KitCarlson
Well-Known Member
About 30 years ago I replaced the A904 on my 66 273 Barracuda with a used unit from another 66. The original transmission had about 145K miles and 12 years of use before me. It slipped with a chatter, in very cold weather going up a steep hill. I lucked on to good transmission at the time, and made the swap, thinking to rebuild it in the future.
The internal pictures are of the transmission including valve body, are uncleaned, in the original state. It looks nearly dry, due to the 30 years of sitting. It has always been kept inside.
I found only a few worn items: tail shaft housing bushing, two rear clutch friction disks, a dark rear band friction color, and thrust washers #1 and #2. The rest of the parts were in specification, however all normal wear parts and seals were replaced.
A few simple tools were fabricated for the process. I used a couple 3/8" threaded rods and square tube to pull the pump. Alignment studs were made from two 3" 5/16"-18T bolts, for output shaft support and pump. The large bolt, C-channel and U bracket served to compress the the front clutch spring. The C-channel was used to bolt to the bell-housing for stability. Not show are hand tools as sockets and screwdrivers. A couple large 1/2" sockets were bolted together to drive out and install the tail shaft bushing. A freezer cooled the tail shaft bushing for easy installation. Four pieces of large punched angle irons were used to fabricate a frame, that bolted to the rear pan holes. The frame was used to hold the transmission vertical, in a 55 gallon plastic drum, for assembly of the rotating parts.
I found the hardest and most time consuming part was the cleaning. The assembly was fun and easy.
When doing a trial assembly to measure end play, it was discovered that the pump would not drop easily in the case without outer o-ring. While the two pump haves appeared aligned they were off a bit. The solution was to loosen the pump halves, insert in case for alignment and re-tighten bolts.
In setting the end play I used a a 0.062 #1, 0.042" #2 and a 0.068" between the shafts resulting in 0.024" end play. The worn thrust washers measured 0.022" at the wear surface on #2 and 0.040" on #1. The service manual suggested 0.062" on #1 and #2 but that resulted in nearly zero end play.
I found that the rear band setting specification for 1965-66' is 5 1/4" loose from 72"# tight. This is much looser that 727 and other later 904 transmissions. The rear band seemed tight on disassembly, so I wonder if that could have been a problem resulting in the rear clutch and band heat/wear issue. Perhaps there was maladjustment at some time.
I purchased a TransGo TF-2 kit. I may install it on the valve body of the spare transmission for testing, once this one proves to work with the standard VB.
I am welcome to any comments.
The internal pictures are of the transmission including valve body, are uncleaned, in the original state. It looks nearly dry, due to the 30 years of sitting. It has always been kept inside.
I found only a few worn items: tail shaft housing bushing, two rear clutch friction disks, a dark rear band friction color, and thrust washers #1 and #2. The rest of the parts were in specification, however all normal wear parts and seals were replaced.
A few simple tools were fabricated for the process. I used a couple 3/8" threaded rods and square tube to pull the pump. Alignment studs were made from two 3" 5/16"-18T bolts, for output shaft support and pump. The large bolt, C-channel and U bracket served to compress the the front clutch spring. The C-channel was used to bolt to the bell-housing for stability. Not show are hand tools as sockets and screwdrivers. A couple large 1/2" sockets were bolted together to drive out and install the tail shaft bushing. A freezer cooled the tail shaft bushing for easy installation. Four pieces of large punched angle irons were used to fabricate a frame, that bolted to the rear pan holes. The frame was used to hold the transmission vertical, in a 55 gallon plastic drum, for assembly of the rotating parts.
I found the hardest and most time consuming part was the cleaning. The assembly was fun and easy.
When doing a trial assembly to measure end play, it was discovered that the pump would not drop easily in the case without outer o-ring. While the two pump haves appeared aligned they were off a bit. The solution was to loosen the pump halves, insert in case for alignment and re-tighten bolts.
In setting the end play I used a a 0.062 #1, 0.042" #2 and a 0.068" between the shafts resulting in 0.024" end play. The worn thrust washers measured 0.022" at the wear surface on #2 and 0.040" on #1. The service manual suggested 0.062" on #1 and #2 but that resulted in nearly zero end play.
I found that the rear band setting specification for 1965-66' is 5 1/4" loose from 72"# tight. This is much looser that 727 and other later 904 transmissions. The rear band seemed tight on disassembly, so I wonder if that could have been a problem resulting in the rear clutch and band heat/wear issue. Perhaps there was maladjustment at some time.
I purchased a TransGo TF-2 kit. I may install it on the valve body of the spare transmission for testing, once this one proves to work with the standard VB.
I am welcome to any comments.
