Carburetor Float Needle and Seat Repair with Steel Ball

Carburetor float needle and seat repair method. Uses a steel ball, flat punch, and small hammer. Video also shows testing of needle and seat to be sure there are no leaks. ( Testing is important.) Method works for rubber tipped needles, too. Steel balls are available at bicycle shops and bearing houses, and using the proper type is important.
Testing shows a fixed needle and seat, but does not show other defects like swollen float from alcohol in fuel, or binding linkage and incorrect float level.
Please see my other video on gasket cutting using steel ball.
• Case Cover Gasket Cutt...
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[@flapjackson6077]

Thank you, sir! I have an 1989 KDX200 that my sin and i have been working on for 12 years. It’s always run great, but had leaky carb issues. Two years ago we were about to buy a new carb but my son ran across your video. We bought some ball bearings, and although the one we used was just a little larger than you suggested, it worked!!!! We were stunned, amazed, and very happy. That was two years ago. Thanks to you, we’re still using the original carb. No leaks. Runs like a champ! He’s gonna be running it in a two hour amateur race in June. Thank you, my man! It works!

[@alankey9741]

Thank you. I have had so many (bike) carb float problems over the years and this is GOLD! You just fixed my Outboard! For others: For small Tohatsu/mercury 2 strokes, you need a 2mm ball bearing. You are a gentleman and a scholar. :)

[@Adventurepilot70]

I am glad it helped someone out. Thanks.

[@Mowtivated1]

I do small engine repair for a living Absolutely Incredible video

[@tasquill]

Thanks to all old timers and their old timer tricks....may the spirit be passed on ad infinitum!!

[@DudeGuyWho]

Totally what I was thinking.

[@TonyGingrich]

Even though this has been out a few years, I think it's still worth a comment. Overall, it's an excellent fix for a part which otherwise needs replacing. To be clear: the seats almost never go bad, though they do tarnish and accumulate filth. But unlike the needle, they are thicker metal and do not suffer significant force. The needles are the failed component when you see that scarring. The ball bearing trick is stretching the seat orifice uniformly. That results in a wider opening, allowing a "fresh" unscarred portion of the needle to be the new sealing surface. So long as you don't stretch the orifice wider than the needle cone--and that the new point of contact on the needle is smooth--this trick has the same effect as replacing with a new needle and seat. It should be noted: this can only be repeated a limited number of times before there's no way out of outright replacement. But also a word of caution. Be sure to check your float alignment afterward. This will cause the current adjustment to close the valve at least a slightly higher float level. That can put you at risk of flooding. Readjusting the float will prevent that.

[@DudeGuyWho]

Excellent reminder to look into float adjustment!

[@bartdevreese382]

thanks for the useful video buddy, I have a Keihin 4 cylinder carburetor with a fixed seat for the float needle and this really helped me, I had been struggling for a long time.

[@Adventurepilot70]

Glad it helped

[@smellbag]

Thank you sir, a simple , quick solution for a common issue.

[@donaldmatthies6026]

I actually did this on a 1988 force 50hp outboard carburetor, like the guy said it was done out of desperation because I couldn't find the part I need, it works really well! Thank you for taking the time to make a very informative video.

[@Adventurepilot70]

Thanks for sharing

[@realpremier]

You are a boss! Works perfekt, tried to grind the valve in with a drill, didn't work so good. This method is killer, thanks a lot! 👌👌👌👍👍👍

[@lesroberts2244]

Brilliant, yet so simple, sir I take my hat off to you. Regards from North Wales UK.

[@rayneandersen4509]

I'll be damned. 97 CBR #4 carb leaked like a sieve filling engine with fule. Was at the end of my rope and bought new carburetor body only to be delivered the wrong carburetor. I searched the net furiously to find anything I could and found nothing. Was about to give in and set the bike on fire but then saw this video today. I did this. I went to Ace hardware bought a steel ball bearing, put it in the seat and smacked it with a hammer and I'll be damned if it didn't completely change the seat and sealed the needle up then I tested it in the water and no air at all. I will install it on the bike tomorrow and see if it really really fixed it. Thank you so much for posting this video. Stay safe up there!

[@Adventurepilot70]

Glad it helped you. Like you, it was really an act of desperation. I should think that doing this would ruin the seat, but it has worked perfectly for me every time I used it.

[@rayneandersen4509]

@@Adventurepilot70 well I took me a while but I finally got the carbs back on and I'll be damned again it worked I told a bunch of people and nobody believes that but seeing is believing of course now fuel is leaking like a sieve out of my air solenoid. This is the second time it's done this and I guess I don't know how to fix it. Happy but sad! Hey thanks again for posting your video.

[@nickcapozzoli]

Hell yeah! I used a 4.5mm steel BB gun round and it worked like a charm, many thanks for the insight.

[@guillermo851]

Congratulations, everything has a solution for brilliant minds

[@restoreamerica1222]

Man im glad I followed my instincts and watched your video....ive been struggling to find a repair kit for a mikuni #26 B7540 and nnnoooo body has been able to help...im gna utilize this!!! THANK YOU MAN!

[@dw4940]

What machine does that carb go with? Everyone online forums recommend Shindy rebuild kits-made in Japan..

[@cayminlast]

Awesome tip, thanks for figuring it out.

[@hmroa3056]

Amazing! Awesome information, thank you Sir.

[@AaronRiegel]

What a great trick, putting this one in my arsenal

[@jefflink4671]

Excellent I will give this a go on my snowmobiles mikuni carbs Recently had trouble with one, ran fine the day before, overnight gas leaked out enough to flood and even put a small puddle below sled. Mine needle has the vitron tip and could see a minuscule witness line on it. Great idea on the water test. Thanks so much.

[@billybobbubbawubba9457]

Mikunis have replaceable needle seats.

[@Ryan16Deguzman]

Amazing! I love learning little tricks like these. Thank you for sharing your knowledge

[@niconine268]

Thankyou very much. This is perfect. So good to know this method for my carbs should I need it at any stage

[@bunbunoneng8049]

thank you sir , its work .. i try with loose ball for fix mikuni ninja 250 R . and now carburetor very normaly.. 🙏

[@ghostukvibe7224]

No way ! I’m trying this right now ! Was going to order a full brand new carb for 60 pound cause of this problem and I’m going to try it and let you know , my bike floods out at the moment so we will see if your magic works 👍🏻

[@Adventurepilot70]

Be sure you use a hardened and ground steel ball.

[@db3170]

Brilliant!!! Thank you for sharing

[@danimarie5583]

You're a life saver! I thought I'd never get this bike fixed. Thank you!

[@Adventurepilot70]

I am happy it worked out for you. It seems like it works most of the time, if you do it correctly. Happy riding.

[@slickricktheruler]

Awesome fix! Thank you for sharing.

[@Adventurepilot70]

Glad it helped

[@billybobbubbawubba9457]

Gdammit, after going round and round with KDX Keihin doing all the usual q-trip-abrasive crap, adjusting the float many times, I did this. It WORKED!!!!! Thanks.

[@cr250r9]

Dude, I laughed when I saw this comment because I’ve had an 89 KDX for about 10 years now that has always had a leaky carb. Went through the same exact stuff with float, q tip, and it’s been rebuilt multiple times and always still leaks. I’m interested to see if this will fix mine too.

[@Adventurepilot70]

Should work if you have an accurate ground steel ball.

[@cr250r9]

@@Adventurepilot70 I’ll be sure to grab a ground steel ball and a brass punch. I’ll let you know how it goes! Either way, great video👍

[@Adventurepilot70]

@@cr250r9 Just be sure to test it as shown, to be sure the needle seals tight.

[@stevekerns3468]

Thanks for a great trip I tried your fix and it worked great. Thanks

[@Adventurepilot70]

Thanks for letting me know. Glad it helped someone.

[@semisane653]

your basically flaring the part where the needle sits,opening it up for a better sitting of the needle. that was brilliant!!! are you a pot head as well?? thanx for the tip my brother.

[@dw4940]

Why would you think hes a pot smoker, just curious? I grew for 22 yrs and he doesnt strike me as a pot smoker... but I could be wrong.

[@Indian56671]

Great work well-done great work Thanks 👍👍

[@molagbal4093]

i applied the same method but with a punch small enough to just fit in the hole. leak fixed, many thanks

[@bipedalbob]

Should be the same effect, could be easier than trying to hit a tiny bell with a flat punch, just stick your point in the hole and give it a wack.

[@dw4940]

I was thinking same thing, use a center punch..

[@roybulcock8116]

@@bipedalbob If the centre punch has been sharpened at any time, this may not be as good as the hardened steel ball.

[@bipedalbob]

@@roybulcock8116 the tiny steel ball is probably better it's just getting one is difficult, I ended up polishing mine and that worked, only because I ordered a new complete carb on Amazon for $17 Canadian, took a couple months to get it and then didn't need it but it's cheap karma insurance, if you have it you won't need it .

[@strawboss59]

I'm going to try this. The manufacturer of the carb I'm rebuilding stopped supplying replacement valve seats, that really ticked me off. Thanks.

[@gringoanon4550]

Bloody amazing thanks for the tip.

[@isaacpaulsen1158]

Great stuff thank you.

[@mikeday9699]

Excelent, Thank you very much.

[@BMRStudio]

Wow :) Thank You sir!

[@vikaswadekar5632]

Good job done 👍

[@tomlibero3780]

Very Helpful! Thx!

[@brycechadis3610]

Awesome dude I'm also a pilot and a bike tech

[@forresttaylor6849]

Brilliant!👏👍

[@bipedalbob]

Brilliant, if it's already broke and this cost nearly nothin to try to fix it, and he even showes you how to check to see if did. Gonna try rhis on my snow blower carb.

[@Adventurepilot70]

It might take a pretty small ball, but you can find them at bearing shops or online.

[@bipedalbob]

@@Adventurepilot70 gonna start looking tomorrow, a ball about 1/2 to 3/4 bb diameter would be just right.

[@SlowBrow]

been very helpful...tx

[@peterboytchev6899]

Are you are smart that is a good good idea thanks so much

[@russbilzing5348]

I cannot thank you enough!

[@backncardr]

Steel ball worked for me after seeing this vid. ATV leaked out more gas than it burned. It would drain the tank if I fergot to turn off the fuel cock. Yup crankcase had to be drained each time too of gas. 2 stroke Polaris. Dealer wanted like 55 bucks for a new combo and 50 miles away ugh. Glad to see this video and save some hair I don't have much of from pulling it out over this leak.

[@Adventurepilot70]

I am glad this method was a help to you. I hope it can solve the problem for a few enthusiasts who cannot get new parts, or are too expensive. My own carbs leaked very badly, so I figured I had nothing to lose by trying this out, and to my surprise it has worked every time I tried it. Like you, I don't have much hair.

[@reioXyhi]

Excellent idea and thanks for video. I think a drill from your drillbox what fits nicely in the hole and the hammer punch on the sharp end of the drill. And size of ball maybe diameter size of the valve cone at almost the widest diameter. (80-90 % from the tip of cone). How about that?

[@RY4NP]

Wow, very clever

[@geraldpichette5886]

Great information TANKS

[@aterack833]

i believe you are basically forging it to the shape, something the exact shape of how the seat is meant to be might work also, and give something to pull it back out by, this would force the small scratches and micro bumps and stuff to fill and anything raised to flatten, if you see scratches on the needle they were likely caused by those things, i want to try this on a set i have but i already used the polishing method, though they seem to keep getting a buildup

[@mbtee]

I found this is very interesting I investigated it and found that these Chinese carburetors the seat is drilled from the outside leaving a bur on the inside causing these needles to leak and but using the steel ball it gets rid of the bur

[@billybobbubbawubba9457]

I went through then same thing. Fixed my OEM this way. Will give noodles the same treatment.

[@DudeGuyWho]

SO GLAD you mentioned this! Had no idea and don't think I'd have considered this.

[@plusblood5101]

Super genious You are super smart Gr8 idea Thanks

[@TuttleScott]

I've got a four wheeler out in the building right now with a leaky float I'm going to give this a try. not sure if I have any bearings that small but I do have some BBs. if it doesnt work I'm going to try over drilling the hole a smidge to re-round it and let it contact the needle where its not worn.

[@Adventurepilot70]

I think you should use a steel ball that is ground. A BB is soft and not heat treated. It is also not very round. You can buy the steel balls at any local bearing supply shop or a bicycle shop. You might try Ebay or the internet as well.

[@TuttleScott]

figgered you were right about the BB so I lightly reamed the edge of the seat with a small drill bit and polished it a bit with qtip, valve grinding compound and drill. I also replaced the o-ring on the seat. seems ok now. cross my fingers.

[@srnunan4783]

It works because metal to metal fluid seals like this rely on a single point of contact, a circle where it touches between the seat and needle, the surfaces dont have to be matching angle etc, infact a large contact area is more prone to a small mismatch somewhere which leads to a leak.

[@alm4737]

Brilliant. Thankyou.

[@russhoward1]

Fantastic thankyou

[@DudeGuyWho]

Thank you for sharing the wonderful idea. I love these innovative do-it- yourself fixes. I did notice that when you put the carb back in to test it, you didn't submerge it like before. If you only place part of it (not fully resubmerging again) back in the bucket of water... how can you know the test is good before putting it back on the bike?

[@Adventurepilot70]

The needle and seat were submerged, and that was what I was testing. Had sort of a short piece of tubing to blow in.

[@doronron7323]

Yup, good idea! My 1950's BSA manual points this out for the sprung ball oil none return valve. Nothing new, just forgotten wisdom.

[@juddbelue1283]

Worked for me. Nothing else worked on a little Yamaha breeze. Was about to order a Chinese carb…

[@Adventurepilot70]

That is great to hear. Good luck with it.

[@pnh6999]

AWESOME!!

[@Adventurepilot70]

Thanks!!

[@socialdestroyer4112]

I think your bearing is busting through the buildup on the brass mother's car polish on a Q-tip in a drill works great

[@josepeixoto3384]

great! next time i need that,i'll try with the fine valve grinding compound on a q-tip; great analysis,and great tip; i´ll add that the steel ball method, may even correct fine scoring lines on the seat,due to erosion/material defects,but it's diameter is key.

[@Adventurepilot70]

I tried the polish on a Q-Tip idea on a couple of other carbs, but couldn't get it to seal. I admit that using the steel ball was an act of desperation, and it surprised me that it worked out for me. Using the steel ball should be tried, only if you don't know what else to do. If you test it and it still leaks, you can hit it again. Just be real sure the ball is centered on the hole.

[@socialdestroyer4112]

Don James awesome man glad to have that advice

[@pintail120]

@@Adventurepilot70 I think polishing is a bad thing after watching this video, you want a sharp edge, polishing removes that sharp edge ? Maybe constant movement of the needle on the seat removes that sharp edge over time ? Using the ball to peen the edge it then makes it nice sharp and reinstates the integratity of its shape

[@jaimeramirez4664]

Thank you... J

[@chrisstratton3430]

Thank you

[@Adventurepilot70]

You are welcome.

[@plusblood5101]

Awesome

[@stevensawyer2489]

Thanks very much for this tip. My sled filled up with gas,it don't have a shut off. Duz now & ill be pulling carbs out tomorrow.

[@alexruwhiu7384]

Wow - great alternative to reaming and polishing out a seat because you're not removing any metal and the seat/float remains at the same height - haha loose balls and stuck balls can give you big problems tho

[@caluzzucarrazzi5549]

this was an outrageously good video - where in the world did you find a little brass punch like that designed for tiny bearing balls?!

[@Adventurepilot70]

I got a set of them from Harbor Freight. A steel punch will work, but might put a flat spot on the ball.

[@jeffmee763]

Thank you for your video I've got a 2mm 2.5 3mm one which one do you thing is the best one to use in my CV carb thanks Jeff in UK.

[@Adventurepilot70]

Largest one that will fit.

[@jeffmee763]

@@Adventurepilot70 thank you great trick.

[@jeffmee763]

@@Adventurepilot70 Thanks.

[@joet6990]

Who can help me with this? I have a 2004 blaster that wouldn't stsrt without stsrting fluid. I took it apart and the float needle was stuck in the thing it slides up/down in. Would that cause it to Not start? I broke the tip of it so I can't toss it back together until the rebuild kit gets here, would it start with the tip being broke or no?

[@bipedalbob]

Nope it won't now you probably need a new carb body to go with your rebuild kit.

[@geraldpichette5886]

Thanks again on my way to friends he goings to be happy I started doing carbs 1978 and love this fix the last two months day and night carbs I'm laying in bed smelling like old gas and carb cleaner right now 10.00 PM was going to shower I won't be able to sleep goings to get that leaking Honda I gave up on thanks so much goings to shoot your clip to gus I been doing this with for decades yeah

[@114wildfire]

Hi, Sorry but I’m not sure what was achieved by what you did. You put a ball to cover that hole, then you punched the ball, then removed the ball. What did that do exactly and why did it fix the problem? What does it mean by “peen” that hole? Like you said in the video ?

[@Adventurepilot70]

Hi, Mike. What I achieved was it quit leaking as shown in the video. Why it did this, I don't know. It seems a terrible idea, and if someone asked me about doing this, I would say it would ruin the seat, as the seat would not match the needle. This was an act of desperation, as I had a carburetor body that has a non-removable brass seat. The choice was to buy a whole new carburetor body or try to find a new carburetor. On very old machinery, this can be difficult.. I have used this method to fix 8 or 9 carburetors since using this method. Twice I had a great improvement in leakage, but was not perfect. I repeated the procedure and got perfection. I always test as shown to be sure no air leaks. I always use a hardened and ground steel ball. ( Available from bearing supply shops. ) I tap it very lightly with a very small hammer. If you can get a new needle and seat, do that. This is something to try as a last resort. Just because it worked for me does not mean it will work for you, as you might do something different than shown in the video.

[@dimasuracalvinjake683]

You must be Ridiculously stupid

[@BLarncris]

There are Angels among us...

[@gerdaanwisse4746]

i have try it whit walbro hda carberator alu casting no result. i have tryed with 3 different balls. wat els can i try??

[@skyb8687]

Man u probably already figured it out but I just polish where the needle seats,I've used a really small (dremel) brass wire brush,or 0000 steel wool,or I'll take like 3 q tips and put them in the chuck of a drill and polish inside

[@deeboy1321]

My fuel pump wont prime when hoses are connected and bike won't start. If I take the hoses off it primes. Filter is good was told carb is stuck. Please help

[@Adventurepilot70]

Take the carb off and remove the float and needle to see if it is stuck.

[@dw4940]

Excellent! Gonna try this seeing that the little Phillip's head screw is rusted -stuck, holding seat in place...they should have used stainless steel cos of it rusting and that rusted metal powder could plug one of the tiny.holes such as the pilot jet!

[@Rameus]

How are you determining what size ball you use?

[@Adventurepilot70]

It seems the exact size is not that important. Use the largest ground steel ball that will fit into the hole where the needle goes. If you use a ball that is too small, you could get it stuck in the inlet hole, and might have a great deal of difficulty getting it out.

[@Rameus]

Don James, I was going to use a steel BB from my old red Ryder BB gun. Didn't want to mess the seat up because my seat isn't removable.

[@Adventurepilot70]

Don't use a BB. They are soft and not heat treated. While a BB might be the right size, they also are not centerless ground, so they are not very accurate. The ball is going to peen the valve seat.

[@Rameus]

Don James ok thank you for the advice. My uncle owns a excavating company. I will scour his shop for a real ball bearing.

[@terrytalbert3606]

It rounds the seat back out

[@tomrc4328]

You are making the hole round, if it wasn't already, and you are creating a sharp edge for the needle to seat on. The worn edge having a rounded profile provides too much surface area and the pressure pushes past the sealing area. You want the needle seat to have a sharp edge, and that is what the ball is restoring when you hit it. That is my understanding and experience.

[@t_petya9382]

Hi! My results about this procedure on my Yamaha Tmax... 1st. I used a 3mm ball, but the carb was still leaking. Than I used a 4mm ball and it was succesfull (at this moment). After riding 200 Kms, the carburetor is overflowing again. :(

[@Adventurepilot70]

Testing as shown shows the needle and seat work, but does not check other problems, such as swollen or sunken floats, binding or incorrectly adjusted linkage.

[@t_petya9382]

​@@Adventurepilot70 You're right. Please tell us your experiences about how many milles can you ride your bike after this procedure please?

[@Adventurepilot70]

Airplane and motorcycle are still working fine.

[@waynewootton5385]

whats the name of the carb.

[@Adventurepilot70]

This one was a Mikuni from a Yamaha R5C if I recall correctly.

[@brandenrickel1192]

I have a wr250f and it's flooding and leaking gas from the nipples of the carb this would work it's $1600 for a new carb

[@Adventurepilot70]

I can't say for sure, but if your carb is leaking, what have you got to risk? Just be sure to use a hardened and ground steel ball, and TEST for leakage before you assemble everything.

[@henrysmith8012]

I polish my seats with Q tip and valve lapping compound.

[@terrytalbert3606]

Most kits u replace the seat.

[@Adventurepilot70]

It seems you miss the point. This is a solution for those that cannot get a new seat, or that don't have a replaceable seat.

[@xplane7523]

Float O-Ring replacement on Mikuni BST33: kzbin.info/www/bejne/paDQcpmnaZiDqa8

[@gordonanyhowe3081]

8+ minutes of talking about ball bearings and describing what you are going to do in what should have been a 2 minute video. Helpful idea though.

[@Adventurepilot70]

I am sorry it took up too much of your time. I feel the type of ball used is critical for success using this method, and using unhardened and ground ball may not give good results.

[@maryconrad3168]

I liked your video but in all respect it’s a bit tedious to watch. Just to much unnecessary info, like discussing the package of bearings and how much they cost, etc, etc, etc. all that just makes one want to yell “ get to the procedure”.

[@Adventurepilot70]

Sorry you didn't like the video, Mary. I will try to do better in the future.

[@brianj1204]

@@Adventurepilot70 yes but some people may need more info. Not everybody knows or understands how a carb works. This is a great idea. I will be trying it as I have one out four carbs just being a pain in the butt. It's an old Yamaha FJ1200.

[@Cil3kes]

helped me a lot... my needle was stuck and carb was overfloating ,,.fixed now