There's an old saying in medical diagnosis: if you hear hoofbeats, it could be zebras, but it's probably horses. (at least in Chicago; for our African friends, YZMV). Eliminate the most likely before you go searching after the less probable.
If it was running fine until you changed/fixed something (in this case, cables and linkages), look first at the things most directly connected/related to those that you fixed: the carbs synchronizing linkage, the choke linkage, &c.
Good luck.
High idle
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Huib
Re: High idle
Boring to oversize and oversize plates is the way to go if there is any light visible. It is what the better carb overhaul companies of which there are fewer and fewer do.
As I always managed to find new or good carbs so far I have never gotten around to trying it. On new carbs there is no light at all around the plates.
The plates are somewhat oval and have an edge under an angle. The angle is stamped on the plate. To get the proper angle is easier than it seems. After reboring till fully round measure the new bore. Then machine a rod of material (brass) to exactly fit the bore. Than cut slices under the required angle.
I wonder if it would be a good idea to make the new plates out of a modern plastic.
Of course you have to machine the spindle or make a new spindle.
I wonder if it is a good idea to use bush bearings from a company like SKF. They have a range of bush bearings with very special coatings. It may also be an idea to coat the spindle. Ceramic coatings and the like are not that expensive.
Vital is to be able to measure the flow through each of the barrels of each carb and balance it exactly before you put the carb on. I haven't figured yet how to do that easily.
As I always managed to find new or good carbs so far I have never gotten around to trying it. On new carbs there is no light at all around the plates.
The plates are somewhat oval and have an edge under an angle. The angle is stamped on the plate. To get the proper angle is easier than it seems. After reboring till fully round measure the new bore. Then machine a rod of material (brass) to exactly fit the bore. Than cut slices under the required angle.
I wonder if it would be a good idea to make the new plates out of a modern plastic.
Of course you have to machine the spindle or make a new spindle.
I wonder if it is a good idea to use bush bearings from a company like SKF. They have a range of bush bearings with very special coatings. It may also be an idea to coat the spindle. Ceramic coatings and the like are not that expensive.
Vital is to be able to measure the flow through each of the barrels of each carb and balance it exactly before you put the carb on. I haven't figured yet how to do that easily.
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tim
Re: High idle
Solex's are very poor castings. I was working on a friend's 35mm and noticed a hole in the venturi due to the thin casting. - I used araldite to repair. Moral is you could easily wreck a carb by over machining.
I am with Huib that if you can't set the butterflys as nearly shut then look for another second hand pair. I dont think this is Sam's problem however. If you take out the butter flys dress them lightly with 600grade to remove any high spots to facilitate a better closing position.
John's maybe just a synchormnisation problem. Shut the no 3/4 carb right down and adjust the balance to minimum revs and start again with the balancing. Also put a second spring on the throttle. I use a medium light coil spring from the throttle lever back to where the actuation lever is bolted. Is the idle smooth or lumpy.
I am with Huib that if you can't set the butterflys as nearly shut then look for another second hand pair. I dont think this is Sam's problem however. If you take out the butter flys dress them lightly with 600grade to remove any high spots to facilitate a better closing position.
John's maybe just a synchormnisation problem. Shut the no 3/4 carb right down and adjust the balance to minimum revs and start again with the balancing. Also put a second spring on the throttle. I use a medium light coil spring from the throttle lever back to where the actuation lever is bolted. Is the idle smooth or lumpy.
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jogo48
Re: High idle
Ed said (at least in Chicago; for our African friends, YZMV). I'm not from either Chi-town nor from anywhere in Africa. Ed, that may be the problem in my not understanding what your Chicago/Africa comment means.
Please explain.
If is something "hi-falutin" then I can 'use it' myself as soon as the opportunity occurs.
Thank you for the Zebra/Horse joke ! But, have you considered that it just might be stampeding cattle or even buffalo (the hoofed animal, not the city) ? And, if it somehow - in any sense - related to Fulvias, please explain that in 4 color detail.
Please explain.
If is something "hi-falutin" then I can 'use it' myself as soon as the opportunity occurs.
Thank you for the Zebra/Horse joke ! But, have you considered that it just might be stampeding cattle or even buffalo (the hoofed animal, not the city) ? And, if it somehow - in any sense - related to Fulvias, please explain that in 4 color detail.
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Ed Levin
Re: High idle
Jogo,
At least in the US. doctors being trained in diagnostics are taught, when they hear hoofbeats, to think it much more likely that the sound is being caused by horses than by a herd of zebras. In other words, they are taught to first consider the most likely cause of the symptoms that are in front of them, and only once they have ruled out the most likely cause should they examine ‘exotic’ explanations. I’m not a doctor; I’m not even sure why I know this little bit of medical lore.
But in one of life’s little coincidences, just a couple hours after posting my comments, I had to take my wife to a specialist doctor for a minor malady. During that visit, the doctor confessed that he wasn’t completely certain what was causing her ailment, but he speculated on the most likely cause, and used the very same ‘suspect horses before zebras’ metaphor. (Although, I hasten to add, my wife was not impressed when I brought up my related post on Viva-Lancia).
In any case, the ‘suspect horses before zebras’ metaphor only makes sense to those living in an area where zebras are less common than horses. I know that Sam is located in (or near) Chicago; even though I don’t imagine there are a lot of horses in his neighborhood, horses would still be considered far more common than zebras. However, Viva-Lancia forums are nothing if not global in their reach; a number of English-language participants live in South Africa (or at least southern Africa). I was merely acknowledging that there may be places in the Lancia world where the metaphor works less well than it does in the US or the UK. Depending upon where you live; your zebras may vary...
But the general rule of diagnostics remains this: suspect the most likely first. I don’t believe that Sam’s idle problem sprang out of nowhere, given his explanation of the linkage adjustments he had recently made. It may be, as others have suggested, that the problem is due to something completely unrelated to the linkage work–an air leak in the carb gasket (or elsewhere), but this sounds to me like a “zebra”.
I hope that explains my previous comments. High-fallutin' or not? You'll have to judge.
At least in the US. doctors being trained in diagnostics are taught, when they hear hoofbeats, to think it much more likely that the sound is being caused by horses than by a herd of zebras. In other words, they are taught to first consider the most likely cause of the symptoms that are in front of them, and only once they have ruled out the most likely cause should they examine ‘exotic’ explanations. I’m not a doctor; I’m not even sure why I know this little bit of medical lore.
But in one of life’s little coincidences, just a couple hours after posting my comments, I had to take my wife to a specialist doctor for a minor malady. During that visit, the doctor confessed that he wasn’t completely certain what was causing her ailment, but he speculated on the most likely cause, and used the very same ‘suspect horses before zebras’ metaphor. (Although, I hasten to add, my wife was not impressed when I brought up my related post on Viva-Lancia).
In any case, the ‘suspect horses before zebras’ metaphor only makes sense to those living in an area where zebras are less common than horses. I know that Sam is located in (or near) Chicago; even though I don’t imagine there are a lot of horses in his neighborhood, horses would still be considered far more common than zebras. However, Viva-Lancia forums are nothing if not global in their reach; a number of English-language participants live in South Africa (or at least southern Africa). I was merely acknowledging that there may be places in the Lancia world where the metaphor works less well than it does in the US or the UK. Depending upon where you live; your zebras may vary...
But the general rule of diagnostics remains this: suspect the most likely first. I don’t believe that Sam’s idle problem sprang out of nowhere, given his explanation of the linkage adjustments he had recently made. It may be, as others have suggested, that the problem is due to something completely unrelated to the linkage work–an air leak in the carb gasket (or elsewhere), but this sounds to me like a “zebra”.
I hope that explains my previous comments. High-fallutin' or not? You'll have to judge.
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Shaun Pond
Re: High idle
In some non-medical fields, where both horses and zebras are scarce, I believe that this same principle is referred to as "Occam's Razor".
Or, perhaps, in this instance, as Occam's Solex Adjustment Tool. I'm pretty sure that, were he on this list, Occam would echo Ed's suggestion that the search for the problem start with the last sub-systems touched, and then work outwards.
My Fulvia idled high after I replaced the porous gasket/heat shield thing, and it was (as Huib indicates here) the lever making contact with the new gasket. A bit of work with a file and dremel fixed it.
Regards
Or, perhaps, in this instance, as Occam's Solex Adjustment Tool. I'm pretty sure that, were he on this list, Occam would echo Ed's suggestion that the search for the problem start with the last sub-systems touched, and then work outwards.
My Fulvia idled high after I replaced the porous gasket/heat shield thing, and it was (as Huib indicates here) the lever making contact with the new gasket. A bit of work with a file and dremel fixed it.
Regards
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Ed Levin
Re: High idle
Shaun,
With all due respect (and the acknowledgment that it's been a very long time since I taught critical theory), if memory serves, Occam's Razor suggests that the simplest, most 'elegant' explanation is the best. This isn't quite the same principle as the 'suspect horses before zebras' rule, which suggests that the most blatantly obvious explanation is the most likely. (Although I'll confess that this may seem like hair splitting in the context of ll a discussion of a couple of Solexes that seem to be idling too high.)
In this case, however, Sam'se answer may be both the simplest and the most obvious. As I've said, my money is on those newly lubricated cables/linkages; probably either an over-tightened throttle cable or misadjusted throttle linkage, either of which isn't actually allowing the throttle plates to close fully.
With all due respect (and the acknowledgment that it's been a very long time since I taught critical theory), if memory serves, Occam's Razor suggests that the simplest, most 'elegant' explanation is the best. This isn't quite the same principle as the 'suspect horses before zebras' rule, which suggests that the most blatantly obvious explanation is the most likely. (Although I'll confess that this may seem like hair splitting in the context of ll a discussion of a couple of Solexes that seem to be idling too high.)
In this case, however, Sam'se answer may be both the simplest and the most obvious. As I've said, my money is on those newly lubricated cables/linkages; probably either an over-tightened throttle cable or misadjusted throttle linkage, either of which isn't actually allowing the throttle plates to close fully.
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Huib
Re: High idle
This all takes some studying, guys. Since the last couple of years I have become rather simple minded. I figure if one has to study it, it is fantasy because if it is reality, you can see it.