TF727 issues

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prorac1

prorac1

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strange issue with our rebuilt TF727.

At first it engaged and drove up and down the driveway perfect.

Today I was making some carb adjustments, and backed it outside to mess with it.

It’s running great.

But.

When I went to pull it back in, I put it in gear, gave it some gas, and that’s where it gets bad.

It acted like it went into neutral for a split second. Reved up about 400 rpm and than bangs into gear.

If your already rolling, and give it gas it’s fine. But from a dead stop it flashes than bangs into gear.

Does this in all gear selector positions.

Any help is appreciated. Thanks. Eric
 
I will also add.

Stock torque converter

Checked the fluid, it’s showing just under a pint over filled

Lokar kickdown cable (but I don’t think kickdown adjustment has anything to do with this)

Thanks. Eric
 
Sounds like low fluid. Did you check it warm, idling in neutral? (block the wheels or have a helper)
 
It appears that people refer to this as “gear drop out at idle”……

But I have yet to find anybody that has figured out why in google land. Lol.

Any help is greatly appreciated.

Thanks. Eric
 
Over full causes air in the fluid. even a pint.
Sound like a kick down cable adjustment to me.
I may be wrong but that is where I would start.
 
Jadaharabi said:
Over full causes air in the fluid. even a pint.
Sound like a kick down cable adjustment to me.
I may be wrong but that is where I would start.
Click to expand...

Thanks.

Planing on draining a quart out tomorrow and readjusting the kickdown using the full throttle method.

It also has delayed shifts into second. Doesn’t shift at part throttle till about 3000 rpm.

But I’m not convinced that the two problems are connected.

Thanks. Eric
 
MoparLeo said:
Home rebuilt ?
Click to expand...

Yes. By me and a buddy of mine.

It worked great until I removed and replaced the carb.

That and I noticed it shifts into second at around 3000 rpm at part throttle.

We’re going to drop the fluid level, and readjust the TV cable.
 
But I don’t see how TV cable adjustment would make it seemingly drop out of gear at idle, than bang back into gear when you give it gas.

But we’re going to readjust it today anyways and see what happens.
 
Once you change the carb or make adjustments to the carb you must adjust the kd lever all over again . Like previously stated : disconnect the kd cable/lever and see if any changes . Remove 1pint of fluid and see if that helps . Check your shift linkage adjustment . the adjustment MUST be dead on or it won't function correctly . Ask me how I know !
 
Looks like you have another thread back in November for binding in the kickdown lever movement. Whatever happened with that, if it's the same car/transmission.
Wondering if that binding finally resulted in damage to the kickdown circuit at the valvebody, and now it's leaking pressure.
 
Eric, Check the Valve Body bolts. All should be at 100 inch pounds. If the valve body is loose you will have all kinds of funky symptoms. Wouldn't be the first time I've seen it. Strange though that everything worked fine until you changed the carb.
 
It takes over a quart to overfill a trans. Are you checking both sides of the stick; idling in neutral?
 
383Scampman said:
Once you change the carb or make adjustments to the carb you must adjust the kd lever all over again . Like previously stated : disconnect the kd cable/lever and see if any changes . Remove 1pint of fluid and see if that helps . Check your shift linkage adjustment . the adjustment MUST be dead on or it won't function correctly . Ask me how I know !
Click to expand...

Thank you very much for the reply. We didn’t change the carburetor. I removed it to make adjustments to it that couldn’t be done with the carburetor mounted.

We disconnected the kickdown. It made no difference to the problem.

We removed a quart of fluid from the transmission. No change.

I’m not concerned with it being too low on fluid. We have a 2 quart extra capacity Pan and extended pick up.

We removed the shift cable from the shifter and manually pull the cable into gear and it still does it. Therefore eliminating shifter adjustment.

I am truly beating my head against a wall at this point. LOL. Thanks. Eric
 
Bobzilla said:
Looks like you have another thread back in November for binding in the kickdown lever movement. Whatever happened with that, if it's the same car/transmission.
Wondering if that binding finally resulted in damage to the kickdown circuit at the valvebody, and now it's leaking pressure.
Click to expand...

That ended up being the bracket down on the transmission for the kickdown. We had too much angle on the table. We designed a new bracket to fit inside the tight transmission tunnel and now have free movement.

The transmission worked perfectly two weeks ago. We double checked everything that we changed in that time. It started doing this out of the blue. For all I know it could be an internal seal issue. It’s looking like that is our next area to check.

Thanks. Eric.
 
CudaFactHackJob said:
It takes over a quart to overfill a trans. Are you checking both sides of the stick; idling in neutral?
Click to expand...

Yes. Checking both sides of the stick, idling, in neutral. It is entirely possible that the dipstick could be out to lunch. I haven’t completely eliminated that as a possibility either. Thanks. Eric
 
Last edited:
We also readjusted the kickdown for full operation at full throttle. In the past we have also verified that the swing on the carburetor and The swing on the transmission and are the same distance.
 
Last edited:
KickDown said:
Eric, Check the Valve Body bolts. All should be at 100 inch pounds. If the valve body is loose you will have all kinds of funky symptoms. Wouldn't be the first time I've seen it. Strange though that everything worked fine until you changed the carb.
Click to expand...

Going inside the pan is going to be our next step if this doesn’t get resolved. Thanks. Eric
 
But……I installed a 4.5 pv today and readjusted the idle mixture screws and the engine is running amazingly well. Lol. ……we have that going for us. Lol
 
Seems it started when you removed the carb and tp cable. .....
Hate to say it, like others, but I'd put my money on the tp cable.


Jeff
 
MrJLR said:
Seems it started when you removed the carb and tp cable. .....
Hate to say it, like others, but I'd put my money on the tp cable.


Jeff
Click to expand...

I wish I could agree with you. LOL. But we’ve ran it disconnected, and readjusted it five times. LOL. No difference. To me it acts like a low pressure issue. Then once you bring the RPMs up a couple hundred rpm’s pressure increases and bangs back into gear.
 
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