STIG Posted July 13, 2015 Share Posted July 13, 2015 Hi all.im currently restoring a ferret scout car got her running with little effort carb leaking fuel and not ticking over correctly so so decided to refurb carb,came apart ok apart from when i unscrewed volume control screws one of them was broken off inside just past end of threads i can see the tapered end from the apature in carb it is siezed /stuck in there,has anybody had experience on this problem or is it case of get another carb?all help much appreciated. ...cheers Quote Link to comment Share on other sites More sharing options...
Diana and Jackie Posted July 13, 2015 Share Posted July 13, 2015 Is it actually stick in there? or is it difficult to turn whilst broken off, sometimes you can turn it by coaxing with a small screw driver. The other option is warm water, heat soak in penetrating fluid and try again, or a small hole down the middle of the mixture screws and use a screw extractor. Diana Hi all.im currently restoring a ferret scout car got her running with little effort carb leaking fuel and not ticking over correctly so so decided to refurb carb,came apart ok apart from when i unscrewed volume control screws one of them was broken off inside just past end of threads i can see the tapered end from the apature in carb it is siezed /stuck in there,has anybody had experience on this problem or is it case of get another carb?all help much appreciated. ...cheers Quote Link to comment Share on other sites More sharing options...
STIG Posted July 13, 2015 Author Share Posted July 13, 2015 Is it actually stick in there? or is it difficult to turn whilst broken off, sometimes you can turn it by coaxing with a small screw driver. The other option is warm water, heat soak in penetrating fluid and try again, or a small hole down the middle of the mixture screws and use a screw extractor. Diana Ive soaked it in plus gas to try loosen it up but no joy looks as if its been snapped for quite a while end of threaded part i took out was tarnished,its seems as if its been screwed in as far as it could possibly go and then some,going to take very small drill bit and extremely steady hands to drill and smallest extractor available. .o happy days...thanks for help..:kiss: Quote Link to comment Share on other sites More sharing options...
Diana and Jackie Posted July 13, 2015 Share Posted July 13, 2015 Get a very small screwdriver that will fill the hole as much as possible, sharpen it so the blade is sharp, place in mixture screw hole, with a carb body held firmly tap and rotate the screwdriver and tap (not hit violently), with luck the screwdriver will bite into the brass and the taps will loosen the screw whilst the screwdriver is being turned. Diana Ive soaked it in plus gas to try loosen it up but no joy looks as if its been snapped for quite a while end of threaded part i took out was tarnished,its seems as if its been screwed in as far as it could possibly go and then some,going to take very small drill bit and extremely steady hands to drill and smallest extractor available. .o happy days...thanks for help..:kiss: Quote Link to comment Share on other sites More sharing options...
sexton Posted July 15, 2015 Share Posted July 15, 2015 (edited) Wow, if the screw sheared trying to get it out, that stub remaining in the carb is really jammed in there tight. Those screws are steel. I doubt any kind of penetrant will free it up. I've taken some crusty old carbs apart and the only technique I have found to work in a situation like yours is HEAT. And I mean serious heat. It's nerve-racking but you've got to get the carb body around the seized part smoking hot. I have used one of those baby oxy-acetylene kits because they give you a seriously hot but very focussed heat. I don't know what the Solex carb body is made of but it's some kind of aluminum/zinc/tin alloy that is seriously dense and heavy. I thought the carb was cast iron when I first lifted one off. So I'm thinking it can take some heat, but the trouble with materials like that is they can go from looking OK to melting just like that. So it's impossible to describe how much heat to apply because it's such a judgement call, with bad consequences if you get it wrong. It may take multiple applications of heat. The sharpened screwdriver seems to be your only option for getting some torque on the stub after heating to see if it has loosened, but it also has the risk of peening the stub end over if you hammer the screwdriver in too hard, making it tighter in the threads. By the way, this idle control screw is unlikely to be the cause of the carb leak. That's more likely to be the accel pump diaphragms leaking, a major weakness of the carbs, IMO Malcolm Edited July 15, 2015 by sexton Quote Link to comment Share on other sites More sharing options...
ferretfixer Posted July 15, 2015 Share Posted July 15, 2015 It seems to appear a bit unlikely. but this DOES work (Well, It has for Me!) But the localised heat from a common CANDLE. Concentrated in the area you need heat. Has successfully loosened screws that have seized that I have encountered in weapons. I know the Ferret Carb is alloy (I know them inside out, after stripping & repairing quite a 'Few'! ) But it should take the localised heat from a candle flame with ease. If you can get access to the area you need to with one. It MIGHT just do the trick? What have you got to lose?................. Worst case scenario, the Carbs are available If you ask around. Quote Link to comment Share on other sites More sharing options...
Tony B Posted July 15, 2015 Share Posted July 15, 2015 If it's alloy, the other alternative is cold. Place in a plastic bag in the freezer for a few hours. What about dumping in it in an old pressure cooker for a couple of hours? Quote Link to comment Share on other sites More sharing options...
Diana and Jackie Posted July 15, 2015 Share Posted July 15, 2015 Hair dryer? heat applied very carefully (as its an aluminium alloy) and cheap spray oil usually frees things off in time too. Diana If it's alloy, the other alternative is cold. Place in a plastic bag in the freezer for a few hours. What about dumping in it in an old pressure cooker for a couple of hours? Quote Link to comment Share on other sites More sharing options...
Tony B Posted July 15, 2015 Share Posted July 15, 2015 Or a Freezer sparay. Thay are very useful especially with disimilar metals. Quote Link to comment Share on other sites More sharing options...
STIG Posted July 16, 2015 Author Share Posted July 16, 2015 Thanks for all advice,the problem is that the volume screw snapped on the tapered needle past end of threads no threads left in carb its flush with air passage so nothing to grip or turn,i can see end of needle as its the screw which has a hole on bottom face off carb which bolts to manifold,tried to use modified needle nose pliers to grip and push it back through hole when carb body hot but not budging..probably have to bite the bullet and get another carb in case cannot remove it and keep at this one dont like things beating me..wish i new how someone snapped it must of been a trained gorilla mechanic lol..anybody have a carb or know were i can get one please get in touch. ..many thanks..stig. Quote Link to comment Share on other sites More sharing options...
sexton Posted July 17, 2015 Share Posted July 17, 2015 (edited) Stig, I had a look at a spare carb. What surprises me is I would have expected the tapered needle tip to have broken off because someone bottomed out the screw too hard and the tip jammed in the metering hole. The two photos below show the screw screwed all the way in, with the tapered tip sticking ~1/8" into the passage, and the metering hole with the screw removed. But it sounds like the tip isn't sticking out into the passage like in the first photo? Does it look like someone sheared the protruding tip off trying to get it out? Pot metal has a higher expansion than brass so heating the area up with a propane torch should release the tip it but it sounds like you have no way to push or pull it out. What about drilling it out? I used pin gauges to measure the metering hole. It's 0.059", same size as a #53 drill bit. The bore of the thread leading up to the metering hole is 0.160". If you know someone with a lathe, they could make up a steel drilling sleeve with 0.160"OD and a clearance hole for a #53 bit in the centre. That would allow you to do some precise drilling. You could also use a #54 bit (0.055") to reduce the chances of opening up the metering hole. By the way, I was wrong before - the screws are brass. Malcolm Edited July 17, 2015 by sexton Quote Link to comment Share on other sites More sharing options...
teletech Posted July 18, 2015 Share Posted July 18, 2015 I don't know what the Solex carb body is made of but it's some kind of aluminum/zinc/tin alloy that is seriously dense and heavy. I thought the carb was cast iron when I first lifted one off. Get some liquid nitrogen, it's not that exotic or expensive, and shrink that pin down. or a chemical options: (some paraphrased from other sources) If the carb is aluminum and not die cast zinc alloy... If you are certain it is aluminum, you can use an oxidizing acid such as nitric acid and the brass will dissolve while the aluminum is passivated in strongly oxidizing conditions. You could try about 5 percent concentration of nitric acid. Don't use hydrochloric (muriatic) or sulfuric (battery acid). If nitric acid hard to come by so another approach is to set up a simple anodizing tank with a battery charger. There is lots of info on homebrew anodizing that will also dissolve the brass while not harming the aluminum. Strong aqueous ammonia plus reasonably concentrated hydrogen peroxide could work, both Cu and Zn forming complexes with NH3 while the H2O oxidises the elemental copper. If you use just ammonia it will dissolve the Zn in the screw (and the casting if it's an alloy with Zn in it so test a place that won't matter) and make it really weak and porous which could aid removal. Quote Link to comment Share on other sites More sharing options...
robin craig Posted July 19, 2015 Share Posted July 19, 2015 I am totally floored by the quality of the replies given to this thread by some very smart people, proves how valuable it is to have the forum Robin Quote Link to comment Share on other sites More sharing options...
STIG Posted July 20, 2015 Author Share Posted July 20, 2015 Hi all thanks for all your help i managed to get it out. .yippee. .i used plenty of plus gas for couple days to start then heat and some hospital forceps(i think thats what there called..locking tweezers )modified to fit in hole managed to move it enough to loosen its grip in in air passage then used very small blade screwdriver to push tip back through passage..now looking for new mixture screws if anbody has any or knows where i can find some..thanks again people. ..😊😊 Quote Link to comment Share on other sites More sharing options...
STIG Posted July 20, 2015 Author Share Posted July 20, 2015 Stig, I had a look at a spare carb. What surprises me is I would have expected the tapered needle tip to have broken off because someone bottomed out the screw too hard and the tip jammed in the metering hole. The two photos below show the screw screwed all the way in, with the tapered tip sticking ~1/8" into the passage, and the metering hole with the screw removed. But it sounds like the tip isn't sticking out into the passage like in the first photo? Does it look like someone sheared the protruding tip off trying to get it out? Pot metal has a higher expansion than brass so heating the area up with a propane torch should release the tip it but it sounds like you have no way to push or pull it out. What about drilling it out? I used pin gauges to measure the metering hole. It's 0.059", same size as a #53 drill bit. The bore of the thread leading up to the metering hole is 0.160". If you know someone with a lathe, they could make up a steel drilling sleeve with 0.160"OD and a clearance hole for a #53 bit in the centre. That would allow you to do some precise drilling. You could also use a #54 bit (0.055") to reduce the chances of opening up the metering hole. By the way, I was wrong before - the screws are brass. Malcolm [ATTACH=CONFIG]105996[/ATTACH][ATTACH=CONFIG]105997[/ATTACH] Hi malcom on my carb tip was touching otherside no gap between tip and carb..maybe had wrong screws in ?? Will investigate further. .many thanks stig Quote Link to comment Share on other sites More sharing options...
STIG Posted July 20, 2015 Author Share Posted July 20, 2015 Stig, I had a look at a spare carb. What surprises me is I would have expected the tapered needle tip to have broken off because someone bottomed out the screw too hard and the tip jammed in the metering hole. The two photos below show the screw screwed all the way in, with the tapered tip sticking ~1/8" into the passage, and the metering hole with the screw removed. But it sounds like the tip isn't sticking out into the passage like in the first photo? Does it look like someone sheared the protruding tip off trying to get it out? Pot metal has a higher expansion than brass so heating the area up with a propane torch should release the tip it but it sounds like you have no way to push or pull it out. What about drilling it out? I used pin gauges to measure the metering hole. It's 0.059", same size as a #53 drill bit. The bore of the thread leading up to the metering hole is 0.160". If you know someone with a lathe, they could make up a steel drilling sleeve with 0.160"OD and a clearance hole for a #53 bit in the centre. That would allow you to do some precise drilling. You could also use a #54 bit (0.055") to reduce the chances of opening up the metering hole. By the way, I was wrong before - the screws are brass. Malcolm [ATTACH=CONFIG]105996[/ATTACH][ATTACH=CONFIG]105997[/ATTACH] Heres pic excuse quality. Quote Link to comment Share on other sites More sharing options...
sexton Posted July 20, 2015 Share Posted July 20, 2015 Those look like the right screws. So someone screwed that one in so hard it bottomed out at the back side of the hole. Wow. I think those screws are supposed to have a rubber seal ring between the spring and the carb body (at least I have seen one set like that) which makes them so hard to turn you don't get a good feel for when the screw taper has bottomed out in the metering hole. Maybe that's why someone just kept reefing? The metering hole in the body may have been opened up by the force used, so get a replacement screw with a nice taper on it. A lot of them have damaged tapers from being screwed in too tight. Malcolm Quote Link to comment Share on other sites More sharing options...
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