I'm looking at a difference between older and newer 727s. The big block transmission from the '60s has one spring on the regulator valve. That's the one you can see when adjusting the line pressure screw. On the opposite side of the valve body is the regulator valve end plate that caps the orifice, the regulator valve line pressure plug, a sleeve and the regulator valve throttle pressure plug. For those of you following along at home, the exploded view is at http://www.imperialclub.com/Yr/1964/FSM/html/21-068.htm
One spring, and one only, is documented in every pre-1970 parts book and FSM I examined.
Now the problem: the ATSG manual for the newer 727s shows two springs -- the visible one and one more at the opposite end of the valve, between the throttle pressure plug and the valve itself.
My question is: What's the impact of having vs. not having that second spring in a '68 valve body? If this is a good thing, I'll put it in.
Please do not say, "If it's working fine without it, don't stress on it." I want to understand the reason it was okay in 1964 with one spring and okay in 1979 with two. Gosh, I'm demanding for someone who's petitioning the gurus...
Next, same thing with the shuttle valve. In the '60s, the valve sticks out the other end of the valve body and the e-clip goes around the valve proper to hold it in place. In the newer 727s, there is a spring guide, a spring, another spring guide and then the e-clip which goes around the spring guide that protrudes from the valve body. Why? Is this a good thing? What were the designers trying to accomplish when they made this change?
Whine, whine, whine. Who moved my cheese?!
Thanks,
David
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