Turbo350/350 lost power.

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Karnawgie

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Not sure what other forum or group to post in, as I'm sure there's lots of knowledgeable folk in here.

Got my 350 back In my 75 lemans after putting in freeze plugs and doing some other stuff. My first test drive up the road was great, shifted through all 3 gears and was smooth.

I put the car in neutral to rev it and hear the engine, dropped back in drive and and lost all power. Second, nothing. Had someone help me top of the trans fluid, nothing. It has park, and it does shift into neutral etc but no movement.

I'm very unknowledgable as far as transmissions go, I'm learning. I'm thinking my torque convertor lost too much fluid when I pulled the engine, or maybe it became unseated? I don't know. Gonna dive In soon and learn, what do you guys think?
 
alright guys, I got the car off the ground and unbolted my torque convertor and spun it. It seated another quarter inch and made a noise, I guess this means my trans was not running the pump and I've toasted it. I also suppose i messed up not pulling and refilling my torque convertor. Now what?

What have I most likely hurt here? Can I get away with just replacing a few parts? Guess I'm looking for a new trans?
 
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Not too clear how you can completely bolt a torque converter to the ring gear and have the transmission completely bolted to the engine yet still not have the torque converter fully seated.
Did you check the fluid level before going for the drive?
How much fluid did you add?
You added the fluid with the engine running and fully warmed up?
The vacuum modulator line is connected?
Did you have to adjust the kickdown cable when you installed the engine?
 
melsg5 said:
Not too clear how you can completely bolt a torque converter to the ring gear and have the transmission completely bolted to the engine yet still not have the torque converter fully seated.
Did you check the fluid level before going for the drive?
How much fluid did you add?
You added the fluid with the engine running and fully warmed up?
The vacuum modulator line is connected?
Did you have to adjust the kickdown cable when you installed the engine?
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I don't remember every detail of bolting everything up but everything did bolt up. After tightening bellhousing bolts, there was maybe 3/16th inch gap between my flexplate and torque conveter. I bolted it up and think the torque convertor slid forwards that amount.

After that I added about 4 quarts cold. The kickdown cable had cracked at the transmission, and was leaking so I replaced it. I buttoned more things up, and added another quart before my drive. Then let the engine warm up, and drove up the road and back. Was fine.

The modulator is hooked up, and shifted through all 3 gears fine on both of my little drives.

The kickdown cable is also something new to me, didn't adjust it. As a matter of fact it was still loose on my pedal and wasn't functioning on my test drives. Was just feeling everything out and didn't think it would hurt. It was connected to the arm in the trans and seated though.

This morning I started it up and put it in gear cold, nothing,

Got it in the air this morning and this is where I've updated things.

Seating the torque convertor that extra 3/16" and re-bolting the flex plate, it seemed to want to pull the torque convertor forward, I left the bolts all the way loose, so it is seated as much as possible and started it on jack stands and still no power. All gears feel like neutral and driveshaft is spinning ever so slightly.
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So you never checked the fluid level with the engine running, fully warmed up and moving the shifter through all gears and then back to park?
Did you check if moving the shifter actually moves the lever on the transmission case?
 
melsg5 said:
So you never checked the fluid level with the engine running, fully warmed up and moving the shifter through all gears and then back to park?
Did you check if moving the shifter actually moves the lever on the transmission case?
Click to expand...
I did check my fluid after topping it off in the parking lot, it was over full, to the pointy notch in the dip stick. That's where I've always ran my level cold in this car and my 700r4 truck. I guess there's a small chance it's low on fluid but I've put over 5 quarts in it no doubt. Right now, cold, it is an inch above that notch.

The shifter cable and arm does operate on the transmission. It can see it go from park all the way down to low. Park holds the car.

I suppose letting the car warm up and checking, or just adding another quart or two would be in order here.

Id think if the torque convertor drank a quart after starting my test drive, and then I added a quart after it lost power, it'd work.
 
I just bolted up my tc with 2 washers in between the convertor and the flexplate to make sure its as far back as possible. Let it idle for 5-10 minutes and my coolant temp reached 180. The trans dipstick reads 3-4" over the full hot mark, about the same cold. Its above the pointy notch in the stick.
 
Karnawgie said:
I just bolted up my tc with 2 washers in between the convertor and the flexplate to make sure its as far back as possible. Let it idle for 5-10 minutes and my coolant temp reached 180. The trans dipstick reads 3-4" over the full hot mark, about the same cold. Its above the pointy notch in the stick.
Click to expand...
If it 3" to 4" above the hot mark with the engine running it's WAY overfilled and the fluid will aerate into a foam causing transmission failure.
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melsg5 said:
If it 3" to 4" above the hot mark with the engine running it's WAY overfilled and the fluid will aerate into a foam causing transmission failure.
Click to expand...
I was thinking the dipstick reading way too much means the pump isn't working or circulating any fluid causing it to be a pretty static amount. I will get a little hand pump and remove fluid.

What exactly would aerating fluid do to a trans? What kind of failures would occur?
 
Karnawgie said:
I was thinking the dipstick reading way too much means the pump isn't working or circulating any fluid causing it to be a pretty static amount. I will get a little hand pump and remove fluid.

What exactly would aerating fluid do to a trans? What kind of failures would occur?
Click to expand...
Aerated fluid will exert very little pressure on clutch plates and bands because it's full of air. Did the fluid look foamy when checking with a running engine?
 
I pulled about 2-3 quarts from the trans, cold level was a little above the hot full mark and after a few minutes of running it did not change.
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So still overfilled. The washers shouldn't have been needed. Any chance the pickup tube in the pan fell out of the case?
 
I can pull some more fluid out tomorrow and try again. Shouldn't the dipstick level drop once its warmed up? its staying the same. The dipstick tube is seated in the trans, can triple check that tomorrow too.
 
Karnawgie said:
I can pull some more fluid out tomorrow and try again. Shouldn't the dipstick level drop once its warmed up? its staying the same. The dipstick tube is seated in the trans, can triple check that tomorrow too.
Click to expand...
Fluids expand as they warm up, the level goes up. Not the dipstick tube. The pickup is inside the transmission pan with a filter attached to it.
 
Id assume the internals/pickup of the trans was fine, I've never dropped the pan. I guess that could have made some sense with a complete loss of power but no clunk or noise.

This morning I added a couple quarts back and removed my lower line from trans to radiator, presumably my feed/pump line. Ran it for 30 seconds to a hose to a clear jug. Not a drop from the line or from the radiator.

If the pump died because of improper torque convertor install, and I sheared my ears on the test drive, damage was done. If the pickup tube fell out and I lost power, after all this idling and testing i've done, i believe damage has probably been done.
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