Brand new carb bowl not filling, fuel delivery fine (1 Viewer)

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Hello, I recently replaced a dead fuel pump in my 60 after a fuel delivery issue, along with blowing out the lines. I also thought it would be a good time to buy a new City Racer aftermarket carb in order to rebuild my OEM.

I replaced the pump and fuel comes out of my metal line right at the carb at a good rate, but the carb bowl is not filling up at all. The FCS is a brand new 1 wire that came with the carb, and is known to be functioning. If I try blowing into the fuel inlet on my carb, I am unable to. However, I am able to blow into it with only medium resistance on my old carb. When I take off the fitting the metal line attaches to, I see what looks like a small brass mesh inside of the inlet on the carb, while the old carb does not have this. The PO doesn't have the best track record for doing repairs (including a desmog) properly so I do not have a good frame of reference on this.


I am stumped and would appreciate any guidance on what this could be. An assembly issue?
 
Adjust the float level. The brass strainer is supposed to be there. Make sure the new needle valve isn't stuck. It's just a small plugger with a rubber tip. Unscrew the brass strainer and inspect the needle valve.
 
Have someone crank it over while you tap on carb close to fuel inlet area
No luck.
Adjust the float level. The brass strainer is supposed to be there. Make sure the new needle valve isn't stuck. It's just a small plugger with a rubber tip. Unscrew the brass strainer and inspect the needle valve.
I inspect the valve through the fuel inlet? Does the brass strainer just pop out?
 
The 2F manual shows an exploded view of the original carburetor. Yours will be similar

image.jpeg
 
There were some issues with the City Racer carb a while ago where overzealous use of some sealing goop at the factory, for the needle/seat, caused a blockage in the inlet circuit. What I would do is find some tubing that will fit over the fuel inlet threads and see if you can blow past the blockage - if not (probably not), you'll have to remove the airhorn and remove the needle/seat and clear the passage.

There was a thread on it, somewhere.
 
Funny, I was just about to install a City Racer carb too and I had the same problem. The needle was in fact stuck. I opened up the carb to find and fix - but you could (as suggested) use some compressed air to blow through the fuel inlet.
 
Funny, I was just about to install a City Racer carb too and I had the same problem. The needle was in fact stuck. I opened up the carb to find and fix - but you could (as suggested) use some compressed air to blow through the fuel inlet.
No excessive goop found on disassembly.
 
I just installed a city racer Japanese carb ($295) and it wouldn't let gas into the float bowl. At the advice of Josh at Willamette Blvd. Service Center I took the carb apart and the float needle was too tight so I scraped a little material off each of the three raised sides and it works now. I am disappointed in the mid range performance vs the old weber that was leaking at the accelerator pump. Not sure if more tuning is needed but the midrange seems dead, I need to put the pedal to the metal to get power to the wheels verses the old EMPI carb (I guess that is a Chinese knock off of the weber 38/38). I took my wife and granddaughter to do the Bishops Pass road near Mt Hood and it ran pretty good at slow speeds but the trip there and back was disappointing.
 
I think both carbs deliver the same amount of fuel (the engine can only suck in so much) but the City Racer Fuji carb likely has a different fuel delivery curve vs throttle angle than the Weber.
If one carb quickly opens up near 1/2 to 3/4 throttle (Weber), the engine will feel "peppier" at mid throttle angles.
If the other carb gradually opens up linearly to WOT only when the gas pedal is floored, it'll feel more sluggish at mid throttle cruising.

The way to see if the Fuju carb is holding you back or not is floor it up a mountain grade or floor it during WOT acceleration and compare that performance to WOT flooring the Weber carb in the exact same way.

You'll likely find that at WOT, they're identical, but the Weber is twitchier near mid throttle - giving the impression of more power.

The feeling of power may only be your expectation of what the engine should feel like at 1/2-3/4 throttle based on the Weber's curve you've become accustomed to.
There's nothing wrong with pushing the gas pedal farther down to get the power you need. The Fuji won't suck more gas than the Weber.
 
I just installed a city racer Japanese carb ($295) and it wouldn't let gas into the float bowl. At the advice of Josh at Willamette Blvd. Service Center I took the carb apart and the float needle was too tight so I scraped a little material off each of the three raised sides and it works now. I am disappointed in the mid range performance vs the old weber that was leaking at the accelerator pump. Not sure if more tuning is needed but the midrange seems dead, I need to put the pedal to the metal to get power to the wheels verses the old EMPI carb (I guess that is a Chinese knock off of the weber 38/38). I took my wife and granddaughter to do the Bishops Pass road near Mt Hood and it ran pretty good at slow speeds but the trip there and back was disappointing.
Check to make sure the secondary diaphragm is working. Search paperclip test.
 

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