Carburetor study with microscope plus Smarter Every Day video
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bertsmobile1
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Total and utter crap
Get a # 65 micro drill and try to cut a B &S jet biger
If you press hard enough you will get 1/2 turn in and the drill will jamb and most likely break.
And you can drill a hole through brass with a wooden stick and some sand if you try for long enough.
If the debris in the jet is hard, then forcing it through with any blunt object can and will cause the debris to score the sides of the jet which is just as much trouble as enlargement or obstruction.
The idea behind twisted wire jet cleaners and cleaning with jet drills is to break away the debris then transport it down the tool through the flutes.
In order to CUT you have to have a CUTTING EDGE and that EDGE has to be SHARP.
Carbide is harder than wood and steel but try to push a masonary drill into a lump of steel, wood or even brass and all you are going to do is make a mess burn the wood and melt the brass .
Having tuned carburettored engine for better than 50 years I can saftely say you are talking trash
Firstly fishing line is fine for pushing rust or fine dust through a jet
But it will not shift varnish or corrosion debris
To cut a jet with an undersized jet drill is next to impossible unless you put it into some sort of machine
Jet drills are high strength boron steel very similar to a mower blade and quite flexible
They will follow the easiest path which will always be what is obstructing the hole, not the jet unless the drill has a bigger diameter than the hole in the jet.
Brass is not marshmello
Welding tip cleaners are FILES and they are designed to remove tiny bits of metal that have been blown back up the pipe & welded onto/ into the copper, corrosion debris that has melted into the copper , carbon deposits that have alloyed with the copper and fluxes that have solidified .
While they can be used to clean carb jets with they can & do enlarge the jets, particularly in the hands of people without the fine motor skills in their hands developed from years of carefully cleaning a jet.
Brass is used to make jets for one and only one reason
It machines very cleanly with the correct tooling so the sides of the hole are smooth enough not to cause interfearence with the flow of whatever is being metered through it.
BAck in the old days they used bronze and bronze requires honing to get the same surface finish even when machined fully submerged
So for the average mug at home then a set of micro drills is more than good enough provided they start with a small one then work their way up .
Your chances of cutting the jet bigger with a drill bit between your forfinger & thumb is a long way less than zerro where as the chances of distorting or enlarging the hole using a file is quite high
If you want to enlarge the jet in a controlled way then jet drills are the go
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Hammermechanicman
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While we all have our favorite method to clean jets. Some of which have been blessed by angels and others which will result in the end of life on the planet. One of the uses for the torch tip cleaners is to slightly open up the main jets on these new mowers that are so lean they surge. I know the hole is not perfectly round but the fuel molocules seem to get through just fine. I have fixed a dozen or so this way. EPA is probably in a panic by now.
bertsmobile1
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I do deliberately enlarge jets from time to time on engines where they are just running too lean
Had Titan which was blistering plugs till I took the left main jet out 2 sizes.
That took a long while to figure out and ultimately I had to use the colortune & camera to confirm my suspicion.
Had Titan which was blistering plugs till I took the left main jet out 2 sizes.
That took a long while to figure out and ultimately I had to use the colortune & camera to confirm my suspicion.
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was that a knock on the door, i heard?
StarTech
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Hammer, They are on their way for I am a dirty rat fink.
But seriously you do need to be careful cleaning jets. Here I use hand drill that came with my torch tip cleaning set. And are not the file type but is actual micro drill bits. I have broke them most cleaning my cutting torch tip. Now I need to get a new set for the torch work. I do keep torch and jet drill bits separate. I have since collect about half of the number bits for jet resizing here or just to check the size of new jets so I can create a jet size vs part number cross reference guide I use internally here. Since no one seem to able to help me with this it is done as I run across new jets. It beginning to become useful so don't need to resize a jet by hand but just the next size on my chart sometimes.
For those that use wire probes just know what you are doing as not all holes are though ones some have check valves.
Joe Kuhn
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How do you know this? I've not seen any metal on my spun wires. Will have to look closer and report back.
StarTech
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Even paper will wear stainless steel. I replaced enough paper guides over the years. Even the fuel can wear the jets over time.
Joe Kuhn
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I believe you are correct, but that kind of time is not a factor here. I'm just trying to get the crud out of the jet so it will stop surging after I put the carb back together. My metal cleaners did that for me per my son's microscope before/after views. We did NOT see any metal bits - and we looked closely, closer than you can see with your eyes because we were using a microscope.