TOPIC:

Picked up some used 28mm pumpers off eBay and have dismantled them totally for rebuild. Soaked the carb. bodies in Berryman's carb. dip for several hours. When I originally pulled the carbs. apart, one of the slides ( # 1 ) was really stuck but came apart after soaking in Kroil for a while. Noticed that the slide was a little scratched. So after cleaning the carbs real well after the dip with carb. spray cleaner, # 1 slide is still really tight to slide up and down inside the carb. bore ?

I tried to using a brown scotch-brite pad on both the outside slide surface and carb. slide bore but still tight ? I even attached a scotch-brite buffing attachment to my dremmel and polished the carb. slide bore which helped but still the slide is tighter than I like but will move with a little persuasion from my hands to move it up and down.

There is no raised surface area on the slide ( #1 ) for it drops in real nice in carb. body # 2.

Is there something else I should use to relieve the bore a little in the carb. ( #1 ) to enable the slide to move freely ?

A polishing of the slide bore and slide with a light abrasive metal polish such a Solvol Autosol usually does the trick.

Not found in the US, origin from Germany. Any other metal polish recommendation ?

Blue Magic or Mothers Aluminum and Mag Polish should work.
Keep in mind that the carb body is pretty soft, so go gently there.

The slides have a coating that can be damaged by solvents or scratches. I'd check there first.
Steve

Steve, As I said earlier, the slide works fine in another carb. body, so I know it's not the slide that is causing the drag.

I had a set of carbs that had a small dent in one side. I used 600 paper on it and it worked. You might look for something like that.
Steve

I had some slides get stuck at WOT on a 2-stroke Titan. That's when I found out two strokes don't need an ignition system at WOT, because turning the kill switch had no effect on slowing the motor. A city block is very short when you find out the motor is more powerful than the brakes! Had to pull the choke to kill it.

Anyway the slide tube was out of round near the top, as if someone dropped the carbs. A pair of channel locks brought it back round and it worked fine after that. But I also polished the slide and inside because it did have some scuff marks.

Loudhvx, What polish did you use ? Pretty much agree that the inside of the carb. slide bore has to be polished a little more and trying to get ideas how to approach it .

That was 20 years ago, but probably Mothers with some super fine cloth to start with. The slides were anodized, if I recall, so if you go through that layer the aluminum will disappear quickly. But if you go through the anodized coating, you've gone way too far anyway.

Used a little Mother's Mag & Aluminum Polish on my finger and a rag. Already seeing a difference and the piston is moving easier in the carb. bore. Not yet there but better.

The slides on the OP's carbs are probably hard anodized. Removing the anodizing would be inadvisable.

Takes a very soft lead pencil and evenly coat the side of the slide top to bottom and all the way around with it by rubbing the side of the lead on the slide. Then insert the slide in the bore and run it up and down a couple of times. Remove the slide, and the high spot(s) in the bore should be very apparent. A polishing wheel on a dremel can then be used along with a mild abrasive to knock down only the high spot(s) without enlarging the entire bore.

Good Ridin'
slmjim & Z1BEBE