84 CB650SC Issues and trouble shooting

JHeppHawk

New Member
Joined
Jul 17, 2015
Messages
2
Location
Ontario canada
Hey,
So I recently picked up a basket cast 84 nighthawk. Had to repaint the whole thing, soaked and cleaned the carbs got new gaskets on it and new manifolds off the block to the carbs. Just trying to get this thing running stoke. I'm having a hard time figuring out the way the fuel lines are run. I know there's a vacuum line from the petcock to carb #2. But there's 3 nozzles in between each carb that need (what I'm assuming are fuel lines) something hooked up to them. Can someone please help me..I'm stuck and the Clymers manual isn't helping me. The only diagram in the book is for the California model.
 
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Hey,
So I recently picked up a basket cast 84 nighthawk. Hag to repaint the whole thing, soaked and cleaned the carbs got new gaskets on it be manifolds of the block to the carbs. Just trying to get this thing running stoke. I'm having a hard time figuring out the way the fuel lines are run. I know there's a vacuum line from the petcock to carb #2. But there's 3 nozzles in between each carb that need (what I'm assuming are fuel lines) something hooked up to them. Can someone please help me..I'm stuck and the Clymers manual isn't helping me. The only diagram in the book is for the California model.

I have the next Nighthawk in the series, the 700. It's derived from but not based on the 650, so there are many similarities.

First of all, Clymers' manuals are pretty much garbage. I use mine as jackstand padding because it's not any good as a manual. You can view a bootleg copy of the factory service manual here: https://app.box.com/motorcyclemanuals

Here's a reference with color photos someone put together: http://www.bobberforum.com/forums/showthread.php?tid=558

If you download the second one (81mb PDF) you'll find that he's got lots of pictures of what's supposed to go where.

The three tee fittings between the carbs? The ones between each outer pair are your air vent tubes. The tee fitting in the middle of the rack of carbs, mounted low down is where the fuel line from the petcock goes. I suggest putting an inline filter somewhere in the hose between the carbs and petcock.

Edit: Here is a picture of the very similar 700's rack of carbs. This one's from a CA market 700 so it has some extra vacuum-type lines, but you can see the two air vent tubes between the pairs of carbs and the fuel feed tee in the center with the S-shaped fuel line coming off of it.

$_57.JPG
 
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Okay great Thankyou!
I got it running, but apparently the petcock had a bad diaphragm which overt flowed the fuel into the block and down into my oil reservoir. New petcock cane today, already swapped out the bad oil. Fingers crossed everything's good now.
 
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