Jump to content

1977 Honda CVCC, fuel delivery issue


Recommended Posts



i have a 1977 Honda CVCC, 1.5L, 4-speed manual transmission. It generally has run fine for a very long time, but suddenly a strange fuel supply issue has happened.


it has a rebuilt carb, new electric fuel pump, new oil pressure sensor. The issue, is that the fuel pump will start pumping fuel ultra fast, like I am full throttle up a hill, and not stop, and the engine floods. 


There is also fuel coming out of the primary needle valve when this is happening. 

the fuel cut-off solenoids on the carb are functioning. I have tried adjusting the needle valves, idle adjust… nothing seems to make any significant change to the strange fuel pump issue.


any ideas would be much appreciated!



Link to comment
Share on other sites

How close are you to Salt Lake City and the JDM Legends guys?😄


Seriously- hard to believe the CVCC is 45 years old. I know little to nothing about Japanese carburetors and unsure if Carbking on here does much with them.


My best advice is get a copy of the Honda's factory service manual and set up the carb by it. I'm not aware of any variable speed or output electric fuel pumps but sounds to me like the pump output pressure is overpowering the carb's needle and seat, or whatever Honda used to regulate fuel supply to it.


I will say if Hondas are like my modern Fords they don't like aftermarket fuel and electrical system parts. 

  • Like 4
Link to comment
Share on other sites

Is the pump aftermarket? It probably has too much fuel pressure. Carb solenoids have nothing to do with it. The fuel is controlled by the float valve. That means 1) There is trouble with the needle and seat or the float, or, 2) the fuel pressure is too high.


The pump should run like crazy until the carb is full, then slow down and stop when the float valve closes.


Is the carb float plastic, and if so was it replaced?


What is the spec for fuel pressure, and how much pressure do you have now?


Welcome to the forum!


  • Like 1
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Create New...