Torque converter crack

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glhx

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Location
Middle Tennessee
76 transmission.
All original
Original converter

48009769243_467e20683a_z.jpg
This looks like a leak. Not bad that I know of.

The converter seal is new-

48009750093_883c02459f_z.jpg

this is cracked-looks like part of the seal in there

48009829897_e199e37db6_z.jpg

this is the other side -

48009749943_7a18695a31_z.jpg

just a closer shot

I’ve got to get this back in no matter what. I’m just trying to get a sense of what I’m looking at as far as what caused this and the time frame to total failure.
I don’t drive the car that much. But I need to understand the severity of the damage and what it could possibly lead to. Looks like it might be trashing the new seal as well. When I put the new seal in it was about ten years ago. I just don’t drive the car much. Seal probably has 800 miles on it. The torque converter didn’t look like that last time I saw it. Something must have worn out in the mean time.
I wasn’t even going to pull the converter but I figured why not.

The bushing might be shot and it’s sitting on the pump. How long does it have and can it be patched? Is what I want to know. If I can get another 3000 out of it, that would be nice

I’m not in a position right now to build a transmission and I’ve thought about 4 speeds anyway. Not bad luck....just an old car
 
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If that breakes off pump no pump wheels no go round and round. if it Jambs in there could do more damage. Just replace the seal and torque converter and press on.
 
If that breakes off pump no pump wheels no go round and round. if it Jambs in there could do more damage. Just replace the seal and torque converter and press on.
And you might need a pump. Have a transmission expert take a look.
 
MAybe.....but the bushing might be shot and the pump might be as well since the bushing might be gone.

A new converter would get trashed as fast as this one did if that’s the case.

It depends on how bad the bushing is. From the heat signature. It might have taken out the pump surface.

I don’t know and I don’t want to pull the pump without more guidance on what caused it.

The transmission might be shot due to this. I’m not sure.
If it is done....then I’ll ride it out until it blows sky high

If not.....I’ll fix what I can and try to save it
 
I have to fix it myself. I’m way over budget this year as it is. If it is the pump I can put one in....but if not worth it....

I posted that before I saw the reply

I’ll do what I can. Just looking at the possibility of the damage that caused it
 
Maybe @lkopaska can look at your pictures and give you a recommendation.
 
I sent him a pm

Hopefully he has an idea.

I’m betting the pump was taken out with it.
Next time.....bushing will be done as preventative maintenance

I replaced all the external seals. .....but not the pump seal or bushing

48010003957_b2d97dd1be_z.jpg

Front pump gasket and bushing that the torque converter rides on. Should have replaced this before hand.
 
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if this is a 904, thats not uncommon. I broke one in my sl/6 66 dart, when I took it to the dragstrip. It was a long time ago, but I think I just replaced the converter and maybe the seal, too.
 
what are the chances I wore through that bushing?
it wouldn't be a bad idea to replace the bushing. It's not that hard or even expensive to replace. You have to pull the pump with a slide hammer, drive out the old bushing, and drive the new one in square, and stake it. Refer to the FSM, it's all in there.
 
Look at the condition of the hub. The hub is done, and the bushing that supports it is also gone. I doubt that you wore through the bushing, although you won't know until you take the old one out. Remember, the converter hub must be like a journal on a crank, baby-*** smooth, and the surface it rides on (pump bushing) must also be baby-*** smooth. The seal will be shot too. You bought all the right parts, pump gasket, pump o-ring, bolt seals, pump bushing and the front seal. Replace all of those parts, or you'll be yanking the transmission out again, and have to do the job all over again. Oh, and while you're at it, have a close inspection on the two tangs on the inner pump gear. They could be FUBARED also.
On a side note: I never, in almost 30 years in the transmission business, ever saw a re-builder replace the converter without replacing all those parts you've purchased, especially the pump bushing. Even if the old bushing "looked" good.
DO IT RIGHT - ONCE!!
 
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I've never seen one that bad and not broken completely off. If you stick your finger down inside the converter, you'll see that the wall becomes a lot thinner further down. That's what causes them to crack. Lots of times tho, the converter can be a mess and the bushing unhurt. I had a guy install one and left it a gallon low while tuning and it ate 1/16" off the converter all the way around and didn't touch the bushing. At least look in there and see if both tangs are still present. But, I'd drop
out the front drums to check the clutches. Some old used ones are better than burnt ones.
 
That torque is dead. It just doesent know it.
Not a hope i would ever stick that back in.
I have 3 spare used ones in way better condition.
Im sure you could get your hands on a decent used transmission.
 
48010263622_28e6ef8f0b_z.jpg
Input shaft-bushing


48010263607_c372f9c04a_z.jpg
Input shaft 904 bushing -


48010176766_71dd8f9528.jpg
Input shaft 904 -

48010184603_699d95da32_z.jpg

Input shaft 904 is this cracked or is it made like that


I might have to put it back in for now and just not run the car. It’s not a big deal for me to pull the engine again. I have to be able to at least move the car
If I can find a good converter I’ll do that and put a new gasket behind that pump the first time.

I know the deal now and what it could cause. Yes.....that hub is shot. The crack alone will get worse and the parts will separate and grenade the transmission.

Looking at the bushing. It is shot. Despite the look of the hub being worn. It’s still not grooved. I’m hoping it’s didn’t do damage to the internal pump. If it did I’ll have to replace that.

What I’m wondering is why it got so hot.
That bushing is shot but the heat discoloration isn’t in the area of the bushing.

It’s in the area of the internal pump. What could cause that. It is locked into those tangs. Maybe there is play there and the tangs are worn down.....

What made this thing get so hot?

This is the original converter.
It probably didn’t break because I haven’t driven the car much at all before I had the engine back out and rechecked it. Except it wasn’t like this last time..
 
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Does any converter fit in there..
Like a 904 from a 360 without the weights or /6. There are a few for sale on here.

I’d rather not just put it back together before I repair it.
If any of you have one for a decent price I’m interested.
 
76 transmission.
All original
Original converter

View attachment 1715345282
This looks like a leak. Not bad that I know of.
The converter seal is new-

View attachment 1715345283
this is cracked-looks like part of the seal in there

View attachment 1715345284
this is the other side -

View attachment 1715345285
just a closer shot

I’ve got to get this back in no matter what. I’m just trying to get a sense of what I’m looking at as far as what caused this and the time frame to total failure.
I don’t drive the car that much. But I need to understand the severity of the damage and what it could possibly lead to. Looks like it might be trashing the new seal as well. When I put the new seal in it was about ten years ago. I just don’t drive the car much. Seal probably has 800 miles on it. The torque converter didn’t look like that last time I saw it. Something must have worn out in the mean time.
I wasn’t even going to pull the converter but I figured why not.

The bushing might be shot and it’s sitting on the pump. How long does it have and can it be patched? Is what I want to know. If I can get another 3000 out of it, that would be nice

I’m not in a position right now to build a transmission and I’ve thought about 4 speeds anyway. Not bad luck....just an old car
All original?
Looks like small snout convertor wobbled in a large convertor register too hard, was the flex plate trashed?
 
Auto zone will sell me one for $83

But it needs to be right based on what you just said.

Can you explain what you mean by this. I understand the small snout larger register. But what does that mean in terms of differences in years or engines.

Is a 904 a 904 and besides lock up....are they all the same
??
 
like I said before, my completely stock 225 sl/6 with about 300k miles on it cracked the converter neck. When I described the symptoms to my friend, Pat Blais ("TF Patty"), he knew exactly what had happened before he even laid eyes on it. He said it "happens all the time" with 904's.
 
That transmission would come down if it was mine. Where did all the metal go?
 
Pump could be ok , need to replace convertor, bushing, and front area gasket and o'ring. Factory 904 conv. Hubs thin down on inside just below notches and this causes a weak area in hub, this is one of the most common failures. Aftermarket hubs maintain thickness the full depth of hub and don't often fail.
Do you have a local trans shop near you?
If so pull pump and carry it in to them they should be able to replace bushing and seal and reassemble pump for you for a reasonable price including parts should be less than $50 .oo
DON'T try to reassemble it and run it or you will pay out big-time when it fails.
I have seen a broken hub lock up a good engine when it fails!!
Lon;
 
That bushing looks a little discolored but I can't condemn it from what I see. Stick the new converter in there before you put the seal in and see if it's loose. "Register" is the size of the hole in the back of the crank that the converter snout fits into. There was a smaller one back in the early sixties along with a coarser spline input shaft, but they didn't all change both areas at the same time. Yours is a simple match up (68-78). Any converter from that era will work as long as the four bolt holes in the front of it match your flexplate (which you should be checking for cracks). I would look around for a used converter for like $30. If it's a 360 converter, just grind off the weights.
 
I bought a new converter from autozone. It was $84

Was about to get seal kit from eBay until you said that a transmission shop might do it with parts for $20
The seal kit is $30 online.....so if they would actually do it for that. It would be nice.
I asked them a while back to rebuild a turbo 350 and they wanted like $2000. Was surprised

As far as putting a new bushing in there. What does it take to correctly do it myself? Why do they fail so badly when doing it yourself?
 
View attachment 1715345349
Input shaft-bushing

View attachment 1715345350
Input shaft 904 bushing -

View attachment 1715345351Input shaft 904 -

View attachment 1715345352

Input shaft 904 is this cracked or is it made like that

I might have to put it back in for now and just not run the car. It’s not a big deal for me to pull the engine again. I have to be able to at least move the car
If I can find a good converter I’ll do that and put a new gasket behind that pump the first time.

I know the deal now and what it could cause. Yes.....that hub is shot. The crack alone will get worse and the parts will separate and grenade the transmission.

Looking at the bushing. It is shot. Despite the look of the hub being worn. It’s still not grooved. I’m hoping it’s didn’t do damage to the internal pump. If it did I’ll have to replace that.

What I’m wondering is why it got so hot.
That bushing is shot but the heat discoloration isn’t in the area of the bushing.

It’s in the area of the internal pump. What could cause that. It is locked into those tangs. Maybe there is play there and the tangs are worn down.....

What made this thing get so hot?

This is the original converter.
It probably didn’t break because I haven’t driven the car much at all before I had the engine back out and rechecked it. Except it wasn’t like this last time..

Are you going to use that scored up transmission input shaft? I cannot believe these guys are advising you ro reuse that. No way in heck would I do it. That transmission would be coming slam apart. I can see no amount of advice is going to get you to actually repair it. Especially since you bought an 84 dollar torque converter. Some things are worth stepping up "a little bit" on.

I wish you luck.
 
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Nobody is even going to sneeze on a transmission for $20. If both tangs are still in there, then put a seal in it and a quart of trans fluid in the converter and put it together.
 
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