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I'm just about ready to join the "Junk the Rochester" club! I've never been able to get one rebuilt right yet. I've spent the last couple of days searching all the threads and watching all the videos, and they've been a big help. I'm hoping that a bolter can clear something up for me, regarding the accelerator pump. I've installed the new pump and when pumped it fills the discharge well, and assuming it goes from there into the "chamber" right next to it? Again assuming from there fuel travels up into the air horn. Assuming there is a plugged passage from the discharge well, and soaking is the only way to clean it up? Please help. If needed I'm working on Rochester B off a 53 235.

Soaking and air pressure is the way to clean every passageway in a carburetor. The problem is getting a dip type carb cleaner that actually works. The tree huggers and other environmental goofballs have managed to ban most of the good stuff years ago. I used to be able to soak a disassembled carb for 2 to 3 hours, rinse the parts well with HOT water, and use high pressure air and a needle-tip blow gun (150 PSI air) and get every drilled passage squeaky clean. Now virtually all of that procedure is illegal, or at least frowned on by OSHA! I usually soak carb parts overnight in the dip cleaner that's available now, and hope it softens the crud enough to blow it out!
Jerry

I realize their are a lot of bolters out there that HATE the Rochester "B" carburetor. My experience has always been good with Rochester carburetors from the model "B" to the Quadra Jet 4 barrels. Carburetor dip is your best friend! Disassemble it and let it soak to make sure it get really clean. Lay out the parts on a good work surface in the order they go back together. Check the bottom bowl for flatness and the air horn for flatness prior to assembly. a lot of the Rochester "B" carburetors have gotten warped over the years from over tightening the screws. Patience and attention to detail is needed to properly rebuild a carburetor. Some carburetors are more forgiving than others, but take your time cleaning it really well, blow out everything with compressed air with a nozzle, check for FLATNESS between the air horn and bowl, follow the rebuild directions and measure and measure again for all tolerances on the float, pump, etc. DON'T OVER TIGHTEN THE SCREWS!! Carbking may jump in on this to add anything I missed. Of course, your other alternative is to throw out the Rochester "B" and get a Carter to rebuild.

Here is my take on this for what it’s worth. I rebuilt all of my own carbs for years. Jerry is right, the dip carb cleaner we use to be able to get was unbelievable. Nothing crud related survived. That was the key to a basement rebuild. Clean clean and careful assembly. Now, we cannot get the good cleaner any longer. So that is one big problem.

On the other hand, the professional guys still have access to that stuff and more. Ultrasonic cleaners, chromate baths, wet and dry flow benches, the ability to r move the little lead or aluminum plugs in the carb to get all the passages clean, bushings on the throttle shafts if necessary, truing up of the surfaces if necessary. So I gave up redoing my own quite a few years ago. Rock auto sells a rebuilt B for like 110 with a rebuildable core in exchange, 205 without. I have purchased my last four or five carbs from them. They have some outfit in Canada doing them. Every one of them worked as it should right out of the box. It’s hard to beat for the price.

I play a 12 string guitar, whenever I change the strings, it seems I always poke a few straight into my fingers! One day, I though, small gauge stainless wire, hmm, and saved the extra length I clipped off to clean out small passages in carbs and other things. They work great, like tip cleaners for an oxy-acetylene torch but even smaller! You might get some pieces from a friend who plays guitar and see if that helps!

I'm probably going to be a minority of one on this issue. But I've probably done more carbs than most of you, Possible exception is Jerry. Rumors abound that he rebuilt the carb on the auxiliary engine on the Ark!

Personally quite happy that the old two-part hydroseal gunk is no longer with us. Yes, it did clean the carbs of grease, dirt, etc. It also removed the protective chromate coating that allowed deterioration of zinc alloy carbs, and it would attack the base metal on aluminum carbs. Many of the chemicals that we used to have, we are much better off without, especially in the hands on non-professionals. I almost lost a good friend that was too frugal to pay a professional to paint his Pierce-Arrow. I don't still remember how many weeks he was in the hospital, but that paint job was one of the most expensive on record!

We quit using the two-layer stuff decades before it was discontinued, simply because of the damage it caused.

For years, we would glass bead the castings, and then send them to various metal companies to have the correct finish reapplied. EXPENSIVE!

The real answer today is the ultrasonic cleaner and a really exotic chemical........................................................Dawn dishwater soap!

Run the ultrasonic wide open, and the heaters to about 180~185 degrees F. for about an hour. Sometimes takes more than one application after changing the water/Dawn solution.

And it will NOT remove the protective coating, so that does not have to be reapplied (unless it has previously been removed in the two-layer gunk!).

As Jerry mentioned, directed compressed air IN BOTH DIRECTIONS for all passage-ways while the casting is still hot from the ultrasonic. Remember goggles. Our maker did not give us two eyes using one as a spare! They work as a pair!

Never thought about guitar strings (but then I don't play the guitar). I have a set of orifice bits that I use for really stubborn passage-ways.

Jon.

There was a reason for that layer of water on top of the chemicals in that dip cleaner bucket- - - - -those fumes were downright nasty, and the stuff evaporated in a hurry if the water went away. We didn't pay much attention to the coating on those carbs- - - -good point about removing too much of a good thing!

The alcohol/hydrogen peroxide fuel we used in the race car would eat the bottom out of a float bowl if we didn't run the carb dry between races. The whole fuel system up to the carb was stainless steel- - - -8-gallon pony keg for a fuel tank- - - -and stainless tubing all the way from the tank to the carb. No fuel pump- - - -we used a few pounds of air pressure in the tank to push the fuel through the lines and topped off the pressure between races! That engine was just a few cubic inches short of 300, and it got 8 laps a gallon on a 1/4 mile track!
Jerry

Jon,
How do you heat your ultrasonic bath? Ours is small, 6x6x10, and has a water jacket but no heating element, just an inlet and outlet tube. Picked it up from a silicon chip maker that must have had a hot water source. Our vapor degreaser came from the same source and it cleans parts so clean that some can bond together with cohesion. Dawn detergent has put GoJo and other cleaners out of business in our shop.

On the ultrasonic bath.........there a dozens of units that are more or less just a vibrating vessel vs a true ultrasonic cleaner.........so your results vary widely.

One of many reviews :

https://www.pewpewtactical.com/hornady-vs-harbor-freight-ultrasonic-cleaners-review/

Evan - a long time ago, a really good friend suggested I acquire a good ultrasonic cleaner. Not really wanting to spend the many thousands of dollars then required for a made in the USA ultrasonic unit; I purchased one of the off-shore units from an ebay vendor for $600. Of course, the directions were in pictographs, and there was zero warranty.

I plugged it in, and stuck in a VERY dirty carburetor. SURPRISE! In about 45 minutes, that carb was virtually clean! Two carburetors later, the unit died! No return, no refund, I should have known better! My fault!

But the results WHILE IT WORKED were spectacular! The $600. was lost, but it paid for the test run! So started checking for USA manufactured product. Found a company in Ohio with a telephone number. Called the number, and got a technician/salesman who spoke English! He described their basic unit, but then described each of the options (heaters, rheostat controls on both ultrasonic and heaters, etc.). Ended up with a unit that is sufficiently large to submerge a complete Holley 4160, Carter AFB, Carter TQ, or Rochester Q-Jet, with the options. Unit cost then a little over $5k. They are probably cheaper now. That was maybe 10 years ago, and countless hours of use. One of the very best investments I made for the business. A home enthusiast probably can get by with a smaller tank (less expensive), but would highly recommend the controls and heaters.

Cleaning the entire carb before disassembly has several advantages: the obvious one is less dirt , but more important, the ultrasonic waves tend to break up corrosion bonds, and the carburetor becomes MUCH easier to disassemble.

After doing lots of experimenting, I found the Dawn (Simple Green, Purple Power, others) are not quite as good as the $30./gallon commercial stuff, but with a little extra time, do a good job and are much less expensive.

I run the heaters (remember, I have a rheostat control) at 185 degrees, and the ultrasonic generator wide-open for a 45 minute clean. Drain the solvent, flush, and do a second clean. Now drain the solvent, and flush with fresh water only. Time to disassemble.

Jon.

This is why doing a carb at home may not be the best call. I stick to my guns here, the days of dunking the carb in cleaner, and throwing in a kit, particularly when the carb is now 60 or better years old or older, and been through who knows how many basement rebuilds in those 60 plus years (or gas station quickies for that matter) are in my view long gone. it just seems a better call to have a professional do the job with all that they have available to them in terms of equipment and supplies.