I didn’t want to use the cooling pump’s barbed inlet or outlet. Fortunately, the cap is removable and made of aluminum so I cut the barbs off. A Y-shaped outlet was made from a 1-1/4” and two 3/4” tubes. The junction of the Y was slot shaped and a mandrel mounted in a hydraulic press was used to bend it round so that it would match the larger tube.
Two -12 ORB weld bungs were shortened on a lathe and a shoulder was machined to keep everything concentric during welding. In the picture below, the top bung is stock and the two at the bottom have been modified.
The Y was welded directly to the pump’s cap to keep packaging compact and to reduce the number of connections that might leak. The cap was replaced and the pump was mounted to check the outlet and to mock the inlet. When we tried to remove the cap to weld the inlet we couldn’t get it off.
Do’h #^#%#$! I had it on and off at least five times, but no matter what we tried we couldn’t remove it. It was late and with removal attempts quickly escalating, I decided that for the cap’s safety we should resign our efforts for the day. Abe was able to remove it in the morning. We’re not sure what the issue was, so we put some grease on the o-ring and compressed the split ring a couple of times.
The inlet uses a 1-1/2” tube for the radiator return and a 1” tube for the heater return. The heater line uses a standard AN fitting and the remaining three lines use clamshell couplers.
All of the weld bungs are female because if the cap were dropped the threads on a male bung might get damaged and wreck the entire part. This allows damaged male threads to be tossed and easily replaced. This “disposable male genitalia” approach is endorsed by the #MeToo Movement. External plumbing does have disadvantages!
A lot of effort went into the cap. If I need to replace the pump, I can simply swap the caps — assuming I can remove it LOL.
