Spin off from other threads....

Not picking on any one brand of converter. I seen it countless times when pulling engine or trans out. On the face of the converter, you can see an outline that matches the large holes in the flex plate. This is not just a dust mark, its almost 'rusted' in. It dont wipe away. If the converter is not ballooning, how does it get there?

Joe Webb (RIP) and I talked about it 2 years ago and he said he has seen many times where converters will balloon when applied under high pressure. I dont know if he did this on some type of test stand or what, but I can see where it could happen.

What is the apply pressure of the TCC on a built trans with ~300 psi main line? The apply piston for TCC has how much surface area? 10 sq in? Assuming 100 psi of tcc apply pressure on 10 sq in, thats 1000psi of hit that is pretty harsh.. Can the cover sustain that with out deflecting?

It makes sense that there's all kinds of pressure on the cover, but wouldn't that apply equal pressure backwards into the transmission? Howcome we don't see damage to the pump gears? Or, do we?

It could be the converter pushing outward/forward, flexing the plate toward the engine, and allowing the centers to touch.

Maybe the covers on the newer converters are thinner, but I've been running my triple lok for 3-1/2 years now, and have none of the marking you state. I would say the flexplate is doing some goofy sh it, but highly doubt the converter is ballooning that much.

[quote=dmaxalliTech;1721612; On the face of the converter, you can see an outline that matches the large holes in the flex plate. This is not just a dust mark, its almost 'rusted' in. It dont wipe away. If the converter is not ballooning, how does it get there?

[/quote]


I am just speculating, but could that just be from the heat generated by the clutch when it engages?? Causing it "burn" the paint off, and leave the cover corroded.

I am with Turbotug on this one .