REALLY dirty carb with stuck needle jet

I was able to find a set of carb bodies from which I need only the #4 carb because of a destroyed and unremovable pilot screw. They were cheap but are very dirty - like dark brown scale inside. I was able to completely break it down except for the needle jet. I worked on it first with penetrating oil, then it was in the carb dip overnight. I've been spraying it with carb cleaner and scrubbing it this morning, but it is clearly going to need something more than that.

I've read that boiling a carb in lemon juice can remove just about anything. Also, what about toilet cleaner? Has anyone had luck with either of these methods or maybe got some other secret weapon?

Not sure what to do about the needle jet yet. I've tried driving it out but I'm a little afraid of breaking the carb body. Suggestions?

Thanks!

 

I was cleaning my fuel sender last night with Alcohol. The rubbing kind 91% and all the junk came off with a qtip. So maybe drip some of that on there. Don't get it near the rubber bits though.

 

Try some Kroil. That stuff is amazing.

 

When cleaning, I had excellent results from boiling lime juice, but this was after everything had come apart. I have no idea how effective that will be for unsticking seized parts.

One tip: back in my bicycle mechanic days, when something refused to come out (aluminum seatposts in steel frames are the biggest culprit), we'd pour Coca-Cola into the frame from the bottom bracket opening and leave it overnight. No lie, this worked every single time we tried it.

 

I've used CocaCola (the regular kind) for cleaning many things from toilet bowls to jewelry. It's the phosphoric and carbonic acids that do the trick. If you put a dried wishbone in it overnight, ity's like rubber in the morning cause it eats the mineral & leaves the collagen.

Great for cleaning the oily gunk off windshields too. Otter be great for carbs...

 

I've had the thing boiling for two hours plus in a 4:1 water:lemon juice solution. Most all of the dark crud has come off, although it still will require a little bit of light scraping, I think. The needle jet is still unrepentant. I think the Coke trick is what I'll try next, mostly because I'm curious and it's cheap.

Before I do that, though, I'm going to post a couple pictures of this thing. Now that it's basically clean, I can see corrosion in the aluminum in several places that concerns me. The very top of the tube where the needle jet slides in is partially eaten away. That's probably part of the issue.

I'm not familiar with Kroil. If people think I should continue with this carb after seeing the pics, and if the Coke doesn't work, that's what I'll try next.

Thanks for all suggestions.

 

Man, when I get in close with the camera it really doesn't look too good. I'm not sure what would cause this. Do you think these parts of the carb sat in water for a long time? Nothing has been breaking off while I've been trying to drive that needle jet out so most of the metal is still pretty strong, I think.

 

Here is what I do. I use an m-5 screw that is about 3/4 inch long(the same size that holds the hats on,just a bit longer). It should screw into the jet. You can then carfully use a hammer to "tap"(pound) it out. As long as you get it threaded in a ways you should be able to "tap" it pretty good. That is what has worked for me many times in the past. Just don't hit the wrong thing.

 

Hate to suggest this but....
Another set of carbs may be your best bet.
But I'm not an exspert here.

 

I like your screw Idea xyxj650, I'll have to remember it the next time I take my carbs down for cleaning. I'm guilty of messing the jet threads getting them out. Just remember to use a screw with a head small enough to clear the locating pin in the carb body.

 

The screw idea did the trick. Thanks.

I know what you're saying, although I think everything will still fit and operate properly. It's kind of a bummer because the other three carb bodies in this set were all in much better shape. It's too bad I can't use one of those...or can I? I know that the outside fuel port would need to be plugged, but other than that, is there any difference? Could I use silicone as long as I didn't get any beyond the inner port opening?

 

For what it's worth, I decided to use one of the other carb bodies from the set I bought. Lot's of cleaning and boiling for nothing on the first one. Oh, well...

I checked to make sure that the throttle shaft and hardware all fit correctly. I'll need to plug one the of the fuel inlet ports since this is going in the #4 position. Other than that, it appears that the bodies are identical.

I then managed to break one of the ears that holds the float pin on the second carb I chose. Nice. Everything came off of the third one just fine and it's now in the dip. I'll update later.

 

For what it's worth, I decided to use one of the other carb bodies from the set I bought. Lot's of cleaning and boiling for nothing on the first one. Oh, well...

I checked to make sure that the throttle shaft and hardware all fit correctly. I'll need to plug one the of the fuel inlet ports since this is going in the #4 position. Other than that, it appears that the bodies are identical.

I then managed to break one of the ears that holds the float pin on the second carb I chose. Nice. Everything came off of the third one just fine and it's now in the dip. I'll update later.