The two rubber hoses on front (bottom) of gas tank....where do they go? Are they needed?

Hi guys, I recently did a valve adjustment to my 5th Gen and when I finally got everything together I noticed that I could not find where the other ends the two rubber hoses connect. I have removed the PAIR system and I have blocked off the valve cover with the Toro custom aluminium plates. I think one hose is some sort of pressure release drain??? But I have no idea where the other one goes. I looked in the shop manual and I do not have a evap/charcoal canister (where I think it gets connect to). If anyone can give me some insight on this they that would be greatly appreciated.

 

Dino - I'm away on business for a few days, but in the unlikely event you don't get this figured out before the weekend, give me a call and we'll see if we can work through it.

 

If it's not a Calif. model. I think they are vent and overflow tubes. One of them connects to a white fitting behind the frame left side rear of the tank.

 

Here's a pic of those two hoses on my 6th gen. Dino. The hose on the left in the pic (the smaller of the two) is the gas tank vent hose. On the 6th gen. bikes that hose connects to the EVAP Canister. Since your bike doesn't have the EVAP Canister that hose should simply vent to open air. As the fuel level in your gas tank goes down,air has to replace the space above the fuel and that hose is where the air gets in. On my 6th gen. the gas tank vent hose routes down the right side of the bike and is connected to the EVAP Canister. I removed my EVAP Canister and loosely cable-tied that vent hose to the frame.


The hose on the right in the pic (the larger of the two) is the fuel overflow hose. If you open your gas cap and look closely you'll see a small drain hole to one side of the opening where you fill your gas tank. That's the fuel overflow drain hole and that port is connected to the hose on the right in my pic. You MUST have that fuel overflow hose connected Dino. If you overfill your gas tank and that hose isn't connected,that gas will spill right onto the top of your hot engine. That would definitely NOT be a good thing. On my 6th gen. the fuel overflow hose routes down the left side of the bike and is held in a small bracket along with several other hoses on the left side of the oil pan.

 

I was going to post the exact same thing but Stosh beat me to it.

Stosh, where did you source that CF cover for the gas cap? I'm assuming it is just held on by adhesive of some sort?

 

I got that C/F gas cap cover from the Parts Unlimited catalog Meat. Dennis Kirk's got them too. It's made by Pro Grip. It's only C/F look though,it's not the real thing. It has a nice raised gel coating on it that really gives it some three dimensional depth. It has 3M adhesive on the back of it,just peel off the backing paper,place,and press. Simple as that. I've had mine on the bike for maybe 4 or 5 years now and the finish is really holding up well.

 

Hey guys, im putting my bike back together (1998) and my vent hose is just dangling there, but the end of it is enlarged like it was connected to something at one point. I cant find any empty nipples anywhere. Any ideas?

Also, there are 4 hoses, 2 on each side, of the lower airbox. They appear to just be plugged? Whats the purpose of a vacuum hose that leads to a dead end????

Thanks

 

I guess ill just put it together and leave these hoses dangling?

 

Picture please Bat! hoto:

There are a lot of hoses beneath your fuel tank.

BTW Bat,part number 16 in this first pic is your tank vent hose. Part number 20 is a plastic pipe union,it joins the formed hose (part number 16) to the straight hose (part number 40). That fitting and extension hose might be missing on your bike,could be why the end on your tank vent hose is enlarged.

 

Thanks for the diagram, where did you get it? LOL
Couple questions...

1. Where does the other end of hose #40 go? If it just dangles, ill be ok as i dont think a check valve is required.
2. the other hose in question plugs into the lower airbox near where #14 is in that diagram. There are 2 hoses on each side of the box, and the 1 i mentioned is broken off the box but the nipple is still inside the hose. All 4 of these appear to be dead ends because the one thats broken off is solid, it doesnt have a hole in it like a normal vac nipple. Im curious what the purpose of a vacuum hose is if its not sucking on a selonoid/diaphram/etc

Thanks

 

On my 6th gen. I've got that tank vent hose running down the left side of the bike and it's loosely tied off with the rest of the drain hoses. Just make sure that tank vent hose doesn't get pinched Bat and you should be good to go.

Okay now to tackle those infamous "4 Vacuum Hoses To Nowhere".
According to my Service Manual those 4 vacuum hoses that are plugged into the sides of your airbox are used as test ports for synchronizing the starter valves on your throttle bodies. You simply unplug those vacuum hoses from the plugged ports on the sides of the airbox,plug them into a vacuum guages/manometer,and then make any necessary adjustments you might need to the starter valves. My guess is that they were located there to make it easy for you to gain access to them should you need to make any adjustments. Just make sure the ends of those vacuum hoses are capped off tight Bat or you'll have yourself a vacuum leak there.

 

My first experience with my VFR had to do with that damned overflow/drain hose. I brought the bike home in the back of my truck from five hours away, and it rained the whole time. I got it home, unloaded it, and began to dry it off. Apparently some crap clogged that drain hose and when I decided to open the tank for kicks and giggles the entire gas cap recess was full of water... it all went in the tank. I used an air hose to clear the line, dumped dry gas in the tank, then siphoned all the gas out of it.

 

Awesome stosh, thanks

 

Very helpful post guys.

I was working on my cold weather idle and I removed the airbox. What a nightmare. I was unsure about the hose locations but your diagrams have confirmed all is good.

What a bastard to get on and off (the airbox).

P.S. I was also perplexed about the 4 hoses to nowhere.... Thanks for clearing up the mystery.

 

Tanks and tubes!

Guys,
great detail and lots of help - thanks.
However, I've a question. Does connector 7 on tube 15 (tank diagram) really connect to the item 14 in the airbox diagram? The tube is certainly long enough but it appears to connect the vacuum system to the tank.......

any confirmation or a photo would be very welcome - getting the end of a very long problem (replacing wiring loom which was made more difficult by a complete seized engine mounting bolt) and this is the last problem to solve.

thanks
Phil

 

FYI I had one of my hoses wrong and in about a month the bike died. Was running rich apparently because of this.

Take care with this.

I am never ever removing my airbox EVER again

 

A shop manual is really good for getting the airbox off and back on again.