700R4 Won't Engage/Move

Working on my 48 Chevy 6.5 project, and am trying to use a (supposedly good) used 700R4.

In trying to test the trans, I get no engagement when I put it in gear-forward or reverse. I only hear a slight whine from the trans.

It seems the pump isn't pumping-I checked the oil cooler lines and no flow. I serviced the trans before I installed it in the car, it looked good, with no metal and no evidence of burning. I also drained the TC as much as I could.

The trans did sit for quite a while before I bought it-could something be stuck? I pulled the pan again tonight, with nothing obviously wrong, It seems to have plenty of fluid, although it didn't take much to show on the dipstick, about 5 qts, especially since I drained the TC.

Short of pulling the trans, is there something else I can check first?

Thanks. Joe.

If you only added 5 qts, you're a LOT short. It won't engage with fluid that low. Get the air out and the fluid in before you condemn the tranny.

With the engine running (rig on flat ground) trans in N check the stick.

Add fluid until the level is in the middle of the normal range.

Cycle the selector through all ranges R N D 3 2 1 Slowly to allow systems to purge.

When checking level, do so in N (Use park brake or chock wheels)

5 Quarts is nowhere near a full fill, especially if you dumped the converter.

Keep adding and cycling the shifter until the level is solid in the normal range.

My bet is it will work fine.

Be sure to adjust the TV cable correctly before driving.

Good luck

Thanks, it's worth a shot.

It just seems like it's not even beginning to pull any fluid, but I don't think I've let it run in N for any decent amount of time.

Should I open one of the cooler lines to help it 'purge'?

Joe.

No purging needed, as any air will escape easily.

The cooler return line is a lube line and and air purges right out.

The normal fill on a 700R is ABOUT 10 qts when dry.

The 5 qts you poured in likely all went into the converter.

Even with the fluid just below the stick the tranny will not like it.


Once on the stick when running, things should start happening.

You also have a capacity in the cooler/lines too, not much butttttt some.

Still can't get it to pump any fluid.

I put at least 9 qts in - it's well above the "hot" level on the dipstick, but it doesn't draw down. No flow out of the oil cooler ports.

I guess it's looking like a bad pump. Any other ideas?

Seems like the TC is turning the pump - I hear a slight whine and the driveshaft wll turn slowly due to centrifugal force, but no actual 'driven' rotation. I changed the filter before I installed it.

Thanks again.

Was the Torque Converter set in the pump before you tighten the bellhousing bolts? If not, you may have cracked the pump.

As HH said, You may have cracked the pump. Did you draw the trans into the engine using the mounting bolts? did you hear a pop when you did this? This is a common mistake, and should not be done. The trans should be pushed as far into the engine as possible with no more than 3/8 of an inch between them. you can then sequentially tighten the bolts. You may want to drop the pan to see if the filter fell off. when you changed the filter, the o ring on the old filter may have pulled off the pickup tube, and stayed in the boss. Also, make sure the TV cable is adjusted properly before you move the vehicle. this is very important as you can ruin the trans by not doing this.

Re reading this thread.

You had the converter out of the tranny and dumped it.

You then stuffed it back in.

If you did not spin it by hand while holding in on the converter and have it drop all the way in it is very easy to Eff things up.

There are several things that must engage when the converter is installed.

The pump drive tangs
The input shaft
The stator support.

With the flex plate bolts out, the converter should slide back into the bell housing easily about 1/2 inch away from the flex plate.


If the converter was not installed correctly, the pump/stator assembly is likely damaged.

You are going to need to rip it out and inspect the pump.

The converter hub may also be damaged as well.

Quicky check
Remove the flex plate bolts.
If you can wiggle the converter and have it slide back away from the flex plate
THIS IS GOOD

Next do as dozer says

Check the area in the trans body that the suction tube from the filter plugs in and be sure the old seal unit is not crammed up in there.
Having things messed up here will cause the pump to suck air.

Be sure the pickup tube is in good order.

If both of these things seem OK
Then it's time to rip deeper.

Hey Joe. I really have no faith in "good used" 700R4's. It was removed from a vehicle for a reason, and you may dump more money into this thing than it's worth. I have made that mistake, believe me. Seeing as you are restoring your old truck, you may want to go with a good performance trans that has all the heavy duty goodies. Not to plug them, but I went with a Monster Transmissions super duty 700R4 in my M1031/K30. The truck is a heavy beast, and weighs in at about 7000 pounds with all the crap I have bolted to it. I've had it in the truck for a little more than two years, and it still shifts like it did the day I installed it. Just a suggestion.

Thanks for all the thoughts, everybody, and my apologies for not updating this sooner...

As some of you suggested, evidently I made a rookie mistake and damaged the pump while installing the trans. After ruling everything easy/obvious, I went ahead and pulled the trans.

Could definitely see the damage to the pump. Boy, they are rather fragile - the TC seem to be engaged and not out of alignment when I tightened the trans. Oh, well.

I decided to go ahead and have the whole thing gone through - I'm using a local rebuilder that supposedly sets up higher performance diesel automatics and claims to have a lot of 700R4 experience. We'll see...

Thanks again for all the suggestions.