Fuel System: Rust/Varnish carb bowl cleaners

[LeoH]

After dipping a BBR-1 carb bowl in ChemTool for 30 minutes, there still is a decent crust of rust or varnish in the bottom of the accelerator pump column and the fuel opening slit to its left and more of the bowl.
Are there any other cleaner processes that folks have used with gummy carb bowls successfully? I read about someone using straight PineSol for days soaking, for one instance and another non-carb chem substance I can't recall just now. I have a dental pick and some brass brushes to start scrubbing in the open areas as well, but I'd like to get the smaller passages as clear as I can.

[Dan Timberlake]

Several years back Yamaha's carb soaking cleaner had a pretty good reputation. Cleaning gum out of long-sitting bike carbs is pretty challenging.

[LeoH]

I'll look into that. I sprayed a healthy dose of carb cleaner to just rest in the bowl for tonight.

[altair]

Most carb shops use ultrasonic for deep cleaning, they come out like NOS. Unfortunately most carb cleaners do day are somewhat diluted to be "enviornmentaly" safe. A very strong solvent that is still available is MEK. I have used electrolysis to remove stubborn unwanted crud.

[LeoH]

Most carb shops use ultrasonic for deep cleaning, they come out like NOS. Unfortunately most carb cleaners do day are somewhat diluted to be "enviornmentaly" safe. A very strong solvent that is still available is MEK. I have used electrolysis to remove stubborn unwanted crud.

I wonder if the guy who rebuilt my Lark's carb might run this bowl through his cleaner for me? I'll have to ask, thanks for the idea.

[Warren Webb]

I'm tempted to try soaking in Seafoam.

[BILT4ME]

Why not buy bucket of Carb Cleaner from NAPA and drop the carb into it for a few days? I used to do that years ago. I bought a 2 gallon bucket of carb cleaner that came in a 3 gallon bucket. You rig a piece of wire on the part to drop in, then set the part into the bucket so the wire is still accessible, put the lid on, and walk away until you're ready to do something with it. It can sit in there for weeks if needed. On really bad ones, I would rotate the part every few days (right side up, upside down, left side, right side....)

If you can't find the buckets anymore, find a plastic bucket from Home Depot (or whoever), buy about 10 cans of carb cleaner, spray it into the bucket (being safe of course), then dunk it in and let it sit.

You can buy the environmentally safe stuff or the nasty stuff. I would do the nasty stuff because it usually works better.

[LeoH]

I have the bucket of Berryman's like you're talking about. If that's not a problem to leave it in for longer than the 30 minutes they recommend, I can certainly do that. It's really just the bowl piece that has the residue to deal with, the top and lower 2 pieces below the bowl came out clean enough already. I'll drop it back in the bucket this evening and leave it until the weekend. I did find a 3 pack of small metal toothbrushes this weekend in case there's more to remove after that.

[jg61hawk]

Clear ammonia will clean carbs better than anything I have ever seen or used. Costs nothing, and works amazing. Also a few drops in a gas tank of a lawn mower or motorcycle will clean as it moves through. It may backfire as it moves through, (like water would) but it cleans. This is the best cleaner I have ever used on old gas.

[jclary]

As has already been suggested, use only a solvent specified for Carburetor cleaning. What many folks don't know, is that the method of casting these relatively thin alloy components, leave them porous. To seal them from leaking right through the body, they are sealed with a chemical in a process called "sintering." This chemical is impregnated into the casting under controlled heat while in a pressurized vessel. While the chemical is impervious to gasoline, other solvents, such as lacquer thinner, MEK, etc. will dissolve the seal and your carburetor will be ruined.

I'd rather risk a bit of a stain remaining in the bottom of my carburetor bowl than have gas oozing out the side. Besides, if you can't flush it out with the proper approved solvent, and can't scrape it off with a dental pick...it will probably be a very long time until it grows enough to re-clog your jets.

[LeoH]

Thanks for the comments about old varnish stain in the bowl, I probably might have tried to get all of it, BUT, honestly, the varnish and rust in the accelerator pump passage and the narrow main passage in the middle of the bowl were what prompts me to want to get it cleaner than it is. The narrow passages with the metering rods to the opposite of the accelerator pump seem pretty clear at least. I also think I'll do the soaking one day at a time, then clean some more, then re-soak if desired.

[Frank DuVal]

To clean the outside and the bowls, I have used baking soda blasting. I have not had a leak problem, but I have done less than a dozen carbs this way. Lucky so far? The outside holds paint real well after this treatment.

To clean the inside passages, I still dunk them in the 5 gallon pail for overnight or so. Watch, as some of these cleaners (old type) will discolor the casting at the water to cleaner interface line. It can etch a line that is impossible to remove except by blasting. Make sure to submerge the parts completely in the old big container cleaners.

[53k]

As has already been suggested, use only a solvent specified for Carburetor cleaning. What many folks don't know, is that the method of casting these relatively thin alloy components, leave them porous. To seal them from leaking right through the body, they are sealed with a chemical in a process called "sintering." This chemical is impregnated into the casting under controlled heat while in a pressurized vessel. While the chemical is impervious to gasoline, other solvents, such as lacquer thinner, MEK, etc. will dissolve the seal and your carburetor will be ruined.

I'd rather risk a bit of a stain remaining in the bottom of my carburetor bowl than have gas oozing out the side. Besides, if you can't flush it out with the proper approved solvent, and can't scrape it off with a dental pick...it will probably be a very long time until it grows enough to re-clog your jets.

Yesterday I picked up a R-1 Carter AFB that I took to a local guy who loves working on old cars (and is very good at it). I had taken it to him a few days before we went on our chapter fall tour and he has assured me that he would have it back in time for the tour. Didn't happen, but for good reason. When he opened the carb it was a mess- full of rust and general crud. He showed me pictures of it as it looked when he opened it and I had to agree that it was a mess. Anyhow, his solution was to repeatedly soak it in carb cleaner until it came clean which took over a week of repeating.
My memory doesn't work very well any more, but I'm pretty sure this was a carb I took off a wrecked '64 R-1 in 1970. The car had been sitting in a wrecking yard for a year or so with no hood and no air cleaner. The engine had water in all cylinders so I'm sure the carb had seen a lot of water/dust and such.
Anyhow, when I picked it up it was absolutely beautiful. He has bead blasted it then clear coated it and put it is a zipper plastic bag. He said all I have to do is bolt it on and maybe adjust the idle and air settings and I believe him. He did a Stromberg for a friend and he didn't have to do anything to it other than bolt it on and start it up.
I guess the whole point of this ramble is agree that only carburetor cleaner should be used no matter how bad it looks

[LeoH]

That does seem to be the route to take. I looked at the carb last night after 24 hrs in the Berryman's and it's 80% better. I'm giving it a day to air dry and then I'll probably dip it again until a carb kit arrives. I am comfortable now ordering one, looking at the results of the overnight soak. My concern with the carb interior came after I only soaked the carb the label directed 30 minutes. Considering many of the carbs aren't 10+ years in need of soaking, I guess they get results from typical carb 'dirt' with the 15mins - 30mins they recommend.