Fuel Cap Breather

[fazersharp]

[quote author=locksmith link=topic=21819.msg252499#msg252499 date=1487063361]
As a lay-man, I would think a blocked breather would cause the tank to gain a negative pressure so that when you open the filler cap a loud hiss of air rushing in would be apparent. Is that the case?

I think if it was totally blocked it would do that, but if it was that bad it would also run like shite or even cut out.
Once it's started, eventually, it appears to run okay though. I'm mainly only doing 6 mile runs to and from work so it may not even be far enough to build up a big vacuum.
To be honest, i'm just trying everything, one thing at a time, until i figure it out.
I might try blowing air up from the bottom of the tank which will be easier to feel if it's blocked or not. I can't see why it should be though as it all looks like a sealed unit once the cap is locked down.
[/quote]
Have you tried taking it out for a dam good thrashing