In last month's article, we had just removed the Dynaflow transmission from our '53 Buick Roadmaster 2 door Riviera hardtop. After checking casting numbers, we found that it was the correct "twin turbine" for the 1953 50 and 70 V-8 series. The Dynaflow for the 40 (Special) series has differences in the converter stator, output shaft, rear bearing, speedometer gear and the 50-70 Series has an access hole for adjustment of the valve operating rod without removing the tail shaft. Our transmission leaked badly from the front and rear seals, and had no park. We had test-driven it before removing the transmission, and it had performed well in all ranges. With the transmission out, we took it to the transmission shop for rebuilding. Soon, we received a call and was told that something had destroyed the pump and pump plate. The usual cause for this was extreme end play in the crank shaft. We had just rebuilt the engine, so there was no way to know how much end play that we had before the rebuild, but now it was .004. The Buick manual lists .004-.008 as tolerance, so that wasn't the problem. The converter pump is bolted to the flywheel so that it rotates whenever the engine is running, so we checked the flywheel to see if it was warped. If so, it could pound on the pump. We put a dial indicator on the block with the plunger touching the flywheel and rotated the engine around using a remote starter switch. The flywheel was warped .072! It might not have been enough to cause the problem, but it would contribute to it. There was nothing in any of the manuals about this, so here is where knowledgeable old car buddies come in handy.
We called Northwest Transmission Parts and spoke with John and Rusty. They spent a lot of time with us going though their books to help us find the cause of our problem. We started with the crank and worked back. Our crank was correct, and the flywheel was on correctly. Flywheels had different part numbers for the '53 and '54, but the only difference is in the teeth. In the '53, they were beveled, and in the '54s, they were square. Buick found that the starter showed less wear with the square teeth. They also found a potential problem that would take place at installation, and that was when the transmission is bolted to the block, there must be clearance between the torque converter and the flywheel of between 1/8" and 3/16". If the torque converter can't be pushed back to give this clearance, it will destroy the pump quickly.
We called Jim and Gib at Buick World, and found the parts we needed including a good '54 flywheel, which we tested using our dial indicator. It checked out .008 out, which is fine. Our internal parts were ordered from Northwest Transmission Parts and subsequently delivered to Donnie at Quality Transmission here in Chattanooga. The pump, pump plate and all gaskets were replaced, as well as a new torque ball kit. We also discovered a clip that Buick called a fastener, lying in our transmission oil pan. It connects the valve operating rod to the lever that goes on the linkage inside the transmission.
After rebuilding, we were now ready to put the transmission back in the car. Using our transmission jack to position the transmission, we fitted it to the engine block. Our torque tube assembly was already pulled back and held with ratchet straps, so the transmission slipped right in. We aligned each side with the left and right dowel pins on the block. These are important, because they keep the transmission from moving back and forth, which could also cause wear on the pump. As we bolted the transmission to the block, we saw that we did not have the flywheel-to-torque converter clearance we needed. They were tight against each other. We had checked everything from the crankshaft to the transmission, and there was no adjustment to get our needed space.
We needed to find at least 1/8" clearance from our flywheel to torque converter. After telephone conferences with our restoration team, we decided to use 1/8" spacers at all transmission-to-engine bolts. After they were installed, we finally had our clearance! This would serve until we could make a spacer plate later on. We installed the transmission in reverse order of our removal sequence (see Driving Old Cars, Issue #3, 2005) and installed a new thrust pad and transmission mount. A new torque tube seal was installed, turning the spring side toward the transmission. This seal keeps fluid from running down the torque tube.
With the transmission back in, we hooked up our shifting linkage. Before adjusting, we added our fluid. This transmission uses the new Dexron III fluid and can be filled in the normal way under the hood at the filler tube. It takes 10 quarts. We put 5 quarts in, then started the car and immediately added the other 5 quarts. With the fluid in, we were ready to adjust the shifting linkage. The detent is in the shifter arm, not in the transmission. To adjust, we warmed up the car to normal operating temperature and checked the transmission fluid, then checked our Park with the Buick on a steep grade. It immediately made a ratcheting sound, indicating it was not engaged in Park. To externally adjust the shifting rod, we placed the lever in Park and disconnected the lower shift rod from the shift idler lever on the transmission, then we pulled forward on the shift rod and let the car move slightly. This locked into Park, so we knew Park worked. We then moved the lever all the way to the rear of the car and we had Reverse. Our problem had been that we couldn't get Park if we had Reverse, and vise versa. We set the adjustment on the adjustment rod so that at approximately 600 RPM with the shift lever's tip of the dial pointer, midway between "N" and "D", the transmission engaged. We then reattached our linkage and still had a ratcheting noise in park. All other ranges were fine. This indicated a bent transmission shift lever, or the need for an internal control valve and operating rod adjustment. To do this, remove the round cover plate on the transmission and adjust the rod. We buttoned everything else up and went for a test drive. All ranges pulled strong and no leaks were apparent. We are hearing what seems to be some noise at the pump. We might have to increase our spacer distance. In an upcoming article, we will make a permanent spacer plate in the shape of the bell housing, and give you a final on any problems. Patience and persistence are essential to car building. Look for our new article, "Inside the Shop" coming soon. Keep 'em driving!