I ordered the kit to change my secondary vacuum spring on my holley 4160-type carb. I thought it was going to be easy until I took a closer look at the carb and realized one of the 4 screws holding down the top plate sits directly underneath the main lip of the carb openiing. How do you get this screw out?

AA,
I always take the entire secondary unit off the carb to do it. Let me give you a hint ... take the entire unit and before you take the top off, sit it in a vise with the rod clamped in the vise. make sure the "body" is down all the way sitting on the top of the vise jaws. This will keep the diaphram from moving around while you try to put the top back on. Also ... be very careful when you put the screws back in. They like to grab the diphram and twist it all to pieces. Put a little oil on them, it helps a lot.
Have fun,

while ur at it you might want to consider the quick change kit from holley.it is $11.99 through jegs. (Part # 510-20-59) u will be much happier the next time u need to change springs.

mike

Sounds like I have to pull the whole carb off the car. How do I get the secondary unit off. Do I start with the 4 nuts holding the secondary fuel bowl cover? I'm new to this in case you can't tell.

Remove the screws holding the vacuum pod and undo the C clip from the rod and out it comes. Then remove the philips screws on top and the spring is snapped on the diaphram. Swap the spring, and click it in and watch the diaphram when you reinstall it, you don't want to pinch the diaphram holes.

Definitely get the quick change cover and a set of springs. Makes tuning the car easy as taking two screws out next time.

Remove the screws holding the vacuum pod and undo the C clip from the rod and out it comes. Then remove the philips screws on top and the spring is snapped on the diaphram. Swap the spring, and click it in and watch the diaphram when you reinstall it, you don't want to pinch the diaphram holes.
And if you have an electric choke you may have to remove that before you can get to the screws holding the vacuum pod.