Problem with vacuum

[kirkbie]

2003 90 HP 4 stroke OB Mercury.

Motor runs fine on earmuffs with vacuum line disconnected at T near a check valve. Once I hook this back up, it's very hard to start, idles rough and I get gas in my crank. Any help with this please?

 

[w2much]

Try this to start. Unhook the line at the T going to the check valve. Ask your buddy who did not chip in for gas last time out to suck on the line, then blow on the line.It should not operate in both directions, neither blowing or sucking. If he gets a mouth full of fuel, consider the debt partially paid.

 

[schematic]

sounds like a ruptured diaphragm in check valve