Need a watery (low viscosity), clear epoxy

I'm looking to fill the valve shown through one of its inlet ports (ID = 1.1mm) so that the internal components will be "frozen" in place with a clear epoxy that I can examine post-teardown. I've tried standard cyanoacrylate, but it's much too viscous to wick in. I also can't force it in with pressure because I don't want to displace anything from its natural position. It feels like I almost need something close to the consistency of water dispensed from a syringe. Any suggestions/similar applications y'all have come across?