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How far can TQ be pushed back when separated from flexplate?
#11
basstrix;283738 Wrote:
Pastel Blue;283696 Wrote:On my recent BB rebuild, I had the rotating assembly completely balanced from the harmonic balancer back to and including the flexplate. The flexplate is new as when I got the car,, the starter was chewing the teeth on the flexplate. Both needed replacing during the rebuild. We had to add some weight to the flexplate to complete the overall balancing.

When I sent my C-6 in to be rebuilt, I was the informed that the front pump required changing due to the torque converter pushing back on the pump causing permanent damage to the pump... I learned there was no play for the torque converter to move back and forth slightly which caused it to create additional transmission damage.

There should be some play allowed for between the torque converter and the flexplate, but I do t think it will be such that you can push it back far enough so that the studis are clear and the torque converter can be rotated, that would seem like excess play to me...

I haven't bolted up my rebuilt engine, new flexplate, rebuilt torque converter and transmission yet, but I will ensure that there is some play there to ensure I don't experience what was happening with the car when I got it. I am not sure yet, what the PO did to create this problem.

Good luck with your scenario.

Ford has 2 different sized hubs (or possibly more?) on the snout of the torque converter. Since you had a situation where there was improper end play on the converter, I suggest you check the hub diameter along with the end of the crankshaft. There are adapter rings which allow the use of the smaller hub converter on a crank with larger pilot bushing bore...it's possible someone installed a mismatched converter relative to your crankshaft pilot bushing bore.

I am pretty sure this is the original torque convertor for this car's application. There has been some discussion in the past whether the Code 63 or 65 was correct, but I can't be sure that this wasn't changed out at some time. I intend to check for proper fit/clearance/play when I go to bolt up the transmission in the near future. If anyone has anything to add based on these shots, let me know. Thanks


Attached Files
.jpg   vert 71 429cj torque convert.jpg (Size: 86.49 KB / Downloads: 31)
.jpg   vert 71 429cj torque convert2.jpg (Size: 81.77 KB / Downloads: 31)
.jpg   vert 71 429cj torque convert4.jpg (Size: 86.79 KB / Downloads: 30)
.jpg   vert 71 429cj torque convert3.jpg (Size: 81.37 KB / Downloads: 30)
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#12
basstrix;283738 Wrote:
Pastel Blue;283696 Wrote:On my recent BB rebuild, I had the rotating assembly completely balanced from the harmonic balancer back to and including the flexplate. The flexplate is new as when I got the car,, the starter was chewing the teeth on the flexplate. Both needed replacing during the rebuild. We had to add some weight to the flexplate to complete the overall balancing.

When I sent my C-6 in to be rebuilt, I was the informed that the front pump required changing due to the torque converter pushing back on the pump causing permanent damage to the pump... I learned there was no play for the torque converter to move back and forth slightly which caused it to create additional transmission damage.

There should be some play allowed for between the torque converter and the flexplate, but I do t think it will be such that you can push it back far enough so that the studis are clear and the torque converter can be rotated, that would seem like excess play to me...

I haven't bolted up my rebuilt engine, new flexplate, rebuilt torque converter and transmission yet, but I will ensure that there is some play there to ensure I don't experience what was happening with the car when I got it. I am not sure yet, what the PO did to create this problem.

Good luck with your scenario.

Ford has 2 different sized hubs (or possibly more?) on the snout of the torque converter. Since you had a situation where there was improper end play on the converter, I suggest you check the hub diameter along with the end of the crankshaft. There are adapter rings which allow the use of the smaller hub converter on a crank with larger pilot bushing bore...it's possible someone installed a mismatched converter relative to your crankshaft pilot bushing bore.

+1

Measure the snout of the torque converter and the pilot hole in the flex plate when you take it apart.

EDIT!!!!
Measure the snout of the torque converter and the pilot hole in your crankshaft.
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#13
The torque converter pilot registers in the crank, not the flexplate. Ford used two different sizes. 1.375 and 1.848. You need to measure the hole in the crank and use the appropriate converter.

The previous pump damage was probably the result of trying to mate the engine and transmission without the converter being fully seated on the input shaft splines. When the bell housing is against the mating surface of the block you should be able to move the converter back and forth between 1/8"-1/4" . If it is bound up there is something wrong and you will damage the pump if you tighten the bellhousing bolts.

73 conv. 460, D0VE large valve heads, Performer RPM manifold, Voodoo 227/233 cam, Holley 950 HP carb, C6 trans, 3.25 trak-loc.
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#14
TommyK;283746 Wrote:The torque converter pilot registers in the crank, not the flexplate. Ford used two different sizes. 1.375 and 1.848. You need to measure the hole in the crank and use the appropriate converter.

The previous pump damage was probably the result of trying to mate the engine and transmission without the converter being fully seated on the input shaft splines. When the bell housing is against the mating surface of the block you should be able to move the converter back and forth between 1/8"-1/4" . If it is bound up there is something wrong and you will damage the pump if you tighten the bellhousing bolts.

Thanks for correcting me!
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#15
TommyK;283746 Wrote:The torque converter pilot registers in the crank, not the flexplate. Ford used two different sizes. 1.375 and 1.848. You need to measure the hole in the crank and use the appropriate converter.

The previous pump damage was probably the result of trying to mate the engine and transmission without the converter being fully seated on the input shaft splines. When the bell housing is against the mating surface of the block you should be able to move the converter back and forth between 1/8"-1/4" . If it is bound up there is something wrong and you will damage the pump if you tighten the bellhousing bolts.

+1 ^^^ My transmission guy also stated the 1/4" play - back and forth, which would be common sense as well. if things are too tight in there, you know ahead of time and need to check for the problem before forcing the issue...

My crank and convertor line up properly for fitment, that was not the issue. Based on the shoddy rebuild of the engine previously, the use of sub standard bolts, what ever they could find to put things back together; more than likely it was a poor torque convertor to input shaft splines fitting.

I have no intention of rushing the install, it will be done correctly.
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