carb

[Partycattin]

Carb question for you gurus.
I have a 750 holley on my 7.4. Ever since I put the Imco Powerflows on, the boat struggles to start.
If I turn it over with no throttle, it will start after a lot of cranking. Almost like it is flooded a bit.
If I give it just a bit of throttle, it will start but seems like it is loaded up a bit.
Is there an adjustment I can mess with to correct this? The motor used to start very easy.

[Cheap Thrills]

Sounds like either the float level is set to high or the power valve is leaking down.
pull the sight plug off the side of the bowls and check the fuel level. if fuel pours out the sight plug the float is set too high. The fuel level should'nt be any higher than the bottom of the sight hole. If you pull the plug and there isn't any fuel either it's set too low or the power valve is leaking down.
The power valve is only on the front bowl on most Holleys. check the float level in the rear bowl also.
Just my nickle's worth
Good Luck
C.T. :wink:

[Partycattin]

Sounds like either the float level is set to high or the power valve is leaking down.
pull the sight plug off the side of the bowls and check the fuel level. if fuel pours out the sight plug the float is set too high. The fuel level should'nt be any higher than the bottom of the sight hole. If you pull the plug and there isn't any fuel either it's set too low or the power valve is leaking down.
The power valve is only on the front bowl on most Holleys. check the float level in the rear bowl also.
Just my nickle's worth
Good Luck
C.T. :wink:
I tried both those last summer. For awhile the boat wasn't running well at all. It kept loading up if running at slow speeds. The float level was fine but we swapped out the powervalve and it helped. Still didn't solve the start up situation though. All this seemed to start with the change in the exhaust.

[Cheap Thrills]

the only other thing I can think of thats easy to fix would be to replace the needle and seat on both bowls. if theyre worn they will cause a rich condition.
when you shut the engine off the remaining pressure in the fuel line could be leaking past the needle and seat. weak spark could cause a rich condition as well as low compression. Oh yeah if you have an adaptor plate on the carb and the carb has been off recently make sure the plate is right side up I have a composite spacer that caused me all sorts of headaches. if it is facing the wrong way the power valve wont get any vacume signal.
Also check for vacume leaks by squirting a little WD40 arround the carb and where the intake bolts to the heads while it's running. You may be mistaking a lean condition for rich.
I'm not convinced the IMCOs are causing your problems.
Best of luck.
C.T. :wink: