Re: Octane's Fast and Furious Carb Cleaning

[leonardhcross]

In Octane's post from 2006, he shows a way to fill the float bowls with carb cleaner. His method was to "squat" the carbs, remove the vacuum chambers and spray carb cleaner down into the float bowls. If one is just trying to clean out the bottom end of the carbs, would it be simpler to drain the bowls and then re-fill the bowls with carb cleaner through the fuel supply line coming from the fuel pump? Would this accomplish the same thing?

[redglbx]

Len, that should work so long as none of the floats or needles are stuck. But personally I’ve never had any luck doing that and usually I still end up pulling and disassembling the carbs to get them clean enough to run correctly, so anymore I just start there .

Now I’m sure that someone here has probably done ok with that procedure but I’m not that lucky.

[toomanybikes]

In Octane's post from 2006, he shows a way to fill the float bowls with carb cleaner. His method was to "squat" the carbs, remove the vacuum chambers and spray carb cleaner down into the float bowls. If one is just trying to clean out the bottom end of the carbs, would it be simpler to drain the bowls and then re-fill the bowls with carb cleaner through the fuel supply line coming from the fuel pump? Would this accomplish the same thing?

I guess you could try it, but no matter what process is used, you'll still need to run compressed air through all the passages to make sure they are clear.

The effectiveness of a soaking approach would also depend on what you use for "carb cleaner". Some can be pretty tough on sensitive rubber bits, like the diaphragms.

I'm currently working on a set of 1100 carbs. I did a pass with keeping them attached to the plenum under the notion that they might not be that clogged. Nope. The assembly is currently apart so that each carb gets time in the ultrasonic cleaner. Especially needed with the pressed in idle/slow jets on the '81.

[robin1731]

In Octane's post from 2006, he shows a way to fill the float bowls with carb cleaner. His method was to "squat" the carbs, remove the vacuum chambers and spray carb cleaner down into the float bowls. If one is just trying to clean out the bottom end of the carbs, would it be simpler to drain the bowls and then re-fill the bowls with carb cleaner through the fuel supply line coming from the fuel pump? Would this accomplish the same thing?

I guess you could try it, but no matter what process is used, you'll still need to run compressed air through all the passages to make sure they are clear.

The effectiveness of a soaking approach would also depend on what you use for "carb cleaner". Some can be pretty tough on sensitive rubber bits, like the diaphragms.

I'm currently working on a set of 1100 carbs. I did a pass with keeping them attached to the plenum under the notion that they might not be that clogged. Nope. The assembly is currently apart so that each carb gets time in the ultrasonic cleaner. Especially needed with the pressed in idle/slow jets on the '81.

You did remove those pressed in jets to clean them correct?

[leonardhcross]

Thanks for the feedback. I will remove the carbs, disassemble, inspect, clean, blow out everything and reassemble. One last question. The carbs were rebuilt using Randakk’s kit and video this past winter. Will it be OK to reuse any or all of the parts that came in the kit?

[Track T 2411]

Thanks for the feedback. I will remove the carbs, disassemble, inspect, clean, blow out everything and reassemble. One last question. The carbs were rebuilt using Randakk’s kit and video this past winter. Will it be OK to reuse any or all of the parts that came in the kit?

It's been my experience that as long as the rubber parts haven't hardened or are misshapen, they can be reused. Careful treatment of the gaskets on removal will allow them to be reused as well, as long as they're not damaged. My 2 cents...

[gltriker]

*
*Post#7

Thanks for the feedback. I will remove the carbs, disassemble, inspect, clean, blow out everything and reassemble. One last question. The carbs were rebuilt using Randakk’s kit and video this past winter. Will it be OK to reuse any or all of the parts that came in the kit?

It's been my experience that as long as the rubber parts haven't hardened or are misshapen, they can be reused. Careful treatment of the gaskets on removal will allow them to be reused as well, as long as they're not damaged. My 2 cents...

+ 1 with Track T's observations and confirmation of Randakk's kit components' reusability

In Octane's post from 2006, he shows a way to fill the float bowls with carb cleaner. His method was to "squat" the carbs, remove the vacuum chambers and spray carb cleaner down into the float bowls. If one is just trying to clean out the bottom end of the carbs, would it be simpler to drain the bowls and then re-fill the bowls with carb cleaner through the fuel supply line coming from the fuel pump? Would this accomplish the same thing?

Regardless of utilizing either method to flush the carburetor float bowls, the float valve seat and its filter screen, themselves, will not benefit until they are completely removed ( as shown) from their carburetor body.
Many restrictions of gasoline inlet flow past the float valve needle and seat is caused by accumulation of contaminants (rust fines) around the seat's filtering screen - outside diameter.
Back flushing the carburetor body's *INLET FUEL PASSAGE* through a still installed float valve seat and its filtering screen element with brake spray and/or compressed air is pointless, at best.

* *Sometimes a float valve seat's filtering screen element is discovered to be altogether missing! *

*Note:*
Reinstalling the float hinge pin will provide a little more structural insurance against snapping off the float hinge posts while removing the float valve seat and its filter screen from their carburetor body.

*

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[attachment=0]20230723_123707 - coupled carbs #1 and #3.jpg[/attachment]

[toomanybikes]

I guess you could try it, but no matter what process is used, you'll still need to run compressed air through all the passages to make sure they are clear.

The effectiveness of a soaking approach would also depend on what you use for "carb cleaner". Some can be pretty tough on sensitive rubber bits, like the diaphragms.

I'm currently working on a set of 1100 carbs. I did a pass with keeping them attached to the plenum under the notion that they might not be that clogged. Nope. The assembly is currently apart so that each carb gets time in the ultrasonic cleaner. Especially needed with the pressed in idle/slow jets on the '81.

You did remove those pressed in jets to clean them correct?

I know this is a source of contention, but I did not remove the press in jets since I don't want to mange them. Instead I rely on the ultrasonic, compressed air, and systematically blocking outlets to ensure the passages are clear. I've done this successfully on other '81s.

[robin1731]

I guess you could try it, but no matter what process is used, you'll still need to run compressed air through all the passages to make sure they are clear.

The effectiveness of a soaking approach would also depend on what you use for "carb cleaner". Some can be pretty tough on sensitive rubber bits, like the diaphragms.

I'm currently working on a set of 1100 carbs. I did a pass with keeping them attached to the plenum under the notion that they might not be that clogged. Nope. The assembly is currently apart so that each carb gets time in the ultrasonic cleaner. Especially needed with the pressed in idle/slow jets on the '81.

You did remove those pressed in jets to clean them correct?

I know this is a source of contention, but I did not remove the press in jets since I don't want to mange them. Instead I rely on the ultrasonic, compressed air, and systematically blocking outlets to ensure the passages are clear. I've done this successfully on other '81s.

Sorry but you really don't get all the holes completely cleared that way. I've removed some after the ultrasonic cleaner and they were still very plugged. I don't know if you've ever had one of the pressed in jets out but those holes are small and placed where air pressure alone doesn't work very well.

It very easy to the pressed in jets out without doing damage to them.

[Track T 2411]

It very easy to the pressed in jets out without doing damage to them.
[/quote]

Just curious, is there a better way than the 'drywall screw' method?

[robin1731]

It very easy to the pressed in jets out without doing damage to them.

Just curious, is there a better way than the 'drywall screw' method?
[/quote]

m3 x .5 tap right into the top of the jet. Only need to go in a few threads. No drilling required. Then thread a screw into with a washer and a nut. Use the nut on the washer as a "press" on the carb to pull the jet out. It is in Randakk's tech blog someplace. Maybe even on here someplace with pictures.

[toomanybikes]

[/quote]

Just curious, is there a better way than the 'drywall screw' method?
[/quote]

m3 x .5 tap right into the top of the jet. Only need to go in a few threads. No drilling required. Then thread a screw into with a washer and a nut. Use the nut on the washer as a "press" on the carb to pull the jet out. It is in Randakk's tech blog someplace. Maybe even on here someplace with pictures.
[/quote]

And does that process then ruin the jet, requiring a replacement?

[Track T 2411]

Ah. I now recall Mike Nixon using that method...

[toomanybikes]

m3 x .5 tap right into the top of the jet. Only need to go in a few threads. No drilling required. Then thread a screw into with a washer and a nut. Use the nut on the washer as a "press" on the carb to pull the jet out. It is in Randakk's tech blog someplace. Maybe even on here someplace with pictures.

Thanks for the tip. At the moment I have confirmed airflow through all passages, especially the ones leading to the little outlets near the butterfly valve, so I'm not going to remove the press-in jets. Once it's all back together I'll use a heavy dose of Berryman's B12 to clear out (dissolve?) any residue.

[robin1731]

Just curious, is there a better way than the 'drywall screw' method?
[/quote]

m3 x .5 tap right into the top of the jet. Only need to go in a few threads. No drilling required. Then thread a screw into with a washer and a nut. Use the nut on the washer as a "press" on the carb to pull the jet out. It is in Randakk's tech blog someplace. Maybe even on here someplace with pictures.
[/quote]

And does that process then ruin the jet, requiring a replacement?
[/quote]

No