Cleaning help needed.

[Marten]

I wrote about it in the project tread, but here is the short story.

Cbx 82, cleaned all carbs (by Mike Nixons book) it ran on 4 cylinders. No 2 and 4 exhaust are cold or semi warm compared ot the rest.

Cleaned carbs again, same result. Fuel in bowls, spark on all plugs. Plug on 2 and 4 look like new compared to the rest.

Read a few treads here and now wonder if someone have a tip on how to clean the 3 small holes "behind" the throttle plate? In the bottom of the venturi.

All jets are as far as i can see clean, but i will test the propane torch method on them.

Grateful for any input.

Thanks Marten

[Jeff Bennetts]

Marten, another way to test that all the passages are clear (after disassembly and cleaning them) is knowing where all the passages begin and terminate. The tried true way is to purchase the can of carb cleaner with highest pressure, Beeryman’s is a good choice. Take the red tube that comes with the can and shape it into a conical taper, sandpaper works, then insert it into the various passages and watch for the stream at the termination points.

I know this sounds like carb 101 but it works.

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[Marten]

Thanks! I will try it out.

[daves79x]

I use brake cleaner to test, cheaper than carb cleaner and works fine. Leaves less residue too. I think your carbs should be VB64. Easier to test than VB60. Screw a bare mixture screw into it's tower until it seats on the carb you are testing. This will force all of your test fluid out the 3 small holes in the carb mouth. Open the throttle plate so you can see and do as Jeff says, force the tip of the cleaner nozzle into the idle jet and spray. There should be a very strong spray out of the three holes. If not, you have something still plugged. If your carbs are the '82 version of the VB64, they have screw-in idle jets. The screwdriver slot makes it harder to get a good seal on the test spray nozzle. Taper it more and it will fit in there.

Also, make sure your air bleed hole for the main jet is clear.

Dave

[Jeff Bennetts]

This is a better cut away to go with Dave’s explanation.

To Dave’s point always spray off your disassembled carb, carb parts and chase the passages with brake cleaner after using the stronger carb cleaners, cleaner finish.

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[Marten]

It worked, thank you Jeff and Dave!

I turned the pilot screw to the bottom and put a few rounds of electric tape around the red tube to get a good seal around the inlet jet.
I was awarded with a good spray pattern from the bypass holes.

A also plugged the "bleed" hole on top of the carb to get moore pressure to the bypass holes.

Bleed hole for the main jet was also cleaned in the sam fashion.

With these tips and pictures and also by looking at the casting of the carbs i got a good idea where all passages go and how they interconnect.

It now runs, but the irony is that it was an sparplug wire error (made by you guessed it, me....)

My punishment for doing that error is to clean the carbs 2 extra times.

But i dont care, it runs and runs good!!

Soon more info in the project tread,

[daves79x]

Well, you know, you just can't take anything for granted. Everything you do has to be verified correct or you end up doing it multiple times. So glad that you have it pretty much sorted.

Dave

[Jeff Bennetts]

Good job Marten, you will be the one giving advice now!

[Jeff Bennetts]

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[Marten]

Good job Marten, you will be the one giving advice now!

Thanks alot for that!

Geat pics that really helps you understand how the carbs work.

Everyone that are about to clean there carbs should memorize these.

[Jeff Bennetts]

Good job Marten, you will be the one giving advice now!

Thanks alot for that!

Geat pics that really helps you understand how the carbs work.

Everyone that are about to clean there carbs should memorize these.

You can thank JR for making that particular cut away, it’s a great tool for anyone attempting to refurbish their carb set.