So I had a cracked flex plate on my 62. I dropped the trans and swapped out the flex plate. Since the trans was out, i decided to dump out the old fluid as change the seals. I put it back together, filled it up to the mark, went through the gears while it was still up on the jack stands... everything was fine. Put it on the ground, took it for a cruise.. all was good. Today I have nothing. No reverse, drive, nada! What could be my problem. The trans was perfectly okay before... just needed to change the flex plate... Thanks, JC62
Perhaps the "S" link for the manual valve fell off ? That would be my first guess for such an abrupt "non op condition" after it was working fine. Check the modulator line and it's rubber connections. How much of a "seal replacement" did you do? Just the front pump seal, rear extension housing seal and possibly O ring, pan gasket, and accumulator seal? Pretty much just "external" seals, meaning you did't go into the transmission? I am Butch/56sedandelivery.
An perfectly operating old auto trans has a million things inside of it just waiting to go wrong when you even mess with it a little bit. Ask me how I know. For me the solution was a complete tear down, a kit from Fatsco, the shop manual and about the most difficult thing I've ever tried to do (twice because I didn't get it right the 1st time). If you study your manual, and get an idea how the trans works, you might be able to figure out what might have gone wrong. Doubt there's an easy fix, (although I could be wrong). Sucks dude. On the other hand, rebuilding an automatic transmission is one of the most satisfying things I've ever done, you might like it.
I changed the front pump seal and rear seal. Markyak... as a matter of fact I did. What could have happened?
I suppose you could have stirred up a bunch of debris and clogged the filter. Hard to imagine it wouldn't move at all though. Next ; Pull off a cooler line at the cooler, and put both ends in a bucket. Have a friend start it for about 3 seconds and then kill it. No fluid? Something must have happened to the pump. Out she comes!
ck fluid with engine off see where it is, then start it up if fluid goes down pump is working. what year trans? Some earlier 350s had an oil pump priming valve to keep oil in pump when you shut engine off. To ck that take a piece of heater hose and slip it over fill tube and blow into other end of hose with engine running and car in park or neutral then get in car and see if it will move in drive PARK or NEUTRAL for safety jack up rear of car .
It's kind of like life. You're alive..alive...alive then......... You're dead. This topic reminds me of my grandfathers 61 Pontiac with a 4 speed hydro. He never had a minutes problem with it. Drove it to the store to get milk, bread and a pack of smokes, cranked her up, no reverse and no drive. She gave it up right there in the parking lot.
You should check everything the guys have told you to check. An auto transmission works by a pump sending fluid at a very high pressure through various holes and channels. The fluid gets diverted into other holes and channels by little "gates" and devices to physically get different gears and things spinning and clutches engaged. If the fluid is not flowing for any reason (broken components, blockages), the rotating assembly won't work right or at all. There are a couple things you can try without pulling the trans if the above checks show no results. Luckily, you don't have to pull the tailpiece to take the governor out. This device diverts the fluid to certain places based on driveshaft speed, kind of like the mechanical advance on a distributer, or what keeps you up against the wall when you are on the Turkish Twist ride at a carnival. You'll want to check it to make sure it's intact and functioning The other thing might be to check the valve body, but it's not a good idea, too many small pieces. You could pull the pan and check the valve body for pressure from procedures in your repair manual. If there is no fluid pressure (easiest to check trans cooler lines) it's probably an internal problem I've heard of other th350's with the same symptoms having a completely thrashed front pump. The tangs can break. There's a good shot of the tangs, you can see how they could sheer if something might have been jammed when you started the engine after you put the trans back. But if this or another internal issue is somehow your problem, then it's pulling the tranny and tearing it down. You shouldn't be afraid of this. A rebuild kit will only be several hundred dollars (Fatsco), and you can do it yourself with some patience and hard work and a little help from a book, Harbor Freight tools and YouTube. A transmission shop will set you back $3k and you won't learn a thing. I'm far from a brain surgeon, I'm not a professional mechanic, I don't have serious deep technical knowledge like Gimpy, Squirrel or some of the other guys. To be blunt, if you saw me on the street you probably would hand me a dollar and tell me to get a job, but I did successfully do this job myself without any help or expensive tools. You can too. Hopefully it doesn't come to that and you can get it going. Good luck.
Did you empty the fluid from the converter and not add it back during reassembly? The first time (years ago) I did not seat the torque converter properly and not only had no gears, I cracked the pump. Dumb, but did the shift lever on the transmission slip?
In other words it worked good before and after you fixed it but quit after sitting. I'd put it on stands to see if it will turn the tires with no load.
I will re-phrase the question: Did you check the fluid with the engine running and warm, or off and cold? Or?
I had a similar problem on a TH350. It suddenly didn´t go in any gear . I found that the little plastic governor´s drive gear broke and the governor was stuck in between ports leaving the oilpassages open. You can see the gear in clunker´s pics above.
An update... I got the truck back up on jack stands. I drained the pan, luckily it does have a drain plug. First thing i checked was the governor. It was fine. Dropped the pan, checked the s clip. It was also okay. Installed new filter and gasket and reinstalled the pan. Loosened the converter and made sure it was on the pump properly. That's good. Filled it back up. Fired it up, put it in gear. Nothing at first. Gunned it out of frustration and it started working! Shifted good... let it sit for a few and again... Nothing. Gave it some gas, engaged again. The dipstick is showing the level of fluid is okay... maybe even a little high. Bottom line... it engages, but sometimes only if a get on the gas. Any ideas? Pump going bad? Thanks for all your input... JC62
That has crossed my mind, but it did read correct before. I'm starting up think there is air trapped in the system?
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