Weber idf cleaning and rebuild

Stuff I used:  Berrymans Chemical Dip, Gumout carb cleaner, little carb brushes, and a guitar string.

I have finally had enough of these carbs. So I thought I would go through the simple process I did for cleaning and rebuilding them.

I disassembled everything except for the throttle plates,  throttle springs and lever.

Berrymans is fairly nasty stuff, so I recommend  gloves and a mask, but more importantly do it outside.

It comes with a little basket for dipping the parts.

I started with all the small stuff – emulsion tubes, idle jet holders, etc. (Not the jets. I simply got new ones.)
20  minutes soak time was  enough, then follow it with Gumout Carb Cleaner . The Berrymans will leave a fine gooey film . On the larger pieces a toothbrush with the carb cleaner is a good idea.

Then the larger pieces : top section (float , needle valve and seats removed, only the cast aluminum.
And the bottom large pieces. ~ 20 minutes each followed with Gumout.

I bought all new jets, needles and seats, that little return valve on the bottom on the bowl (forget what it is called – pump exhaust?) …

After that I went at all the pieces with a set of carb brushes . The pump jet hole is pretty small, so I cleaned it with a .018 guitar string.

Now this part was interesting to me.

I then took the carb base and sprayed Gumout into all the small holes I could find. It was a good way to see what hole leads where. Spray a hole in the top and then seeing  the cleaner come out another hole in the bottom of the bowl gave me a much better idea of what goes on in the carb. (A lot better than trying to follow the book's description. I am gradually learning how these things work.)
But even better was seeing the cleaner come out of the hole on one side of the carb body but not the other. Finding those clogged passageways.

I did find a clogged Idle jet , clogged passage ways associated with the idle jets in the carb body, and a small crack in one of the jet holders….
I have been having problems with these blasted carbs since I got the car 3 years ago. They have been working OK, but they never felt quite right.
I always assumed something was varnished in the carb bodies since the car sat for so long unused in Miami.  And I was correct!

After all that , (about of day of work), the car runs better than it ever has.

Not a big deal. Wear a mask and gloves , and  do it outside.

Oh yeah. That blurry photo is a paper jig I made for measuring the float height and drop.


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Everybody always recommends the Tomlinson books, but I have found them to be quite nearly useless. A lot of lights went on in my head when I went through the same process you just did about 10 years ago.  The more I learned about these things, the more amazed I was at they worked at all, let alone as well as they do.

... and they do work extremely well when everything is clean and appropriately dialed in.

Again, most excellent. 

The slotted brass jet in the bottom of the bowl is the accelerator pump jet, which includes a ball check valve. The ball allows the pump diaphragm to compress the gasoline and send it up through the accelerator circuit.

I'm unsure why you bought new jets, cleaning them should be sufficient. Glad you found the blockage in the carb body though, that is a game-changer. Now it runs, imagine that.

I recently bought the Berryman dip can, and have been using it on internal engine parts: valves, keepers, springs, rocker arms. Then blast with carb cleaner, absolutely outdoors and WITH eye protection! I can recommend the Harbor Freight ultrasonic cleaner for carbs. The carb body won't totally immerse, but you can flip it over to get the whole thing. I use a 50-50 water and Pine Sol mix. Works very well. Rinse with clear water and definitely blow them out with compressed air.

Well done, Carlos! IDF's are great carburetors (such an improvement over DCN's, DCNF's and even IDA's) when everything is working properly and they're set up for the engine combo. It's amazing how when you spend time getting to know something like this that when you're finished it no longer seems so mysterious.

Danny, there is a bit more to the story of these carbs, but I wanted to keep it simple for anyone interested in cleaning theirs. 

I had filed the jets earlier trying to get the carbs to behave (and had some success too) but wanted to put the jets back to stock  numbers. The ac pump jet had been replaced when I rebuilt them using the "cooking with idf" upgrade from CB performance.  Again wanted to take the carbs  back to stock.

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Stan Galatedsnova
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