Any one know the internal measurement of the top hose on a standard impreza rad, need to order a temp gauge fitting and don't want to undo my hose just yet. thanks.

 

you might wanna say which year/model

 

whoops, 95 RA

 

I can't say for that model, but mine, a 98 UK car, was 38mm.

BUT: when I replaced my rad, I obviously had to remove the top hose from it. Under two days later, the top hose sprang a leak. Only a pinhole but CLOUDS of steam, very alarming.
Anyway, removing it for replacement showed that the inside looked like someone had taken a sharp scalpel to it, it was criss-crossed with tiny splits. I reckon manipulating it for removal caused one to go completely through

My advice: do your job, but with a NEW top hose.

Oh, and PLEASE, do a search on here for how to drain and refill WITHOUT airlocking Or your next post will be about headgasket failure

Under my username will find one.