I have a really stupid question, only because I was stupid enough to screw up my first transmission installation; how did you bolt up the transmission to the block? When I did my first one, I put the converter on the flexplate, and then fed the tranny up to the block with the bolts... I ended up in a similar situation. First and reverse would sort of work, and it would rarely shift into any other gear. It's a dang miracle the truck even moved... I don't know if this is your first or not, but I thought I'd mention this. Good luck with it!
Take the governor and hold it with the gear at the top. Move the governor weights and make sure the valve inside the body is moving up and down with the weights. If its stuck knock the roll pin out and pull the gear off and pull the valve out and see why. Could be scored or debris jamming it.
Vacuum lines and down shift lever wont matter. If its got fluid, it should go into gear, just shift late based on Pressure not vacuum signal. I would think its the pump.... Did you put the Tq converter in right? 2 clicks or the pump will bind.... When you bolted the tranny to the engine, the converter should spin to align the bolts.... If it was on a bind against the Flex plate, then its not in all the way... You could also pull a tranny line off the cooler, start it, and see if any flows out, just don't run the tranny dry
The transmission should hold 11 to 12 quarts unless you have a high stall converter then it would be less. If you cut some vacuum hose two pieces about 3/8 to1/2" inch long and put them between your governor weights and the governor body your transmission should start out in 3rd gear. You will have to shift it manually this is a fast check to isolate the problem http://books.google.com/books?id=bu...#v=onepage&q=350 governor vacuum hose&f=false If you can't obtain third doing this I would suspect the governor bore; from your picture It looks like the governor (shaft is worn) how does the bore the governor goes in look? The bore can be reamed (special tool)and a brass bushing can be installed if the bore is worn.
I put the torque converter in correctly, filled with 1 qt. of fluid, pushed in and rotated until it was all the way seated. I can get it to shift into 2nd and 3rd, the shift is just way late. I'll pull the governor again tomorrow, check out the bore and go from there.
Go to the library and find you an automatic trans manual. Get out a pressure gauge and test the line pressure and governor pressure. You will learn a lot from those 2 tests. There are other ports you can test other things with, but these 2 are the ones you are interested in right now. Do the test as the book describes and see what the readings are compared to specs. I have an old Motors A/T manual that has all of that info in it and is a very important tool to have. You will need a pretty low pressure gauge to test gov. pressure with.
Do you know if the trans and torque convertor is any good, did it ever work right. I wonder if you have the wrong convertor like a high stall, full vacuum from manifold, make sure lever kick down feels like its doing some thing should have spring tension.
Also, check the bore the governor slides in. Sometimes the bore is worn. They make a bronze sleeve that you can install . A transmission shop can do this for you.
The late shift problem is text book classic symptom of a modulator related problem. Double check & with a gauge the vacuum source right at the modulator. Put a vacuum pump on the modulator and make sure it's working.
There are only two pressure taps on a 350 mainline pressure and 1/2 accumulator pressure; If you install a pressure gauge at idle in drive you should have 60 - 65 psi if it is higher than this you have a modulator issue (low vacuum, stuck valve etc.) when you rev the engine vacuum drops, pressure will rise to about 120 PSI. When the transmission shifts 1-2 and 2-3 you will notice about a 2-3 psi drop on the pressure gauge this happens pretty fast this is (control pressure cutback) and indicates your governor is working. There is no governor pressure tap on a 350 transmission. Do you have a red strip modulator on the transmission? If you do I would try a blue strip modulator; the blue strip modulator is for diesels this would require less vacuum to shift. Just my two cents.
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