As part of a cooling upgrade to my MGB V8 roadster I had to shorten the standard water pump to make room for an electric fan on the back of the radiator. This turned out to be a quite tricky project, but I got there in the end and it has run successfully for over 1000 miles. I've made full engineering drawings if that's of interest? Here's a basic sketch of the modification to the Powertune pump WaterPump_Powertune_Old-New.pdf
Interesting. Do you have a picture of the water pump installed?
Scott
Sure, here you go. Ended up with 15mm clearance pump to fan.
Quote from: JD on February 13, 2026, 02:27:22 PMSure, here you go. Ended up with 15mm clearance pump to fan.
Very creative, nice work!
Scott
That does look helpful.
JIm
Nice work. My only concern is the question of how much does the shorter wheelbase between the bearings impact bearing life. 1,000 miles won't tell you anything about longevity.
That's a fair point, but bear in mind the original bearing was designed to withstand vibration and gyroscopic forces from what I would guess was a metal fan blade, which was quite a long way forward of the bearing. Whereas for my installation the main load is the auxiliary drive belt tension, which is in-plane with front ball bearing. I guess time will tell.