727 Debacle possibly converter?

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MoparMark91

MoparMark91

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How's it going guys well got a odd thing going on and looking for some advice or if someone has experienced this. So my dad and I went for a drive on about a month ago freeway,side streets, and mountain roads by a lake but at lower speeds. When coming back we came off the freeway I merged into the main road and noticed smoke coming out from underneath the car. Pulled over and the transmission is dumping fluid from the front of the bell housing at a decent rate, had to get it home and decided throw a quart from the trunk in it and finish getting home as we were only a few miles away. Got home dropped the tranny, and I had bought one rebuilt for cheap so was just going to do a quick swap since they were the same and rebuild the bad one. Well I put the torque converter on put the tranny back in the car everything all bolted together ready to run. I notice a drip starting to come from the front of the bell housing but I was figuring that maybe I spilled some out of the converter installing it? Well then I started the car and the leak is still maybe not as fast as flow of fluid but still coming out. I thought in the first one the front pump seal just went out or something but it's doing the same results on a different transmission? Nothing looked out of ordinary when I installed the converter? It's coming out and flinging out onto my headers. Guess I'll have to drop the tranny again and look but idk what else it could be?

71 dart 340 to 373 small block
Xe275hl cam
3.73 gears
727
3200 dynamic converter frank dynamic
9 1/2
I appreciate any help on this guys
 
Did you reuse the same converter? If so, like our fine feller up there suggests, the converter may be cracked.
 
RustyRatRod said:
Did you reuse the same converter? If so, like our fine feller up there suggests, the converter may be cracked.
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Yeah I'm leaning towards that too, but how exactly do u crack a torque converter? I didn't even hard launch it or anything. When I put it in new transmission it looked fine to me
 
MoparMark91 said:
Yeah I'm leaning towards that too, but how exactly do u crack a torque converter? I didn't even hard launch it or anything. When I put it in new transmission it looked fine to me
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Not being a smartass, but WHY does that even matter? Sometimes it just happens out of a fatigued spot in the metal, a bad weld or the like. It doesn't always have to be caused by an outside source. You might can get a small mirror in there and look around. Probably won't see a crack that way, but you can follow the path of fluid a little better and get a better idea of where it's coming from. If it was mine and I couldn't find any traces of fluid anywhere else but between the engine and transmission, that beeotch would already be on the ground.
 
It can happen from improper install it can happen from ballooning improper manufacturing to where it literally contacts flexplate bolts
 
Yeah I couldn't see anything but I'll drop it and see. It's brand new and have heard great things about the brand. Also upon inspection of the first transmission I saw my kickdown lever snapped off inside. Not sure if that would make more pressure on something either? I appreciate the input and help guys just bummed out cause I have to pull it again lol
 
The kick down lever is very important to regulate the pressure in the valve body. That's a good place to start troubleshooting. Check the kickdown linkage off the carb to start.
 
When checking fluid level, do you warm it up and put it in neutral? Just makin' sure you aren't over filling it.
Any weird wear on the front seal of the tranny that you pulled? My Frank Lupo 9.5 would not mate into that SCAT crank without honing the nub a couple hundredths.
 
The weld ring could have a crack or flaw. There's a way to check that in the 904/727 book by Tom Hand, who is on here occasionally. I always put in a new front seal if the converter is removed.
 
Look for something like this.
20200313_135102.jpg
20200313_135117.jpg
 
Converters can go bad in the blink of an eye. We were at the races & a fellow racer had put a new converter in his car a month prior, it had 10 to 15 test hits on it. He made 2 T & T passes & a weld developed a pin hole just as he made the turn out. It sprayed fluid all over the return road, the bottom of the car & everywhere else. He's lucky it happened when it did, not under a full pass.
 
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Once upon a time I had a cooler that was plugged and the trans puked fluid out the vent.
 
Thank you guys for the help, yeah I always make sure I idle for a bit in neutral to get the pump flowing, both transmissions have shift kits in them that I didn't do. My plan is to drop it then replace seal for peace of mind and inspect the torque converter. My dad and buddy both are betting on torque converter. It dripping when I first installed it. If I have to get new converter so be it I guess but I just want to diagnose and see what went wrong. I didn't have a cooler with it the first time and when I just put the new tranny in I put a cooler in line for peace of mind to keep it cool. If I do have to replace it I am thinking on getting a hughes 3000 stall, only change would be going to the 5/16 bolts as I'm using the beefy 7/16 bolts which I like. I have a old 340 torque converter but unsure of the stall or status of it. Probably better to get a new one again
 
I've had a conv crack on the hub like the pink one above. Mine wasn't centered on the crank and finally fatigued and cracked. Could not see the crack...put a rag and shop air to it and found it leaking that way. As others have noted, you won't nt always know why but just find the leak/crack and get it corrected.
 
Demonx2 said:
I've had a conv crack on the hub like the pink one above. Mine wasn't centered on the crank and finally fatigued and cracked. Could not see the crack...put a rag and shop air to it and found it leaking that way. As others have noted, you won't nt always know why but just find the leak/crack and get it corrected.
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Yeah I'm going to drop it tomorow and see what it looks like. I was thinking if I have to replace it then I'm going to go with a hughes 3000 stall. Only problem is on summit the hughes 24-30 doesn't show a ring gear attached to the converter? It comes with a ring gear right?
Hughes Performance 24-30 Hughes Performance Pro-Street 30 Series Torque Converters | Summit Racing
 
Behold! The hub of the converter was cracked all the way around the hub, pressure tested at well and it failed. Possibly from not having a inspection cover it looks like a rock kicked up and wedged itself at some point as well by looking at the grooves in it and bellhousing
 
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