<VV> Powerglide low gear problem

[Brent Covey]

Hi Mike-

>  It seems to have NO 1st gear. If you get it rolling it will go fine but
it will not start up from a stop. Reverse works fine. I suspect the low band
but I know NOTHING about a powerglide (or any other automatic). What is
involved in replacing the low band? Can it be done on the car?

If reverse works fine, the hydraulic system and engine driven front pump are
OK. If it continues working good and high gear works, the rear pump is OK.
Low band replacement if needcd requires the Powerglide (but not neccesarily
the diff or powertrain) to be out of the car.

This leaves us with something not getting low to engage. Low bands rarely,
if ever break and they take thousands of miles to wear out so if the problem
had a sudden onset, its likely not a broken or worn band. If a band did
break it would act like you're expereincing though.

I would expect the issue will be a valve body problem, perhaps the low/drive
shift valve sticking in the 'high gear' position.. Carefully remove the
valve body from the oil pan taking pains not to tear up the gaskets if you
dont have new ones, and carefully disassemble it one valve at a time to see
if theres an obvious sticky walve or debris in there. While its out, you can
pull the low band piston out, remove the spring that releases it, and return
the plunger to test with finger pressure if the strut seems to be engaging
the low band or not, you should be able to feel resistance when you press
the piston in against the band tightening on the drum. One other possibility
is the governor may be stuck in the 'upshift' position and siphoning off
pressure, this is the bell shaped devide ahead of the starter motor on the
back of the transaxle, the upper diff to trans bolt holds it in place with a
tab.

If you get no satisfaction, you probably should just try to find another
Powerglide (usually worth ~$50 or so)  if theres anyone locally with one
availible to you. Be sure to set up the running clearance correctly
(0.025-0.035") at the pinion shaft where the governor drive gear bottoms
against the trans output.

Its an interesting problem, I'll meditate on it, dont have my manuals handy
to see if theres any other possibilities but will check again later- hope
thats some help,
Brent Covey
Vancouver BC