Wont' start, and how do I get the velocity stacks back on...

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Falaholic

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Yea, won't start. Its the gas. It sat for 6-8 months. Could have sworn I used ethanol free.
Tank is 1/4 full, and rusting. I'm seeing surface rust in the throat of the tank and at the bottom.
Bike cranks over, doesn't fire. Starter fluid will get it running and will only stay running on starter fluid.

I managed to take the air box out; dropped a screw that had me having to take it out. Problem is, the grommets won't go back over the carbs. Is there a special way to do this. Everytime I think they popped back on, I shine a flashlight through the airbox and see light coming out from the bike frame.

How should I proceed with the fuel issue? Do I disconnect the fuel line going to the carbs, and use the pump to pump out the fuel? do I siphon the gas, and fill it back up with fresh ethanol free gas and treat it with Seafoam? Am I going to have to disassemble the carbs to resolve this issue?


Thank you
 
Sounds like you need to replace the old airbox boots. They get old and hard and make it more difficult to get them back on the carbs and stay on. They aren't terribly expensive and I usually keep them on hand (though I am currently out).
 
I've posted about the method I've used to "seat" the airbox. Sean, is of-course correct, replacing them is probably what you need to-do. However, you may wish to try some things, to replace the airbox in-position on-top of the carb rack.

Some people suggest throwing the boots into boiling water, and then re-fitting them onto the airbox, and the airbox & boots onto the carbs. Boiling them will soften them-up, and hopefully, allow them to re-seat. The thing is, they cool quickly, and you really need to replace the boots, and to try for seating the airbox & boots assy. quickly.

Here's another method I use, if I need-to. There are several products you can use for lubing the boots to allow everything to slip-together easier.

One is silicone spray, Because of the nature of the product, silicone spray is naturally a lubricant which can assist airbox replacement. Use it on the inside of the boots, and the 'lip' where the carb airhorns make contact with the airbox rubbers. Do not over-apply the spray.

Another often-used product is WD-40. It's used in the same application method as the silicone spray. You don't need to have the spray dripping-off the carbs, just ensure that where the boots and the carb touch are both wet.

The third product, and the one I like to use, is water-soluble jelly, like KY. It comes in a tube, squeeze it onto the rubbers, use your finger to 'grease' the inside and the rubber 'lip,' and the edge of the carb body where it contacts the rubber.

Now, here's my favorite part of the installation, how-to 'seat' the airbox. Hopefully, you still have your centerstand, if you don't, either have it in a workbench front-wheel vise, or have a friend holding your bike upright.

Carefully place the airbox onto the carb rack, you should be able to very accurately align the rubbers with the carb mouths. Misalignment here will make it difficult if not impossible to easily insert the carb boots over the carbs! Use one of the lubricants as mentioned.

Now, carefully climb atop the bike, making sure you don't disturb the alignment of the airbox. With your feet on the footpegs, scoot-up and rest your feet onto the engine front cases. Now sit-down onto the airbox, and you should feel and hear distinct 'pops' as the boots slip-down onto the carbs. You have just "seated" your carbs.

Dismount, and ensure that your boots are fully-seated onto the carbs. Tighten up all the clamps. good to-go!
 
Rust is another issue.

Because it's so-problematic, a rusty tank is one of those things which just cannot be overlooked, it certainly isn't going to 'go-away.' The small particulate material from the rust will constantly clog your carbs' pilot jets, necessitating repeated carb removals and splitting the carbs into two pairs, to be able to access the jet block, to remove the jet block, and to remove/clean the pilot jets, and anywhere-else the rust has lodged. If you are removing the jet block, buy jet block gaskets because these usually will tear when you remove the jet blocks. You need four. #35, here:
https://www.ronayers.com/oemparts/a/yam/50045c0ef8700209bc7942f3/carburetor
The pilot jets (#42) are cheap, and you save having to try to find something small-enough to clean them, the holes are really-small. I usually use a pin vise and a tiny SS wire about an inch long, with a lot of care. What you need to do, is to scour your tank, and to use one of the coating products on the market. You might find a local jobber by you to do it, maybe a radiator shop. Be aware that the coating products have to be used exactly as-described, because to try for shortcuts will inevitably result in a botched-job, and will require you to scour-out the tank again, and to repeat everything.

There are plenty of threads on here about how-to scour the inside of the tank, and then seal the tank. POR 15 is one method, Red Kote, is another, another is KREEM, for sealant. Heed the warning above. Dannymax and Sean Morley will confirm, improperly-using a coating product will just create more problems. I'm sure that if you didn't want to try the procedure, either one of them would be happy to do it for you. Don't be surprised though if upon receipt of your tank, they inform you, "the tank is no-good." I'll tell you what my friend who is a Yamaha dealership mechanic told me: "don't mess-around with trying to clean and to seal a rusted tank. Bite the bullet, buy a new one. It will save you time and money in the long-run." He's been a Yamaha dealership mechanic since before the VMax Gen 1 was released, he's built hot-rod versions, repaired many 2nd gears, and has cleaned many a VMax carb rack.

I've used vinegar to remove tank rust, just make sure that you remove the tank fuel sender, and replace it with a block-off plate, use the base of the fuel sender unit to accurately drill the bolt holes. Smear it with some Permatex gasket sealer, and bolt it on. Several days, you can drain the vinegar, or whatever rust remover you choose, to see how it's doing. Be aware some more-caustic rust removers may only require a much-shorter timeframe! Evaporust is another popular method.

Adding some metal to the tank with the rust remover, and then agitating the tank repeatedly is another method to break-up the rust. I've read of someone wrapping the tank in heavy carpeting, secured with duct tape, and then inserting the 'ball' into a dryer, and putting it on 'air-dry.' No heat, no liquid in the tank. I've never tried this, and the machine does all the work. Probably a soak session once the dryer method has removed most of the rust, is how to proceed. If you choose this method, take before & after pics, and post 'em.

You can also try electrolysis, there are many articles on the internet about this. Here's one, you can find others on youtube.
https://www.motorcyclezombies.com/rebuild-tune-motorcycle/carbs-fuel-air/remove-rust-gas-tank/

Bottom line, you need to do something to remove the rust. Many people use some type of sealant, do your internet research, come-up with a plan, and follow it.
 
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Thank you guys. Does anyone by chance have the part numbers for the boot grommets.
Now regarding the fueling issue, do I have to pull out the carbs?
 

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