Cherrypicker
Member
I am working on well actually it is a Venture Xl early 90's vintage. These have the same engine and setup of the 480 Phazers.
I have pulled the carbs on many of these machines and they are in general difficult. I am wondering if there is anything that some of you do that might make this easier. I pop the little door on the fuel tank cover to expose the one or two bolts anchoring the air box, this gives minimal movement of the airbox. I pull the boost bottle, then remove the carb choke assembly with the choke lever activated to insure that the plunger/spring assembly doesn't come apart and fall in the engine bay. All hose clamps are loosened to the fullest extent, and the carbs are pulled back to come out of the intake manifolds, I work the carb rack CCW from the front so that the throttle cable and oil pump cable are more easily removed. Most of the gas lines in these older sleds are stiff and hard, so I used a "heat gun" hair blower to heat up the lines and soften then for removal from the carb spigots. I then wrestle the carb rack and boots until I can pull the assembly out. Frequently you might drop one of the air box clamps down in the engine bay, or distort them.
More recently in replacing the carb rack, I have moved the air box clamps all the way back over the carb throat and rolled the boot back so it is folder over the throat, this seems to give me a bit more clearance and install is by reversing the steps in removal. I have heated up the boots to make them a bit more pliable. Rolling the boots back onto the airbox so they properly fit is another time consuming process. While in there I'd recommend pulling the air box out to access the fuel pump and replacing the gas lines from pump to carb, maybe adding an inch or two in length, making it easier to reconnect the lines to the carbs.
I have pulled the carbs on many of these machines and they are in general difficult. I am wondering if there is anything that some of you do that might make this easier. I pop the little door on the fuel tank cover to expose the one or two bolts anchoring the air box, this gives minimal movement of the airbox. I pull the boost bottle, then remove the carb choke assembly with the choke lever activated to insure that the plunger/spring assembly doesn't come apart and fall in the engine bay. All hose clamps are loosened to the fullest extent, and the carbs are pulled back to come out of the intake manifolds, I work the carb rack CCW from the front so that the throttle cable and oil pump cable are more easily removed. Most of the gas lines in these older sleds are stiff and hard, so I used a "heat gun" hair blower to heat up the lines and soften then for removal from the carb spigots. I then wrestle the carb rack and boots until I can pull the assembly out. Frequently you might drop one of the air box clamps down in the engine bay, or distort them.
More recently in replacing the carb rack, I have moved the air box clamps all the way back over the carb throat and rolled the boot back so it is folder over the throat, this seems to give me a bit more clearance and install is by reversing the steps in removal. I have heated up the boots to make them a bit more pliable. Rolling the boots back onto the airbox so they properly fit is another time consuming process. While in there I'd recommend pulling the air box out to access the fuel pump and replacing the gas lines from pump to carb, maybe adding an inch or two in length, making it easier to reconnect the lines to the carbs.
I completely remove the clamps that tighten around the airbox side of the carburetor. I remove the plastic shrouding piece in front of where ones knee would be. Remove the intake piece over by the steering post for the airbox.
Remove airbox. Then remove anything else that attaches to carbs.
When re-installing, one of the last things I put on is the clamps around the airbox side of the carbs. Just feed them around and put the screws back in.
Remove airbox. Then remove anything else that attaches to carbs.
When re-installing, one of the last things I put on is the clamps around the airbox side of the carbs. Just feed them around and put the screws back in.
Cherrypicker
Member
I'm assuming you are talking about the shrouding on the left side for assistance in air box removal? Do you remove the driven sheave as well?
Regardless it is the most difficult of any Yamaha snowmobile I have worked on. Yeah I have taken the clamps off completely, the airbox ones and then fed them around, but you have to be very careful not to drop those screws when reinstalling them. I have several magnets on sticks, some with lights and flexible wands.
Regardless it is the most difficult of any Yamaha snowmobile I have worked on. Yeah I have taken the clamps off completely, the airbox ones and then fed them around, but you have to be very careful not to drop those screws when reinstalling them. I have several magnets on sticks, some with lights and flexible wands.
NorthofSixty
Member
I have several Phazers and Venture 480's that need re-jetting a couple times each year so I get a lot of practice pulling the carbs. In addition to what you are already doing I always disconnect the throttle and oil injection cables after removing the chokes but before trying to remove the carbs. I use 7/32" fuel lines that are much easier to remove and install especially as they age and harden. I put a small zip tie on each fuel line about 3" from the end to keep the spring clips from sliding down to the fuel pump. I replace the spring clips or use a pair of needle nose pliers to tighten them up a bit before reinstalling. I use a golf tees to plug the fuel lines. Like you I just slide the airbox clamps back over the carb mouth so there is no risk of losing parts into the belly pan. I install a 5/16" fuel shut off valve in place of the plastic joiner in the supply line to the pump. Usually located above the brake caliper and behind the reverse beeper (on the Ventures). Less fuel loss and it keeps it from flooding the crank when the needles and seats eventually start leaking. Also makes it harder to steal. I ride in very low temperatures so reduce the risk of busting pull cords I often add a primer tee just after the shut off valve and connect the primer lines to the sync ports on the carbs. I only pull the airbox if I am changing the fuel lines and never had to pull the secondary for the carb or airbox removal. To install the carbs I rotate them into the intake boots first and then just use my fingers to work just the bottom of the mag side boot on to the airbox and make sure the sides and top are clear and not tucked inside anywhere. tipping the airbox up a bit helps. Then I just pull the air box forward with one hand putting pressure on the boot while pulling up on the two top tabs as needed. It usually pops right on. Just remember to install the airbox clamp before working the pto side carb in the same manner or you'll risk popping the mag side off in the process. This works for me and has saved many a F-bomb.