Hi gang,
I've had a problem with the vacuum pump since i got my '51 2R5. It's got a champion motor, with the dual action fuel/vacuum pump. When I got the engine running the fuel pump worked great, but no vacuum. I rebuilt the pump with alcohol resistant components, put it back together, had vacuum for a few seconds, then it stopped. A bit of troubleshooting later, i found the port in the intake was plugged, so when i cleaned it out, I had vacuum (swipers) until the hill. So then the vacuum pump wasn't working again. When I took it apart the first time, I was very careful to photograph every step to ensure I put it back together the right way, including using the diagrams in the book. I rebuilt it a second time (new parts... again), and had vacuum for a few seconds, then it died again. This time while taking it apart, i was careful to notice that the pusher arm had come off the vacuum diaphragm rod. So i re-mounted it, put it back on, it worked for a few seconds, then stopped. I thought maybe the vacuum pump is old and worn, so I found a brand new NOS dual action pump on fleabay, got it, rebuilt it with new innards, put it on, and the exact same thing. I'd have vacuum for a few seconds, then it would stop, and upon disassembly, the arm would be off. This has happened now a total of 7 times (although i've only rebuilt the pumps with new parts 3 times...the other times just put the arm back in the diaphragm rod) Looking at the pusher arms which are attached to the cam follower, the new one looks just as good as the old one, a nice little notch where the pusher arm meets up with the diaphragm rod. It just won't stay in there when the engine starts running. I sharpened the corners of the groove on the old pump to see if the components were too rounded, but to no avail. The build sheet indicates the truck came with a dual action fuel/vacuum pump, i verified the part numbers in my book, and made sure the new one I purchased was the same number as the book and the old one. I can't for the life of me figure out how to make this silly thing work. I emailed Chuck at stude-intl to see if he's had complaints after rebuilds, and he said no. So I'm coming here, hat in hands, hoping someone has had a similar problem. Actually I'm not hoping ill-will on anybody, i am hoping someone who has had the same problem has a fix. Thanks in advance for your help
chris
I've had a problem with the vacuum pump since i got my '51 2R5. It's got a champion motor, with the dual action fuel/vacuum pump. When I got the engine running the fuel pump worked great, but no vacuum. I rebuilt the pump with alcohol resistant components, put it back together, had vacuum for a few seconds, then it stopped. A bit of troubleshooting later, i found the port in the intake was plugged, so when i cleaned it out, I had vacuum (swipers) until the hill. So then the vacuum pump wasn't working again. When I took it apart the first time, I was very careful to photograph every step to ensure I put it back together the right way, including using the diagrams in the book. I rebuilt it a second time (new parts... again), and had vacuum for a few seconds, then it died again. This time while taking it apart, i was careful to notice that the pusher arm had come off the vacuum diaphragm rod. So i re-mounted it, put it back on, it worked for a few seconds, then stopped. I thought maybe the vacuum pump is old and worn, so I found a brand new NOS dual action pump on fleabay, got it, rebuilt it with new innards, put it on, and the exact same thing. I'd have vacuum for a few seconds, then it would stop, and upon disassembly, the arm would be off. This has happened now a total of 7 times (although i've only rebuilt the pumps with new parts 3 times...the other times just put the arm back in the diaphragm rod) Looking at the pusher arms which are attached to the cam follower, the new one looks just as good as the old one, a nice little notch where the pusher arm meets up with the diaphragm rod. It just won't stay in there when the engine starts running. I sharpened the corners of the groove on the old pump to see if the components were too rounded, but to no avail. The build sheet indicates the truck came with a dual action fuel/vacuum pump, i verified the part numbers in my book, and made sure the new one I purchased was the same number as the book and the old one. I can't for the life of me figure out how to make this silly thing work. I emailed Chuck at stude-intl to see if he's had complaints after rebuilds, and he said no. So I'm coming here, hat in hands, hoping someone has had a similar problem. Actually I'm not hoping ill-will on anybody, i am hoping someone who has had the same problem has a fix. Thanks in advance for your help
chris