Leak in my fantastic fan installation

[devonian19]

Hi I'm building a campervan out of a ford transit lwb high top, I have installed a fantastic fan vent 2250 and it has a very small leak in one of the corners I've mended it (or thought I had) and the leak has re-appeared inside weeks later. This process has been repeated many times. Now I have added a lot of sika flex to try and seal any holes on the outside and now cannot find any holes or any place where the water could possibly ingress, I am totally stumped. I need advice do I try and find the leak through hose pipe experimentation and fix it with more sika flex silicone or remove the fan and start again? I don't understand why it is leaking nor what I can do differently if I re-do it however.

(ps I cannot see any cracks in the fantastic fan vent plastic either)

 

[Figaro]

Water can track along so weak point may not be where it shows.
You may need to remove and start again.

 

[MANGOFORTH]

Have you tried rubbing it with a fish finger ?

 

[two]

I'd take it apart and start again. Whilst water will always fall, it doesn't usually do so vertically. Finding the source will be a difficult and thankless task. At least you are now aware of the need for generous sealing (from the top). Better luck next time!

 

[pappajohn]

Remove the hinge from the base and put a bead of sealer along the line between flat and upright plastic parts then refit the hinge before it cures.
There may be a crack under the hinge that you can't see.
Also, take out the screw in the red circle and squirt a bit of sealer in the hole then refit.

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[devonian19]

Remove the hinge from the base and put a bead of sealer along the line between flat and upright plastic parts then refit the hinge before it cures.
There may be a crack under the hinge that you can't see.
Also, take out the screw in the red circle and squirt a bit of sealer in the hole then refit.

The screw head has sealer on top of it I'd started using clear sikaflex around there so it may not be easy to see. Also I have already removed the hinge and had a look and found nothing. I could add a bead of sealer where you said but cannot see any holes there I've even pushed the plastic with a tool to see if a hole opens up and it doesn't

 

[Lumpy]

I experienced a leak like this when I fitted a rooflight, ended up taking it out and discovered I had over tightend the clamping fixings so cleaned everything up and re fitted, making sure not to squeeze all of the sealant out but leaving around 2 to 4mm of sealant in the joint. Never leaked again. Hope you find a way to fix your leak.