March 9, 200620 yr comment_106300 hey guys well i have sorted out a major air leak, so that problem should be all gone now ... The new problem - the car free revs - even with the idle screw set at the lowest, it revs at over 3,000RPM. This is with the mixture screw set about 1 1/2 turns out. This is with the throttle gear returning to the closed position (e.g. the throttle cable isn't tight and holding the throttle open. ..) The jets in it are 130 primary, and 132 secondary. It is an automatic choke model, but the choke valve is all the way open so should have no affect ... The motor is a 4k .... ARG! ANY help would be great guys, cars been off the road for almost a week now :P Cheers, Dyzza (this problem is now fixed ... scroll down the bottom for the new one - motor knocking~!) Edited March 17, 200620 yr by Dyzza Report
March 9, 200620 yr Author comment_106309 hey hmm i don't think that will make the difference ... Do these automatic chokes control the air/fuel ratios at all ? I thought all they did was close off airflow coming down the barrels and hence having a higher fuel to air mixture going into the motor until it was warm enough ... then it opens and the mixture goes to something more appropriate ... They are a bit of a hassle to disconnect, but i will give it a go at some point ... Any other suggestions people ? Cheers for the reply Tedmeister Dyzza Report
March 9, 200620 yr Author comment_106317 Could be a stuffed carby. My old 4K aisan did the same thing, couldn't adjust it to idle below 2000 RPM supposedly this carby is in good working order. its nice and clean with no loose throttle parts or any of that ... Its not that i can't 'adjust' the idle - I'm not given the chance. its revving at 3000RPM with the idle screw at the least possible - the stopper isn't even touching the screw. The throttle linkage sits at the closed position (no tension in the accelerator cable) but it still does it ... Cheers Report
March 9, 200620 yr Author comment_106325 Supposedly never cuts it for me... OPen it up, they are the piss easiest carby to work on ever Doublecheck everything, especially float level hey yeah i have pulled it apart and cleaned what i could with carby cleaner and all that, i have never been shown how to adjust the float level ... how do you do that ? What sort of problems could an incorrectly set float level give ? Cheers Report
March 9, 200620 yr comment_106327 supposedly this carby is in good working order. its nice and clean with no loose throttle parts or any of that ... Its not that i can't 'adjust' the idle - I'm not given the chance. its revving at 3000RPM with the idle screw at the least possible - the stopper isn't even touching the screw. The throttle linkage sits at the closed position (no tension in the accelerator cable) but it still does it ... Cheers Just check that the second barrel butterfly hasn't been adjusted up ,sometimes they need to be adjusted up to give it more signal with large camshafts. Also an air leak will do the same thing when it gets hot,does it idle ok when its cold??. Report
March 9, 200620 yr Author comment_106328 Just check that the second barrel butterfly hasn't been adjusted up ,sometimes they need to be adjusted up to give it more signal with large camshafts. i'll have a check of that ... sounds like a probable answer! I guess its not hard to adjust the butterfly ? Also an air leak will do the same thing when it gets hot,does it idle ok when its cold??. when its cold it does the exact same thing ... i'll definitely check the position of the butterflies ... Cheers, Dyzza hey to reiterate ... does that mean that the secondary butterfly is adjusted to be open a little bit (in this case - maybe its sitting open enough to fuel the motor to rev this much ...) so upon full throttle both sides open fully without any of the secondary being left partially closed ? Anywho thats my interpretation ... feel free to correct me ! Cheers guys Report
March 10, 200620 yr Author comment_106384 hey guys ... Well it was a major air leak that was causing the problem ... something i thought i had sorted. Thanks for all the help ... The new problem: the motor is knocking ... I'm putting a timing light on it tonight when my old man gets home, any other suggestions ? Ive made it richer in case a lean mixture was causing the knocking, but that didn't make much of a difference ... I wouldn't have thought changing a carby would alter the timing at all (from 1 weber to another weber ... ) ... Cheers, Dyzza Report
March 10, 200620 yr comment_106388 Knocking coud be piston slap. a 4AC i had did that pretty bad. haha. Report
March 10, 200620 yr Author comment_106400 yeah I'm gonna put a timing light on it tonight and try and sort it out ... any other suggestions ? :P Report
March 10, 200620 yr comment_106405 hey guys ... Well it was a major air leak that was causing the problem ... something i thought i had sorted. Thanks for all the help ... The new problem: the motor is knocking ... I'm putting a timing light on it tonight when my old man gets home, any other suggestions ? Ive made it richer in case a lean mixture was causing the knocking, but that didn't make much of a difference ... I wouldn't have thought changing a carby would alter the timing at all (from 1 weber to another weber ... ) ... Cheers, Dyzza Just go back to the basics and check everything,if you have the vacuum advance connected when you did the timing last time with the air leak you would have had a weak signal but now with more vacuum it may be pulling the advance unti too far around. P.S. timing should be checked with all vacuum lines removed and plugged,but you knew that anyway RIGHT!!!!. Matt Report
March 11, 200620 yr Author comment_106538 Just go back to the basics and check everything,if you have the vacuum advance connected when you did the timing last time with the air leak you would have had a weak signal but now with more vacuum it may be pulling the advance unti too far around. P.S. timing should be checked with all vacuum lines removed and plugged,but you knew that anyway RIGHT!!!!. Matt hey yeah i did the timing with the vacuum lines removed - it was on 20 degrees advanced .. yikes... its back to 10 now. still making the noise. i don't think its the motor knocking, sounds like somethin in the rocker cover ... hard to hear in the engine bay .. but in the car its way clear. It does it when the motor idles, and when it revs. the light knocking increases in frequency with the increasing RPM ... What does a blown headgasket do ? or one on the way out ... never had to deal with it. It just doesn't make sense - making this noise after the carby swap. I'm pretty sure its not a carby noise ... Cheers, Dyzza Report
March 11, 200620 yr comment_106576 If its a bottom end knocking noise it could be low oil pressure. Got a guage on that engine? (if you do get an ELCTRICAL one, not a mechanical guage) I shit you not, find a stethoscope... you'll pinpoint the knock quicker Just a bit weird why its only happening now after the carby change,didn't drop anything down a certain hole did we. Go the stethoscope,or a nice thin long screwdriver on your ear.Just be careful where you point it. Matt Report
March 14, 200620 yr Author comment_106871 hmm Yeah nick it does sound like a low oil pressure noise ... Nah i'm well aware of the dangers of dropping a nut down the intlet manifold ... done that once or twice. thank god for those magnet stick things! I'll rig up a oil pressure guage and see whats the haps ... Cheers, Dyzza Report
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