Granzon GH Series Radiator Pump Bridge Block (GY-M)

Block to GH360N screw issues w/resolution

I had a challenge getting the GY-M block to mount to my GH360N radiator. The supplied scews appeared to be too short. They would only bite like 1-2 threads and would not engage. I discovered that the countersink bores in the bridge were of an inconsitent depth. Additionally the GH360N thread inserts were deeper on one side than the other. The combination of these factors kept the screws from fitting. I ultimately purchased a counterbore bit to deepen the bores just a tad so the surface of the screws would be below the surface and purchased some M4x.7x25mm flathead screws. I shorted the M4 screws to ~22mm by grinding them down as 25mm is too long. The picture below shows the very slight difference in the bore depth before I deeped the hole. It was enough to prevent me from making connection with stock screws. Even then the stock screws didn't go but a few threads so I went with the longer screws. Happy to report everything is working great now.