Primer keeps running when trying to start

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Fire-medic

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Because of the tiny orifices for the pilot jets, they readily become plugged, often due to rust from the gas tank, or contaminated fuel. A decent fuel filter like the Russell sintered-bronze rebuildable ones (there are generics) helps. I've never put any faith in 'tune-up in a can' products. Removal of the carburetors isn't hard at-all, just loosen the upper clamps on the VBoost manifold rubber 'donuts,' and use a long pry bar to pop-up one side of the carburetors at a time. Be careful on where you pry. Potmetal carburetor bodies will crack if you're careless about removal. With the cost of the bodies, and the unavailability of some of the bodies new, take your time for removal.

I disconnect the throttle cables at the junction box on the left side under the air scoop. Be careful not to lose the tiny screws holding the junction box together, and snap a phone pic of the way the cables are connected, to guide you in reassembly.

Replacing the carburetors, ensure that the lower ports going to the VBoost are fully-inserted into the rubber donuts, and that the airbox is also fully-mated to the airhorns (the topmost air passage on the carbs. (52) Pods? New air box? | Page 2 | Yamaha Star V-Max VMAX Motorcycle Discussion Forum (vmaxforum.net) See post #32. Check that you've adequately-tightened the clamps. It's almost impossible to over-tighten the OEM clamps. They have a small stop which when your compression band touches that, they're OK.

Splitting the carburetor rack into two halves is almost always as-far as you need to go, to access the pilot jets, which require removal of the float bowls and the jet blocks. Have four new jet block gaskets on-hand, as they often tear during the removal process. This is one place where I use aftermarket carburetor parts, the K&L brand is an OEM supplier to Japanese manufacturers. Brass parts, if needed, go OEM, and stay-away from the ebay generic, no-name 'lookit all these parts!' carb kits.

Removal of the pilot jet and the other jet requires a tight-fitting screwdriver the width of the holes in the jet block into-which the brass jets reside. Note those holes are two different sizes. Placing the proper width screwdriver with a snug-fitting blade into the jet slots, and then a couple of moderate raps on the end of the handle will help in removal of the brass jets. I'd try it dry first and only use penetrating oil (PB Blaster, ATF/acetone mix, or similar) if you cannot easily remove the jets.
 
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DreamV4

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Yes but... I would always try running some carb cleaner in the fuel first before attempting anything else. I've used Forte products (available in the US?) with some success.

Splitting the carburetor rack into two halves is almost always as-far as you need to go, to access the pilot jets, which require removal of the float bowls and the
[/QUOTE]
I had to take them allapart from each other
In looking at the "shotgun" cleaning instructions, I was thinking that the idle mixture screw needed to come out in order to clean the jets. is that not correct?
No. Removing idle screw doesn't give you access to jets. I marked whatever is often missed by beginners.
Article:
carb diagr.jpg
 

Fire-medic

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Work smart not hard, there is no need to break down the carburetors into 4 bodies. Break them into the two pairs you don't have to mess with the springs in the synch mechanism or the rods for the starter enricheners.
 
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