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tips on dynaflow "torque ball" seal replacement

Toque ball seal replacement. On this 55 dynaflow. Dynaflows tend to leak no matter what. i recall seeing a drip pan under a 50's buick on the dealer show room floor in a vintage photo.. some ways you can prevent/cut down on that when the transmission gets resealed is check for all blind threaded holes and add sealer and its extremely important that all gasket mating surfaces are deburred.. Probably the most common leak is at the torque ball. Kit comes with the rear seal plate and shims. First you have to polish the seal journal yoke. In the pic, you can see how years of contamination have turned the surface to hamburger. the seal itself also acts as an abrasive as the years went by. It needs to be polished like chrome like i spent an hour doing and sanding it up to 2k grit before putting it onto the polishing wheel.. If theres heavy pitting or scratches, they need to be filled with JB weld (or any other method of choice.) and then polished the same way. Then you have to experiment with stacking the shims in between that plate and the one behind it. Be sure you debur the edges on all these plates.. It took me 3 tries to get the preload right on this one. Take it apart stack shim gaskets check the preload and then take it back apart. Each time. As you tighten the joint down, use a rubber mallet and tap the joint around to be sure everything is centered while u tighten it... Book tells You to use a spring type torque wrench. There's one around here but I havnt seen it in a long time, so real quick I made a special tool. You want to check the preload from 14 3/8" back from the U joint end. I put a hose clamp on my new tool so it doesnt go in too far... You want 20 to 25 pounds of preload. Once I got that, I took it back apart yet again and coated both sides of all the gaskets with that really wattery permatex "make a gasket" or "indian head" sealer... Its a Brown light weight sealer that won't add to gasket thickness or contaminate the inside of the transmission. at the end of the day, seal preload isnt really a science. its better too tight than too loose. if its too loose it can actually act as a pump to pull the fluid out the trans. Theres also a rubber boot that covers the whole joint that you install at the very end, that I didn't take a picture of... if you can help it, look for an NOS front torque tube seal (installs in end of torque tube facing the transmission). the new replacements seals they sell dont have a protective lip that sticks up to support the weight of the propellor shaft laying on it prior to stabbing the trans, otherwise its a lot of weight that can potentially damage the seal before you even get a chance to get it together. not a bad idea to also drill a hole in the torque tube at the bottom near the rear end in case it ever leaks later on down the road, it'll help keep the rear end from filling with trans fluid




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