Hi guys, long time member here that has just started working on my Electra again. It has been running fine just going around the block or for a few miles. The trans does leak a small amount, but I checked the level and it was fine yesterday. I took it out and it would not shift from 1-2. Reverse is fine. I can drive it to the point it should kick into second...then nothing happens. I can't shift it manually from L1-L2 either. I previously bought a new filter, O ring and gasket and was planning on replacing once the weather warms up. Is there way to tell if it is just a stuck valve, or if it needs to be rebuilt completely? Thanks in advance. Shawn
Two things will cause that. One, if the vacuum modulator vacuum line falls of at the modulator, or the intake, it won't shift. The other thing that can cause it is if the kickdown connection is getting 12 volts constant. So first, check the vacuum line at both ends. Then pull the electrical connection off. It is most likely one of those two things.
Larry, thanks for the quick reply. I'm not sure where the vacuum lines are for the modulator or the intake. I'm assuming I will see them running into the trans? Sorry to be so clueless, and thanks again.
The vacuum modulator is on the passenger side of the car. It sticks out of the transmission towards the middle of the case. The vacuum line is a metal line with rubber hose on each end. It comes off the back of the intake manifold behind the carburetor towards the passenger side.
I had this exact issue and it was the vacuum line at the modulator. Go to the passenger side of the tranny. You will see a short section of hose and a very small steel line (tube). It runs up to the intake manifold and connects to a port behind the carb.
Zero vacuum at the modulator for whatever reason will make the transmission think that the engine is at WOT. It won't upshift at normal throttle, only at much higher RPM (4000 +)
Thank you all for your responses! I have a feeling that the hose is cracked or leaking. I will get under it later today. Off hand, does anyone know the hose diameter? I might just replace it while I'm there regardless.
Just to give an update, I checked both vacuum lines (the one at the manifold and the other at the modulator) and both are tight. It still isn’t shifting from 1st to 2nd, but I do have a leak as well. Dumb question, but if the trans cannot build enough pressure, would that prevent it from shifting up? Also, how can I tell if it needs to be rebuilt? I don’t have a burnt smell and I ran a qrt of Marvel thru it as well. Thanks in advance.
I disconnected it and cleaned it. It looked like the 2 blades on the connector were touching each other. So I opened the space a bit and reconnected the wire. Haven’t tried it yet.
I'm going to do that this week. Also, does anyone have the throttle linkage from the rod to the carburetor. Pic shows what I'm missing. Thanks
Just unplug the wire.... the missing piece thats not there is allows the switch to stay in passing gear mode.... In other words the WIRES are hot....
What you need to do is disconnect the connections at the transmission and leave them disconnected. Then drive the car. That missing rod makes that throttle switch non functional anyway. If there is constant 12 volts at the transmission kick down connection at the transmission (and there very well may be), it will NOT upshift. Pull the connections off and leave them hanging. Then drive the car. Your switch pitch won't work either the way it is.
Now while were at it your transmission is a ST400 not what you you called it........ It gets others confused with a standard TH400
Larry, The trans worked fine the way it is set up now until just recently. It has only been the past couple of weeks that it will not shift. I only have one wire connection at the trans. It has 2 blades in it. I will disconnect the one wire at the trans and try it.