My Diesel Toyoya Hiace sucked up water through the air cleaner/filter and the engine jammed. Can I remove glow plugs to the cylinders to vaccum up the water then repace plugs?
Yes, you can do this, but you need a thin tube.. It also means knowing how the glow plug is located in the cylinder so you can work out how to manipulate the pipe to get to the water.
If that does not work, then removing injectors and turning over by hand first to get rid of most of the water, then with the starter to get rid of the last would also work.
Edit: you may or may not be lucky in terms of further damage, stopping an engine with hydraulic lock is very likely to have bent a connecting rod...