Author Topic: CB750 K7 carb rebuild. Where does this O rings go???  (Read 5001 times)

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Offline joedanger11

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CB750 K7 carb rebuild. Where does this O rings go???
« on: March 24, 2012, 05:12:37 PM »
I have a 1977 CB750K and tore down the carbs for cleaning and rebuild.  It was in OK condition and looked like someone tore it down before and left out some pieces.

I purchased the OEM Honda Carb Rebuild Kit and am having trouble locating where some of the O rings go.

I think I've figured out the location of all the seals except number 4.

Oring 1: Fuel Rail Tube
Oring 2: Float Bowl Drain Screw
Oring 3: Fuel Rail Tube
Oring 4: ?????
Oring 5: Pilot Jet


Can someone help me??  Also, I don't see a flat washer for any of my pilot jets, where can I find those?

Thanks!!




« Last Edit: March 24, 2012, 05:38:24 PM by joedanger11 »

Offline Drewster

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Re: CB750 K7 carb rebuild. Where does this O rings go???
« Reply #1 on: March 24, 2012, 05:56:39 PM »
Choke rail??

Offline 77honda

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Re: CB750 K7 carb rebuild. Where does this O rings go???
« Reply #2 on: March 24, 2012, 06:02:07 PM »
When I overhauled my K7 carbs, the small flat washer on the pilot screw was stuck inside the carb body. I used a piece of 1.5mm welding wire and made a small hook on one end to remove the "o"ring and washer. The PO had installed the washer first then the oring.

Not sure about oring no. 4
CB750 K7

Offline MasterChief750

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Re: CB750 K7 carb rebuild. Where does this O rings go???
« Reply #3 on: March 25, 2012, 09:05:55 AM »
one of the o rings goes on the accelerator pump on #2 where the fuel comes through the bowl to the carb body. you will be left with some o rings from some of the kits when its all said and done you should be left with 3 accelerator pump o rings and 2 fuel tube o rings

its next to the number one in the parts diagram it goes next to the screw hole.
« Last Edit: March 25, 2012, 09:16:22 AM by MasterChief750 »
1978 CB750 K - Project Red Headed Step Child
1976 CB750 K - Drag Bike
Some things i know, others i dont.
I AM THE STIG
Sam is THE STIG
he said i can be STIG3 tho

Offline joedanger11

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Re: CB750 K7 carb rebuild. Where does this O rings go???
« Reply #4 on: March 25, 2012, 01:10:55 PM »
Ok, I get it now!  Thanks!!

Anyone know where I can get that pilot jet washer?  2 of my carbs are missing it. 

Offline 77cb750speed

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Re: CB750 K7 carb rebuild. Where does this O rings go???
« Reply #5 on: June 12, 2012, 09:52:21 PM »
You can get the washers off eBay. Look for the whole setup o ring washer and spring and ask if you can just get the washer. I was lucky and found someone that just gave me 4 used washers for nothing. His user name is stealthracingtech on eBay and you can search 380321542606 that is the item # or search Fuel Mixture Screw *PARTS KIT spring, washer & o-ring. Its easier to search the item # as it takes you straight to the listing.

Offline lucky

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Re: CB750 K7 carb rebuild. Where does this O rings go???
« Reply #6 on: June 12, 2012, 10:38:44 PM »
I have a 1977 CB750K and tore down the carbs for cleaning and rebuild.  It was in OK condition and looked like someone tore it down before and left out some pieces.

I purchased the OEM Honda Carb Rebuild Kit and am having trouble locating where some of the O rings go.

I think I've figured out the location of all the seals except number 4.

Oring 1: Fuel Rail Tube
Oring 2: Float Bowl Drain Screw
Oring 3: Fuel Rail Tube
Oring 4: ?????
Oring 5: Pilot Jet


Can someone help me??  Also, I don't see a flat washer for any of my pilot jets, where can I find those?

Thanks!!



The 1977 also has a small O ring on the top edge of #2 float bowl for the accelerator pump circuit.

And one more thing... if it has the black rubber hoses between the accelerator circuits on each carb there are little restrictor brass tubes inside those hoses to raise the pressure to the nozzles. cut those out and put them in some clear plastic tubes so you can see them.
« Last Edit: June 12, 2012, 10:43:05 PM by lucky »

bollingball

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Re: CB750 K7 carb rebuild. Where does this O rings go???
« Reply #7 on: June 13, 2012, 12:14:19 AM »
http://www.siriusconinc.com/search_result.php?make=1&model=cb750&part=1&partno=&search=search&x=33&y=16&start=50

You can get the o-rings and washers here. Scroll down to the bottom of page 3 and middle of page4

Ken

Offline Jellybean_Cowboy

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Re: CB750 K7 carb rebuild. Where does this O rings go???
« Reply #8 on: June 27, 2017, 07:09:06 PM »
Sorry to resurrect an old topic, but I read the comment about the PO installing the washer first then the o-ring for the pilot screw.  I just tore mine down and they were the same way.  Is that not correct then?

Thanks!

Offline flybox1

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Re: CB750 K7 carb rebuild. Where does this O rings go???
« Reply #9 on: June 28, 2017, 07:02:03 AM »
on the Idle Mixture screw install the spring, washer, o-ring goes on last.
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Offline Jellybean_Cowboy

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Re: CB750 K7 carb rebuild. Where does this O rings go???
« Reply #10 on: June 28, 2017, 05:37:45 PM »
Thanks for the clarification!