chimney leaks in rain, why?

[paulmars]

All the screws are sealed on the outside with silicone sealant. Also, a bead of silicone on top that support piece that twists around the pipe. Pipes are installed in proper direction, so its not leaking in the pipe assemble joints. Every pipe seam in the garage drips water when it rains.

I cant figure out where it comes in. Id rather not get up there with a hose. It only leaks when there is a lot of rain. Either very hard rain or just a long rain.

Ideas?

pics here: chimney leaks in rain, why? - https://www.diychatroom.com/f17/chimney-leaks-rain-why-685761/#post6135701

tks,
pa

 

[SimonG]

What's it attached to? Looks like single wall vitreous enamel. Why not go straight up through roof?

 

[SJB060685]

This installation looks familiar. Are you an American?
Are you sure the joins are the right way?
Also is it vitreous enamel? As this is not water tight I believe

 

[snowhead]

I'd guess it's running down the outside of the vertical pipe and getting in on one of the 2 joints the corner / elbow where it's factory formed.
It looks like that corner piece elbow is adjustable