Hot Rod Forum banner
1 - 6 of 6 Posts

·
Registered
Joined
·
1 Posts
Discussion Starter · #1 ·
Hey guys I'm having a really hard time with my transmission th350 non-lockout that I just put in my vett after all the mock-ups and work put forth. I fired this beast up and now I have no gears I sought that the guy I got it from lied to me that it was good. But any help with this matter would be great. before I attempt to take him this transmission back out of the car I'm hoping that it can be fixed before I have to do this
 

·
More for Less Racer
Joined
·
20,932 Posts
You'd have to pulll the pan to confirm it, but sounds like the link between the selector lever "rooster comb" and the manual valve in the valvebody either came loose or was overlooked during reassembly.
I'll admit to having missed it myself, on a TH-400.
Only possible if this is a fresh rebuild though.

Have you confirmed fluid is being pumped?
Engine running, crack a cooler line loose to see if fluid is moving.

What was your converter-to-flexplate gap at the bolt pads before it was pulled forward and bolted tight?
 

·
Registered
Joined
·
15 Posts
The GM, Turbo Hydromatic 350 is a simple transmission to diagnose, non lockup is even easier. Sounds like to me that the torque converter is misaligned with the front pump, you need to separate the engine and transmission, and when going back together, make sure that the flats on the converter align with the flats in the front pump of the transmission, it takes a little bit of finesse to make the mating, take your TIME.
 

·
True Hotrodder
Joined
·
1,955 Posts
The above mentions the rooster comb, fluid and convertor installation.
You should also check fluid level, shifter and shifter lever alignment. The seller said it was good but how long had it been out of use? A lot of times if a trans is pulled and just sits for an extended period, the valve body might need a good cleaning to make sure the valves in it will operate. If storage was for an extended time, then seals can also harden and internal pressure losses can cause the trans not to function although in this case with a loss of all gears, I do not think that is the issue.
 

·
Registered
Joined
·
78 Posts
613994

First always check your fluid level , from when it was last driven till now you probably know if you experienced fluid loss.
but always start with checking fluid. here is a picture of the S link it is connected to the linkage and the Manual valve.
this valve is the main valve that you operate when you move the linkage. Now I have always herd it referred to as a rooster "CONE" however mabe it was me now that I look at it , it does resemble a comb.
613995

The different serrations of the comb are in alignment with P Rnd21 ( some folks refer to it as prindle). So as you move the shifter thru the gears you can feel each individual gear position. The manual valve is moved by the shift linkage and aligned with each position via an "S" link (SELF EXPLANATORY) if certain internal parts are left loose or the manual valve breaks you might experience your shifter feeling as if it operates normally yet no gears enguage. this may very well be where you problem exists however if not its in the transmission and beyond your grasp. If its a fresh rebuild the company make it right. best of luck in your future endeavors !
 
1 - 6 of 6 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top