Is there a way to richen the mixture without just getting a new jet? Im sure its running lean because it runs/pulls best with a little bit of choke (manual choke). Ive checked for leaks.
Which carb are you asking about - stock YF series? If it is, they do not have a jet you change size on. They use a metering rod that can be adjusted by a screw inside the YFA and by bending a tab in the early YF. Later YF's have the screw adjustment like the YFA. Of course there is the mixture screw, but that is for idle and just off idle. At speed the fuel goes through that metering rod. If it is a different carb you are asking about, please post which one.
I have the metering rod set to factory specs right now, how much is it going to have to come up? It has the screw. It almost seems like someone put yfa guts in a yf.
The screw can be found in the Maverick YF just like YFA's - earlier YF's in Bronco - Falcon and other Fords have the tab. I edited my post above so it is clearer on the screw adjustment. I've always just set it at factory. I don't know much about any mods for the metering rod.
I think just the opposite - but I'm no expert on how to power tune these things. The idea is to get the pump compressed down and have the metering rod bottomed out plus 1 turn. This will get the factory setting. Here is a list I found online. Most YFA carburetors would have the star type of adjusting screw. This adjustment is important and should be performed anytime the carburetor is rebuilt, or the metering rod replaced. Remove the carburetor. We do not recommend working on your carburetor while on the car. This would chance dropping something into the engine. Back out the idle screw until the throttle plate is completely closed. Bottom the diaphragm by pressing down on the diaphragm shaft. The metering rod should contact the bottom of the well. For models with an adjusting screw, turn the screw until the metering rod bottoms in the well. Turn the screw one more turn. For models without an adjusting screw bend the lever the metering rod is attached to until the rod bottoms out.
Ive done all the previously mentioned steps. Its funny, my adjustment screw is a phillips head screw. Ive had this thing open 3 times trying to richen the mixture, i cant get it dialed in.
With the metering rod adjusted to factory setting, i have to give it about half choke to tune it in to the right mixture. I just drive and have it at about 1/4 throttle and can slowly pull the choke till i feel it hit the "sweet spot". But any adjusting the metering rod yields either no improvement or makes it worse/leaner.
Yea, something is definitely wrong besides just adjustment. There isn't much to these carbs to go wrong. Plugged passage or vacuum leak. When was the last time it was rebuilt and was it boiled out?
It hasnt been long maybe 6 months. Yes i boiled it out and blew compressed air through everything. I didnt want to have to do it again.
The vacuum advance has 2 ports. Im assuming one is for ported and the other for manifold? but then whats the pvs for if thats the case. I need a diagram but the one place i found it before no longer has it.
On dual diaphragm distributors, the inner connection is for retarding the spark and that is manifold vacuum. Sometimes it goes to a thermal switch (the PVS) that blocks the vacuum until the coolant temp comes up. This is the line many leave off or plugged at the manifold connection. Don't plug at the distributor connection as that can hinder movement of the diaphragm, too little air in that side of the system. The outer connection is carburetor vacuum and must be connected. Here is the picture I think you were looking for: http://mmb.maverick.to/threads/vaccum-line-mix-ups.103945/#post-1056580
