me you dont have pancake air filters do you ??? Pete Link to comment Share on other sites More sharing options...
dougbgt6 Posted March 27, 2017 Report Share Posted March 27, 2017 There are two needles for CDSEs on Mk3s, don't know the numbers but they are pre and aft engine number KE0000. There is also a third needle for pancakes. Rimmers sell all three. I know this because Rimmers stitched me up with a carb repair kit containing the wrong jets. Link to comment Share on other sites More sharing options...
daverclasper Posted March 27, 2017 Author Report Share Posted March 27, 2017 Hi. No pancakes, standard filters and box. They are the Thames Barrier choke type, car Mk1 2Litre. I will try setting again with lifting pin. Is it just for a second that the revs will alter, and then back to normal or do something else if the pin is held up please?. Got a feeling that if I get that right at idle it will not reach a brown plug colour at cruising, though it will probably not miss or hesitate. Don't want to cause any weak running damage is main concern. Thanks Dave Link to comment Share on other sites More sharing options...
Pete Lewis Posted March 27, 2017 Report Share Posted March 27, 2017 You carefully lift the pin enough to just touch the underside of the air piston Then lift it about 2 mm and hold it there note the sensation of change which only lasts a few seconds, so you hear the short up speed , or a light falter, or if its right feel nothing Its small lifts and small changes , or a hint of change , if rich a quick upspeed of around 50 rpm if weak a short falter , and a small drop /hesitation if you get the pin and just yank it up expect it to stop or misbehave its very touchy feely Link to comment Share on other sites More sharing options...
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