1978 USA import CB550 K4 PD46C CARB

[Brian Cairns]

I have got my self confused just wondering can you please check the picture and my identification oof carb parts:
1. air mixture screw (1 1/2 turns out)
2. Slow jet/pilot jet ?
3.main jet & emulsion tube

If identifications are correct, how do I remove slow jet, as I want to check sizes. Should be 42.
I checked main jet sizes, one was 98 and the other 3 were 90's. Obviously should all be same size.
Also what position should jet needle be? I am getting conflicting information on the web . Some say the needle can't be adjusted on the PD46C carb and some say they can?

Thanks in advance
Brian

[Oddjob]

Identification is spot on. Take the mixture/air screws out and make sure they are intact. IIRC they have a really fine needle on the end of them, if you screwed them in too tight it would shear off in the carb body, there is also a spring a washer and a really small oring fitted on it. Spring on first, washer to stop the spring cutting into the oring, then the oring. You may need to fish it out of the hole.

The slow jet looks to be a push in fit, been many many years since I mucked with a set of those carbs so can’t say for sure how it comes out.

[Brian Cairns]

Identification is spot on. Take the mixture/air screws out and make sure they are intact. IIRC they have a really fine needle on the end of them, if you screwed them in too tight it would shear off in the carb body, there is also a spring a washer and a really small oring fitted on it. Spring on first, washer to stop the spring cutting into the oring, then the oring. You may need to fish it out of the hole.

The slow jet looks to be a push in fit, been many many years since I mucked with a set of those carbs so can’t say for sure how it comes out.

Brilliant! thanks so much.

Brian

[Brian Cairns]

Identification is spot on. Take the mixture/air screws out and make sure they are intact. IIRC they have a really fine needle on the end of them, if you screwed them in too tight it would shear off in the carb body, there is also a spring a washer and a really small oring fitted on it. Spring on first, washer to stop the spring cutting into the oring, then the oring. You may need to fish it out of the hole.

The slow jet looks to be a push in fit, been many many years since I mucked with a set of those carbs so can’t say for sure how it comes out.

Brilliant! thanks so much.

I discovered that the slow jets are correct size ( 42) . They are push in and apparently designed never to come out! I won't mess with them.
I looked at airscrews , no washer or spring in any of them. Hopefully when i redo carbs the bike will run a lot better. The previous owner seems to made a hash of them. Bike hard to start and can't get over 65 mph......


Brian

[Bryanj]

The slow jets DO need to come out as bothe the jets and passAgeways block for a passtime, grip firmly with vicegrips and pull and twist at same time.
Refit with light tap from soft hammer.

EDIT

You can get replacements from Sirius Consolodated in canada along with the O rings and washers for the mixture screws but their website is a nightmare to navigate

[Brian Cairns]

The slow jets DO need to come out as bothe the jets and passAgeways block for a passtime, grip firmly with vicegrips and pull and twist at same time.
Refit with light tap from soft hammer.

EDIT

You can get replacements from Sirius Consolodated in canada along with the O rings and washers for the mixture screws but their website is a nightmare to navigate

Ok will give it a go.
Cheers
Brian

[SteveW]

I pulled the ones out of my PD50’s by heating carb body with a hot air gun. Wrapped a pice of rubber tube around the jet and it pulled out pretty easy.

[Brian Cairns]

I pulled the ones out of my PD50’s by heating carb body with a hot air gun. Wrapped a pice of rubber tube around the jet and it pulled out pretty easy.

Cheers

Will try that

Thanks'

Brian

[deltarider]

A few pics that may help.

[Oddjob]

I did think you pulled them out TBH BUT I wasn't about to say grip them with pliers etc as it sounded a little brutal to me and likely to mark the outer part.

Glad to see my memory was right about the air screws, exactly as I remembered them, not bad for 40 odd years ago.

[K2-K6]

Probably not worthwhile just for a single job, but these Kniipex twingrip pliers have a "bore" in the nose that's particularly effective in gripping a cylinder https://www.amazon.co.uk/KNIPEX-82-01-200-atramentized/dp/B09FPZPY96/ref=asc_df_B09FPZPY96/?tag=googshopuk-21&linkCode=df0&hvadid=641638718575&hvpos=&hvnetw=g&hvrand=6235607503535841976&hvpone=&hvptwo=&hvqmt=&hvdev=t&hvdvcmdl=&hvlocint=&hvlocphy=9045915&hvtargid=pla-1640846664898&psc=1&mcid=e02a7d1495603634ba0636b3393dbad5&th=1&psc=1

Obviously a limited use here but very effective. Usually when you turn to get the pliers out something has failed, stuck or broken, these really do grip like hell to avoid slipping and seem a good addition to a toolkit.

[McCabe-Thiele (Ted)]

Neat looking pliers.

[Brian Cairns]

A few pics that may help.

Great !

Thanks
Brian

[Brian Cairns]

I did think you pulled them out TBH BUT I wasn't about to say grip them with pliers etc as it sounded a little brutal to me and likely to mark the outer part.

Glad to see my memory was right about the air screws, exactly as I remembered them, not bad for 40 odd years ago.

Cheers

Brian

[Brian Cairns]

Probably not worthwhile just for a single job, but these Kniipex twingrip pliers have a "bore" in the nose that's particularly effective in gripping a cylinder https://www.amazon.co.uk/KNIPEX-82-01-200-atramentized/dp/B09FPZPY96/ref=asc_df_B09FPZPY96/?tag=googshopuk-21&linkCode=df0&hvadid=641638718575&hvpos=&hvnetw=g&hvrand=6235607503535841976&hvpone=&hvptwo=&hvqmt=&hvdev=t&hvdvcmdl=&hvlocint=&hvlocphy=9045915&hvtargid=pla-1640846664898&psc=1&mcid=e02a7d1495603634ba0636b3393dbad5&th=1&psc=1

Obviously a limited use here but very effective. Usually when you turn to get the pliers out something has failed, stuck or broken, these really do grip like hell to avoid slipping and seem a good addition to a toolkit.

Cheers

Brian