Carb cleaning questions

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Carb cleaning questions

seestheday
Hi,
I'm in the process of cleaning my carbs following the write-up from the repairs section and have a few questions.  I'm hoping someone here will be willing to help me out.

1. The write-up mentioned that I need to make sure I don't lose the o-ring from my accelerator pump.  Well, it was already missing when I opened them up.  Where can I get a new one?

2. How do I get the fuel mixture screw washer & o-ring out?  I see them in there and there is no way they'll shake out, and no way I can get something down there to fish them out.  I was thinking of making a tiny hook with a really thin piece of wire, but I'm not sure if that is the best idea.

3. Why do I need to remove the cap from the fuel mixture screw?  I believe I'll have to heat it to get it off, and I don't understand why I need to remove it at all.  At the bottom of this post is a pic of my fuel mixture screw.

4. Do I need to replace the bowl gaskets?  The write-up doesn't mention removing them so I have them soaking in pine-sol at the moment, I'm hoping that one of you doesn't tell me I need to remove them right away.  Below is a pic of the gasket that looked the worst.


1981 CB750K with 900 cams
90K KM's, rebuilt head, rebuilt carbs, upgraded valve stem seals

My wife's recipe website that I'm trying to help promote: Strawberries for supper. Yes, I am a lucky man.

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Re: Carb cleaning questions

TOOLS1
Administrator
You can get an O-ring at any auto parts store.

The hook on the end of a piece of wire is how I do it.

Removing the cap, or just the tab will make it easier to adjust it later.

The bowel gasket should be all right. I do not know what pine-sol will do to rubber though. I do know carb cleaner will soften, and deform them. I never soak the bowels. I just use spray carb cleaner on them.

TOOLS
Life is not about the number of breaths, you take, but the moments that take your breath away.
I don't have an anger problem. I have an idiot problem. Hank Hill
Never confuse education for intelligence.
Happiness is a belt fed weapon.
I just can't imagine what could go wrong.
No fire? No explosions? So whats the point of your story?
Those who are too smart to engage in politics are punished by being governed by those who are dumber. ~Plato
It couldn't be done, but the darn fool didn't know it, and did it anyway.
We all got problems. Ksharp
I like vintage bikes because they take me away from the clutter of technology that I work with everyday and back to a simpler time of mechanical elegance and simplicity.. "ninadm"
Darkwing Duck: The worst part of public transportation is the Public.
"That is awesome shit there" Re-Run
"Fear nothing, attack everything" Eric Berry
" Oh, you read that on the internet? Clearly it IS a massive problem. Of course it CAN’t be normal operation."

1976 CB 750-A X 2
1977 CB 750-A X 4
1977 CB 750-K
1976 CB 750 F
1981 CB 750
1966 Kawasaki SG 250
1981 KZ 750 LTD
1973 CB 350
1979 CM 185 Twinstar
1982 Honda XL 80
South of Eden (Kansas City MO)
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Re: Carb cleaning questions

seestheday
Thanks Tools, really appreciate the help.
1981 CB750K with 900 cams
90K KM's, rebuilt head, rebuilt carbs, upgraded valve stem seals

My wife's recipe website that I'm trying to help promote: Strawberries for supper. Yes, I am a lucky man.

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Re: Carb cleaning questions

cityslicker
information absorbed, retained for later, (hopefully)
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Re: Carb cleaning questions

seestheday
Good to hear it's benefiting someone.  I'm taking lots of pics and plan to update the how-to with everything I'm learning.  Gotta try to contribute to this forum somehow instead of always taking :-)
1981 CB750K with 900 cams
90K KM's, rebuilt head, rebuilt carbs, upgraded valve stem seals

My wife's recipe website that I'm trying to help promote: Strawberries for supper. Yes, I am a lucky man.

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Re: Carb cleaning questions

seestheday
In reply to this post by TOOLS1
Tools, one more question.

I don't see a tab, and why do I need to adjust it?  The instructions don't mention adjusting it anywhere.
1981 CB750K with 900 cams
90K KM's, rebuilt head, rebuilt carbs, upgraded valve stem seals

My wife's recipe website that I'm trying to help promote: Strawberries for supper. Yes, I am a lucky man.

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Re: Carb cleaning questions

TOOLS1
Administrator
Someone might have removed it all ready. When, you put it back together, screw it in until it bottoms out. Then back it out 1 1/2 turns. After starting the bike, and warming it up, adjust each one until, you get the highest idle. If the idle is too fast, adjust it down with main idle adjuster. After that sync the carbs with a set of gauges. The bench method will only get them close, not exact.
TOOLS
Life is not about the number of breaths, you take, but the moments that take your breath away.
I don't have an anger problem. I have an idiot problem. Hank Hill
Never confuse education for intelligence.
Happiness is a belt fed weapon.
I just can't imagine what could go wrong.
No fire? No explosions? So whats the point of your story?
Those who are too smart to engage in politics are punished by being governed by those who are dumber. ~Plato
It couldn't be done, but the darn fool didn't know it, and did it anyway.
We all got problems. Ksharp
I like vintage bikes because they take me away from the clutter of technology that I work with everyday and back to a simpler time of mechanical elegance and simplicity.. "ninadm"
Darkwing Duck: The worst part of public transportation is the Public.
"That is awesome shit there" Re-Run
"Fear nothing, attack everything" Eric Berry
" Oh, you read that on the internet? Clearly it IS a massive problem. Of course it CAN’t be normal operation."

1976 CB 750-A X 2
1977 CB 750-A X 4
1977 CB 750-K
1976 CB 750 F
1981 CB 750
1966 Kawasaki SG 250
1981 KZ 750 LTD
1973 CB 350
1979 CM 185 Twinstar
1982 Honda XL 80
South of Eden (Kansas City MO)
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Re: Carb cleaning questions

mikefootusa
In reply to this post by seestheday
Hey sees....love your nick by the way....lol.

The Oring you are looking for is a "dash" 901 buna-N  O'ring.  Here's a link to a site that give you sizes for cross reference.           http://www.orings.com/pdf/SIZES2_pdf.pdf

Here is a link to a great carb rebuild guide:
http://www.google.com/url?sa=t&source=web&cd=1&ved=0CBoQFjAA&url=http%3A%2F%2Fwww.cb750c.com%2Fpublicdocs%2FSeanG%2FHonda_Carb_Manual_revE.pdf&rct=j&q=macgregor%20carb%20cleaning%20honda_carb_manual_revE.pdf&ei=9q2JToOwNIPegQe5wZz6Cg&usg=AFQjCNEmSmzw9aIam2qmA7UAwPZ309Y5Jg&sig2=A2e2jvA9r9A4UvfIISOENQ&cad=rja

In 1972 I had to make a choice...quit riding...or quit drinking.  God says it's safe to get back in the saddle now...at least I'm still alive...and feel more alive with the wind in my face!  Now riding "Helen Black"...1982  CB750SC.
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Re: Carb cleaning questions

seestheday
Mike, that's great - Thanks for both of those links.

The rebuild is very detailed and goes further than I am going to go.  I'm really just doing a cleaning as opposed to a rebuild unless I really have to.  However it is still very useful.  Lots of very detailed cleaning tips that I hadn't thought about.

My carb bank is almost ready to come out of the pine-sol soak so this is very timely.

Regarding my nick, I used to be in a punk band back when I was in my early twenties called "Sees The Day" and I used the online handle.  It just ended up sticking around.
1981 CB750K with 900 cams
90K KM's, rebuilt head, rebuilt carbs, upgraded valve stem seals

My wife's recipe website that I'm trying to help promote: Strawberries for supper. Yes, I am a lucky man.

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Re: Carb cleaning questions

TOOLS1
Administrator
Just wait. Someone here will photoshop a purple Mohawk, and a piercing on your photo.
TOOLS
Life is not about the number of breaths, you take, but the moments that take your breath away.
I don't have an anger problem. I have an idiot problem. Hank Hill
Never confuse education for intelligence.
Happiness is a belt fed weapon.
I just can't imagine what could go wrong.
No fire? No explosions? So whats the point of your story?
Those who are too smart to engage in politics are punished by being governed by those who are dumber. ~Plato
It couldn't be done, but the darn fool didn't know it, and did it anyway.
We all got problems. Ksharp
I like vintage bikes because they take me away from the clutter of technology that I work with everyday and back to a simpler time of mechanical elegance and simplicity.. "ninadm"
Darkwing Duck: The worst part of public transportation is the Public.
"That is awesome shit there" Re-Run
"Fear nothing, attack everything" Eric Berry
" Oh, you read that on the internet? Clearly it IS a massive problem. Of course it CAN’t be normal operation."

1976 CB 750-A X 2
1977 CB 750-A X 4
1977 CB 750-K
1976 CB 750 F
1981 CB 750
1966 Kawasaki SG 250
1981 KZ 750 LTD
1973 CB 350
1979 CM 185 Twinstar
1982 Honda XL 80
South of Eden (Kansas City MO)
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Re: Carb cleaning questions

seestheday
In reply to this post by mikefootusa
Shoot, I am reading that rebuild guide from Mike and it appears that I'll need new float valves.
My current ones definitely have a slight groove worn into them and the guide says that will cause problems.

The float valves are still conical and pliable, its just that they have a visible line on them where it looks like it's almost worn smooth a bit.  Not sure if it's actually a groove though.  I'll check to see if I can feel a dip or snag on it with my fingernail tonight.
1981 CB750K with 900 cams
90K KM's, rebuilt head, rebuilt carbs, upgraded valve stem seals

My wife's recipe website that I'm trying to help promote: Strawberries for supper. Yes, I am a lucky man.

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Re: Carb cleaning questions

TOOLS1
Administrator
If they were not leaking before they should be all right. Does yours have the rubber tip, or solid metal?
TOOLS
Life is not about the number of breaths, you take, but the moments that take your breath away.
I don't have an anger problem. I have an idiot problem. Hank Hill
Never confuse education for intelligence.
Happiness is a belt fed weapon.
I just can't imagine what could go wrong.
No fire? No explosions? So whats the point of your story?
Those who are too smart to engage in politics are punished by being governed by those who are dumber. ~Plato
It couldn't be done, but the darn fool didn't know it, and did it anyway.
We all got problems. Ksharp
I like vintage bikes because they take me away from the clutter of technology that I work with everyday and back to a simpler time of mechanical elegance and simplicity.. "ninadm"
Darkwing Duck: The worst part of public transportation is the Public.
"That is awesome shit there" Re-Run
"Fear nothing, attack everything" Eric Berry
" Oh, you read that on the internet? Clearly it IS a massive problem. Of course it CAN’t be normal operation."

1976 CB 750-A X 2
1977 CB 750-A X 4
1977 CB 750-K
1976 CB 750 F
1981 CB 750
1966 Kawasaki SG 250
1981 KZ 750 LTD
1973 CB 350
1979 CM 185 Twinstar
1982 Honda XL 80
South of Eden (Kansas City MO)
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Re: Carb cleaning questions

seestheday
Rubber tip.
Sent from my BlackBerry device on the Rogers Wireless Network

From: "TOOLS1 [via Honda CB750'S]" <[hidden email]>
Date: Tue, 8 Nov 2011 13:49:02 -0800 (PST)
To: seestheday<[hidden email]>
Subject: Re: Carb cleaning questions

If they were not leaking before they should be all right. Does yours have the rubber tip, or solid metal?
TOOLS
Life is not about the number of breaths, you take, but the moments that take your breath away.
I don't have an anger problem. I have an idiot problem. Hank Hill
Never confuse education for intelligence.
Happiness is a belt fed weapon.
I just can't imagine what could go wrong.
No fire? No explosions? So whats the point of your story?
Those who are too smart to engage in politics are punished by being governed by those who are dumber. ~Plato
1976 CB 750-A X 2
1977 CB 750 A
1981 CB 750
1995 KZ 1000 P-14
1981 KZ 750
1979 CM 185 Twinstar
1987 Honda TLR 200
1982 Honda XL 80
2005 Yamaha PW 50
South of Edan (Kansas City MO)



If you reply to this email, your message will be added to the discussion below:
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1981 CB750K with 900 cams
90K KM's, rebuilt head, rebuilt carbs, upgraded valve stem seals

My wife's recipe website that I'm trying to help promote: Strawberries for supper. Yes, I am a lucky man.

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Re: Carb cleaning questions

Lucky 1
This post was updated on .
In reply to this post by seestheday
You do not need to replace float bowl gaskets unless they were leaking.
When I worked at a dealership it was VERY rare that one got replaced.
Make sure that before you put the float bowl back in place to put a light coating of petroleum jelly on the o ring so it does not stick.

As far as that "O" ring missing on that #2 carb with the accelerator pump
we will need a good photo of the float bowl mating surface and the accelerator pump rubber part.
Maybe it needs the O ring and maybe it is part of that accelerator pump diaphram rubber.

BTW..That fuel mixture screw should have an O ring AND a flat washer. Look inside the hole and dig it out carefully with a paper clip or dental tool.

One more thing....You should have named this thread the same as the first part so we can all have the history. "DOHC cleaning procedure part II"
I looked at the parts photo on the other thread ( DOHC cleaning Procedure)and it looks like you might not need the o ring because the area around the check ball on the top edge of the float bowl is beveled instead of a lip for an o ring to sit in.
On a Roadstar Adventure.
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Re: Carb cleaning questions

Daddyman
Chapstick works great on gaskets too, and easier to apply.
Photobucket
---1976 CB750F CAFE---
     Florence, Colorado
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Re: Carb cleaning questions

Lucky 1
Sounds good. Good idea.
On a Roadstar Adventure.
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Re: Carb cleaning questions

TOOLS1
Administrator
In reply to this post by seestheday
With the rubber tips it is a 50/50 shot that they will still seal, but try them. The metal ones never go bad.
TOOLS
Life is not about the number of breaths, you take, but the moments that take your breath away.
I don't have an anger problem. I have an idiot problem. Hank Hill
Never confuse education for intelligence.
Happiness is a belt fed weapon.
I just can't imagine what could go wrong.
No fire? No explosions? So whats the point of your story?
Those who are too smart to engage in politics are punished by being governed by those who are dumber. ~Plato
It couldn't be done, but the darn fool didn't know it, and did it anyway.
We all got problems. Ksharp
I like vintage bikes because they take me away from the clutter of technology that I work with everyday and back to a simpler time of mechanical elegance and simplicity.. "ninadm"
Darkwing Duck: The worst part of public transportation is the Public.
"That is awesome shit there" Re-Run
"Fear nothing, attack everything" Eric Berry
" Oh, you read that on the internet? Clearly it IS a massive problem. Of course it CAN’t be normal operation."

1976 CB 750-A X 2
1977 CB 750-A X 4
1977 CB 750-K
1976 CB 750 F
1981 CB 750
1966 Kawasaki SG 250
1981 KZ 750 LTD
1973 CB 350
1979 CM 185 Twinstar
1982 Honda XL 80
South of Eden (Kansas City MO)
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Re: Carb cleaning questions

Peterwh
Are these carbs off of a SOHC or a double?  Are they the same?
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Re: Carb cleaning questions

Lucky 1
In reply to this post by TOOLS1
That is not true.
The solid metal float valve needles had a different problem.
The vibrations of the engine would create a ridge on the needle.
When you look at the needle you can see a shiny ring around the tip
where it mates with the seat.
If you use a magnifying glass you will see that the shiny part is indented
and there can be a ridge. That caused them to leak.

That is why all of the float needle now have a rubber tip.
With the solid metal ones if the needle was bad you have to buy a new seat as well but with the rubber tipped needle you just replace the needle and not the brass seat.

It saved a lot of brass in the world being thrown away.
Many people make the mistake of throwing precious metals in the garbage instead of
recycling it. Save all of your brass  and at the end of a year you will enough to buy a
nice meal and some gas. IF you have a brass radiator then you really get back some dough.
On a Roadstar Adventure.
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Re: Carb cleaning questions

Lucky 1
In reply to this post by Peterwh
Basically yes.
On a Roadstar Adventure.
12