Tank pressure

Should my gas tank let out a scream like it's about to explode every time I open it?. There seems to a lot of pressure built up when I open to refill the tank, is this normal? Thanks

Nope. The vent or charcoal canister system is blocked somehow I'd guess.

Pete Roper wrote:

Nope. The vent or charcoal canister system is blocked somehow I'd guess.

Thank Pete, here is what I've done but it had pressure before doing this. Evap removed, tip valve and breather along with plugs to vent lines from tank open to atmosphere.

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I had a similar problem on my sport where the water was not draining away and when you open the petrol cap water poured into the tank, may be the same type of problem.

it was the metal spigot tube, theres one for water disposal and one for tank pressure/fuel venting - it needs to be cleared (i.e drilled out) if it's blocked.

Afraid it's a tank off for this to check

BrianD wrote:

it was the metal spigot tube, theres one for water disposal and one for tank pressure/fuel venting - it needs to be cleared (i.e drilled out) if it's blocked.

I had a similar problem with a Breva 1100 tank years ago.  The metal spigot tube is not straight, so a normal drill cannot be used to clear it.

I used a short piece of speedometer cable inner on the end of a battery drill to clear it.  It took some time, but the water problem vanished.

Those 2 clear hoses should be closed, looks like the blind plugs are lost.
They're airbox drains, been open dust or whatever small enough can be sucked in the airbox.

Picked up a new 2017 last fall - the first time I opened the fuel cap a gush of gas blew up into my face. The tank seems to be under lots of pressure, worse when empty. If open the cap a few hours later the pressure has built up again, this can go on for a few days even if the bike is sitting unused. The dealer “rerouted” some of the lines and that seems to have helped somewhat. Still under pressure tho.
Was reading a thread [You must be registered and logged in to see this link.] about this issue. Seems like lots of information that might not be accurate. I removed the “non return valve” (in the picture). When I disconnected the hose that runs into the valve it ether sucked or blew air. Connected the two hoses and haven’t had any tank pressure since. My question is what issues can I anticipate by having this valve removed. The bike is still under warranty for another year, not comfortable removing the canister until the warranty is done.
The paint on the fuel tank has begun to show signs of cracking, After reading “My Life In Bikes” by Dave Richardson I’m sure Moto Guzzi won’t replace the tank, but I am going to run that by the dealer anyway.
PS: the right side of the motor looks much better without the bright blue & orange valve hanging off. Ha Ha![You must be registered and logged in to see this image.]

My 2014 would always make noises after a ride. No big pressure issues but if I opened the tank the noise would stop. Best thing I ever did was take the stupid canister off and throw it away. I connected one of the lines between the two throttle bodies. I got rid of the blue and orange valve which really may have been the issue.
If the paint on the tank is cracking it could be related to the pressure or to ethanol gas. Do you use ethanol gas in Edmonton? I would push for the dealer to replace your tank either way. I’ve heard of others getting a new tank. Most times in the States, it about always an ethanol issue expanding the tank. Happened to me a year after buying mine. I got a replacement tank and lined it with Caswell tank epoxy. Been fine ever since but I just about always run non ethanol gas as I moved to a state where it’s available.

Thank you John A for the reply. I have only used ethanol a few times when I first got the bike. For the past 3000K it's been ethanol free. Finding ethanol free isn't a problem in Edmonton, many Shell stations have it. Haven't had it on a road trip yet so don't know what to expect for fuel choices.
Did contact Petro Canada about the amount of fuel (regular to premium) between the pump switching device and the nozzle but they were dismissive suggesting that the amount would be insignificant - I disagree due to the 16 liter capacity of this bike and a previous bike.
Had a 2007 Norge that I bought used, the tank had bubbled a wee bit, it was very difficult to get it seated after removal, I suspect that the tank had swelled causing the problem.

Same issue with my "new" 2017 (excessive tank pressure, fuel blowing up into your face, hairline cracks in the tank, and poor hot start behavior). I preferred to keep the system intact for emissions reasons, but had to shitcan the setup after I couldn't find anything that required "fixing" (the problem appeared to be the canister itself). Significantly better results with the tank ventilation routed as per the rest of the world, although I opted to retain the separate hoses for tank ventilation and water drain.

As also mentioned, ethanol is another potential problem. Keep the level low if possible after rides (fill at the beginning) and drain the tank if it's going to sit.

One major caveat! If you live with children and have a garage attached to your house, consider running a hose outside of the garage, and temporarily connecting it to the tank vent after you park the bike. Some of the gasoline fumes will otherwise enter the home, and may be detrimental for the young ones over time.

avgpetro wrote:

Those 2 clear hoses should be closed, looks like the blind plugs are lost.
They're airbox drains, been open dust or whatever small enough can be sucked in the airbox.

No, airbox drain is only one of the clear hoses. The other one is the drain of the plastic crap where the battery sits in. It is attached to a fitting at the inner left corner (deepest point) and can be left open.

Just a thought, there's lots of talk of tank pressure, but in my experience it's a lack of pressure (i.e. it sucks!).

If you have pressure in the tank, then it's a different issue.

Solojoe wrote:

My question is what issues can I anticipate by having this valve removed. The bike is still under warranty for another year, not comfortable removing the canister until the warranty is done.

That stuff is only on North American bikes. For California regs. Just rip it all off.