Honda CB360 Carburetor problems

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d_jgreene
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Honda CB360 Carburetor problems

#1 Unread post by d_jgreene »

Hello,
I recently purchased a CB360 and after riding it for a day found the right exhaust pipe was turning blue. I tried cleaning and synchronizing the carbs, and cannot get them to synchronize. The right carburator appears to have the correct vacuum about 18hg/cm, but the left carburator reads about 50hg/cm. Also, I thought the right cylinder must be running lean because of the blue tailpipe, but when I inspected the spark plug, it was covered in carbon. I think that it may instead be running rich. After trying to run the bike on each individual cylinder, I'm finding that the right cylinder was keeping the bike idling, and the left wasn't providing much power. To keep the bike running on the left cylinder only, I had to crank the idle way up. This of course caused the bike to idle very fast when the right cylinder was tried.

I'm new to working on bikes, does anybody have an idea of what the problem might be?

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MrShake
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#2 Unread post by MrShake »

Pull those carbs apart and clean them completely.
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d_jgreene
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Thanks for the reply

#3 Unread post by d_jgreene »

I did take the carbs off and disassembled/cleaned everything but the diaphragms on top. I noticed that there is a little spring driven nub on the bottom of the float valve that is frozen on one of the carburetors. I couldn't get it to move, but the float valve itself seems to move in and out. Also, the float bowl does fill with gas. Do you thing that could still be it?

Thanks

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#4 Unread post by MrShake »

possibly. Did you do a float bowl level check?
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d_jgreene
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#5 Unread post by d_jgreene »

No, I didn't do a float level check. I'm not sure exactly how to do that.

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honda750
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you should

#6 Unread post by honda750 »

find the specs for float height for a CB360

Remove the float chamber cover (bowl of the carbueretor), position the float to the point where the float arm barely touches the float arm. In this position, set the float level gauge vertically on the float. If an adjustment is necessary, make the adjustment by using a small screwdriver to bend the little tab that touched the float needle.

instead of a flat level gauge i usually use a metric ruler of some sorty, that's usually good enough.

thats how to measure/adjust float level
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d_jgreene
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Thanks

#7 Unread post by d_jgreene »

I'm going to try this today, and if it doesn't work purchase a couple of carb rebuild kits. When I previously disassembled the carbs to clean them I found a couple of the jets appear to be pressed fit into the carb. How can I remove these? Can I fish something into the intake opening of the carb and press them out, or do I need to disassemble the top of the carb remove the spring/diaphragm and press them out from the top?

Thanks

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id

#8 Unread post by honda750 »

id be really suprised if you have jets press-fitted into position.
your jets are all brass, and if they have a slot on the top they have to screw out.

go to this site: http://www.bikebandit.com/honda-motorcy ... /oem-parts

and select your year, then CB360T and it'll give u all the parts diagrams for your bike. Click on the CARB diagram, and it'll show u all your jets/ etc. you should be able to see if you have access from the top if you do have press-fitted jets.

i still would put money that they screw out.
when you do open it make sure you SOAK everything in carb/choke cleaner except for the rubbers, it can damage them.
good luck.
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d_jgreene
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Still struggling

#9 Unread post by d_jgreene »

Thank you everyone who has replied so far.

I have rebuilt both carburators, and it appears I still have a problem with the left carburator. I used a vacuum guage on both carbs and one reads about 20hg/cm and the other reads 30hg/cm. The manual lists that the carbs should be within 16-24hg/cm.

The manual says to check the intake gaskets, valves, carb diaphragms and timing if the carburators cannot be brought into the 16-24hg/cm vacuum range.

I have checked the intake gaskets, and the diaphragms and both look fine.

I'm wondering if I could have the valves out of adjustment or the timing is wrong.

Am I correct in thinking that if I had a timing problem or the points were bad that both carbs would show their vacuum readings out of range?

Oh, and I have also tried replacing the spark plugs.

Does anybody know of any other things I should check?

Thanks

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