TH400 no gear engagement
Thread Starter
Joined: Dec 2001
Posts: 12,829
Likes: 30
From: Central Indiana Honors: 4th grade spelling bee contestant
TH400 no gear engagement Trying to get my build moving under its own power (thread link in sig), but the '89 TH400 I have in the car will not engage into any gears.
Here is what I have checked. Am I missing anything?
1) Fluid level is good.
2) Pump works-fluid at trans cooler and tailshaft.
3) Linkage works as it should.
4) Internal linkage works and appears to be hooked up.
5) Found detent solenoid disconnected inside trans, so corrected that.
6) Lokar unit for activating detent solenoid hooked up correctly, and plugged into vertical terminal.
7) Vacuum line from intake to modulator valve is hooked up.
Here is what I have yet to check:
1) Fluid in modulator valve hose? Valve is fairly new, but I won't rule it out as being faulty either.
2) Pushrod connected to shift valve at modulator?
3) Governor gear stripped?
Am I on the right path? Any advice will be greatly appreciated.
Here is what I have checked. Am I missing anything?
1) Fluid level is good.
2) Pump works-fluid at trans cooler and tailshaft.
3) Linkage works as it should.
4) Internal linkage works and appears to be hooked up.
5) Found detent solenoid disconnected inside trans, so corrected that.
6) Lokar unit for activating detent solenoid hooked up correctly, and plugged into vertical terminal.
7) Vacuum line from intake to modulator valve is hooked up.
Here is what I have yet to check:
1) Fluid in modulator valve hose? Valve is fairly new, but I won't rule it out as being faulty either.
2) Pushrod connected to shift valve at modulator?
3) Governor gear stripped?
Am I on the right path? Any advice will be greatly appreciated.
Thread Starter
Joined: Dec 2001
Posts: 12,829
Likes: 30
From: Central Indiana Honors: 4th grade spelling bee contestant
Vacuum Modulator is good. No fluid in the spout of it or in the vacuum line. Vacuum line is free of obstructions, and has good vacuum when the car is running. I removed the modulator and checked the piston and o-ring. Modulator is seated well on the pushrod. Double-checked the internal linkage again. Put the pan back on, and will be putting the trans fluid back in. This time I'm going to let the car run and get good and hot. I'm thinking I have yet to get the transmission hot enough to get all the necessary fluid into it so it will work properly. If this doesn't do the trick, then I'm back to square one.
Thread Starter
Joined: Dec 2001
Posts: 12,829
Likes: 30
From: Central Indiana Honors: 4th grade spelling bee contestant
Let it get good and warm, but the fluid level never budged. From my research, that leads me to believe the pump is bad. Any suggestions or a better outcome?
Thread Starter
Joined: Dec 2001
Posts: 12,829
Likes: 30
From: Central Indiana Honors: 4th grade spelling bee contestant
Put all fours up on jackstands tonight, and found my issue. I can turn the rear tires (which in turn turns the driveshaft) in either direction in every gear except "Park". That would be the gear I'm least concerned about at this point.
I guess buying used on Craigslist came back to haunt me. I've had the trans for over 6 years, and I know it's an '89 out of a van.
Bit the bullet and ordered a more appropriately set up TH400 and converter from a reputable company.
I guess buying used on Craigslist came back to haunt me. I've had the trans for over 6 years, and I know it's an '89 out of a van.
Bit the bullet and ordered a more appropriately set up TH400 and converter from a reputable company.
Thread Starter
Joined: Dec 2001
Posts: 12,829
Likes: 30
From: Central Indiana Honors: 4th grade spelling bee contestant
