600 holley

[reborn55]

Friend gave me a 600 Holley(1850) to replace  my 4010.  Just took off his running car.  put it on wife's coupe---starts and runs great.  After it sets over night it will leak fuel out of the rear of it somewhere.  Has standing gas on in the valley of the intake.  Checked floats--they are OK, cleaned needle and seat, tightened everything up.  Don't want to invest in a kit if there may be other problems.  Had a similar problem on a Holley in the past and it is still on the shelf cause I could not fix it.  Also the idle mixture screws don't appear to be doing there job.  Screw them all the way in and it just barely has any affect.  thanks

[chimp koose]

If your primary throttle blades are open too far the idle mixture  screws will have little or no effect . Verify that your ignition timing is correct.Late spark timing will cause the need to open the throttle wider to maintain idle speed which in turn effects idle mixture adjustment.If your ignition timing checks out correct then you would want to open up your secondary throttle blades slightly.  This would allow you to close down the primaries enough to gain back idle mixture adjustment.When primary throttle blades are open too far they expose the 'off idle circuit' (the small vertical slot in the throttle bore just above the idle screw) allowing extra fuel in and reducing idle mixture adjustability.

[wayne petty]

one more thing..  if the power valve is blown..  turning the idle mix screws in will have almost no effect..

as the motor is getting fuel through the power valve directly into the intake manifold..

do you have an electric fuel pump sitting in your box of stuff...

hang the carb right side up from the air cleaner stud..    hook up the fuel pump.. fill the carb... let it sit.. hanging in the air.. see where its leaking at..

you can also just fill the vents with a squeeze bottle..  after the extra fuel drips out.. watch where else it comes from...

[reborn55]

OK--found out the carb is obsolete by the number.  Holley has a kit number 3-1024--do you recommend using that kit--$42.00 and up or a holley generic kit for about $20.00. by looking at the pictures, can't see a lot of difference.  Thanks

[wayne petty]

go generic...

check the part numbers on the ends of the inside box.. they are probably the same..

put together by walker products..    not walker exhaust..

http://www.walkerproducts.com/_pdf/holley4barrel.pdf

[reborn55]

Great info---only problem with the generic Holley kit is that there is no Vacuum Secondary diaphram, and not sure on the correct power valve.

Thanks for all the help

[wayne petty]

most will have a 6.5 power valve...

some come with several...

do you need the secondary  parts?

[reborn55]

Don't think so, but better to be safe than sorry

[enjenjo]

Check the carb base plate. Some that were originally intended for GM applications have a vacuum passage that is not sealed with standard holley gaskets.

[tomslik]

i'd use a holley kit UNLESS the cheapo kit has holley-type needle+seats.
why?
seen too many float bowls stripped out...

[reborn55]

Drove the car about 10 miles yesterday and this morning there was no fuel leak at all---in the area where puddles were before were bone dry.  Only difference was that I left the gas cap off all night.  It has late model type plastic screw in cap.  It is vented the best I can tell,b ut I have not been able to see if the tank is vented.  Looks like it might be the original tank or an early version of a tank.  Has one metal line coming out of the tight front for fuel, but can't see anyother hoses anywhere.  Can't see on top to tell either.  But then there was no leak with the 4010 carb.  Thanks

[GPster]

Just a strange thought that I can't remember where I picked it up. Because this carb it now sitting on a different manifold than it was maybe the difference creates this problem. If your manifold is on a different slant than it was on a different engine in a different chassis maybe the float level is a little off. Also if it's on a cast iron manifold with exhaust carb heat passage maybe you need a little insulation from a carb base gasket. GPster

[chimp koose]

x2 tomslik.Check threads on needle and seat on no name stuff!