Changing An Automatic Flywheel Without Removing the Transmission

[Dejure]

A few decades back, I helped a buddy run his farm, which was two 100 acre plus fields under irrigation circles, about 15 acres of apples, and custom work (i.e., baling hay and harrowbedding the alfalfa out of the field). This, all, translates to "in-way-over-my-head" stuff, I'd never farmed before.

As it tends to go, even with smaller farms, working the farm meant working with a lot of equipment. Things like a swather a harrowbed (picks up bales and makes small haystacks), three balers, an orchard mower and sprayer, four tractors, a spreader (compost tosser), and several different cars and trucks.

One of the farm vehicles was a 73 square body with a 454. My buddy was tackling swapping out the flywheel of its automatic transmission when I left for the fields to check the circles, feed the 17 cattle, change the water in the orchard, and so on. I headed out at daylight, and it was nearing dark, when I returned. My buddy was still under the truck, and had gotten nowhere, slowly.

I crawled under the truck to see if I could help speed things up, if only to play gofer.

Aside the fun involved in disconnecting linkage and such, the farm lacked equipment by which the transmission could be, easily or safely, pulled. To get around that, my buddy just released the drive-line, then slid the transmission back on the bolts. That gave him just enough room to get a teasing view of the few flywheel bolts visible at the bottom of the flywheel.

Very much aware of my extreme ignorance of automatic transmissions, and because I presumed my buddy's decades of working on all manner of farm equipment had given him significant knowledge about the project he was undertaking, I kept my mouth shut, if only to hide at least a bit of my ignorance.

After about 20 minutes or so, and aware this was where I'd left him hours earlier, it became obvious this was going to turn into a career, unless something different was tried.

Finally, I asked why we couldn't just snug the transmission up again, temporarily install longer bolts on top, remove the lower bolts then slide t he transmission back on the longer bolts, to gain extra room needed to access and remove the bolts holding the flywheel on?

Hours in, my buddy was desperate enough he was even willing to listen to the village idiot. We went the longer bolt route and had the flywheel swapped out, and the transmission bolted back onto the housing within an hour.

In addition to getting the load hauler going again, one of the positive things out of this adventure was, I became proficient at operating the screwdriver/prybar we used to rotate and secure the flywheel, during bolt removal and re-installation.

 

[donnieray]

Great job! Congrats.

 

[Ricko1966]

You use 2 long starter bolts one on each side to replace 2 bolts. The flex plate can be turned and all three bolt positions loosened turning the crank with a wrench on the torque converter bolts.You can stick a deep socket and breaker bar on a converter bolt while you loosen the ne xt converter bolt the socket will rest on the block and keep the crank from turning. You loosen the first one,then tighten it back but not real tight,use your wrench to turn so you can see the next 2 one far left one on far right loosen and remove the one on far left use your wrench on far right to pull the crank around. When you can see both again loosen and remove far left,put your wrench on the one on right smack with the palm of your hand. That one will break loose, loosen and remove.This is my go to on flex plate R+R.

 

[Bextreme04]

I had to do this on my LS when I forgot to torque the flywheel bolts on a 5.2 to 6.2 swap. I bought 4-1/2" long bolts from the hardware store, swapped them out on two top bolts and two side bolts. I was able to slide the 6L80 and transfer case back enough to remove the bolts, add red loctite, then install and torque to spec with my 1/2" torque wrench.

 

[SquareRoot]

Flexplate-Flywheel, Tomato-Tomato. Sorry, it's my OCD.