HELP 2 minutes to 12o' clock - Disaster averted - Advice/Help needed

64nailhead

Goat Herder
Supporting Member
Dec 1, 2014
4,965
113
Upstate NY
The converter was bound in the pump. It wasn’t floating. That’s the cause of your engine damage. And there’s probably metal in the trans too.
This^^^^^is spot on.

Wrong flexplate, wrong converter spacing or something. The horizontal marks on the converter hub tell all of the story. With those marks, it's a guarantee that the thrust bearing was gonna get destroyed.

This was doomed when it was put together.
 
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ELCAM

G-Body Guru
Jun 19, 2021
703
93
Looks like the torque converter was not installed correctly. When it is proper you have to pull it to the flex plate about a 1/2 inch, maybe more when putting the bolts in. I would at least pull the pump and see what damage has been done inside the pump and see how much junk was circulated through the transmission.

You're going to need a new torque converter too. The galling on the pump drive is not cool and it also looks like it got very hot.

Make sure the flex plate is flat and look for cracks, it likely got bent, might be best to replace it too. It will cause cracks if it is flexed too far and too often.
 
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FluoFerret

Greasemonkey
Thread starter
Apr 2, 2018
184
43
Luxembourg
The converter was bound in the pump. It wasn’t floating. That’s the cause of your engine damage. And there’s probably metal in the trans too.

This^^^^^is spot on.

Wrong flexplate, wrong converter spacing or something. The horizontal marks on the converter hub tell all of the story. With those marks, it's a guarantee that the thrust bearing was gonna get destroyed.

This was doomed when it was put together.

Looks like the torque converter was not installed correctly. When it is proper you have to pull it to the flex plate about a 1/2 inch, maybe more when putting the bolts in. I would at least pull the pump and see what damage has been done inside the pump and see how much junk was circulated through the transmission.

You're going to need a new torque converter too. The galling on the pump drive is not cool and it also looks like it got very hot.

Make sure the flex plate is flat and look for cracks, it likely got bent, might be best to replace it too. It will cause cracks if it is flexed too far and too often.


Thank you all so much for this invaluable information. (y)

I will take a closer look at the pump drive. if I am lucky enough, the damage is not worked too deep into the metal, and the risk of metal shavings is low, reduced to "just metal dust" like brake dust on the rims. there are good chances, since the engine/transmission never took any beating during all these years. always took it slow and easy on the accelerator.

If I find damage in the pump, I think I will just tear down and rebuild the transmission and replace all the clutchbands, just to be sure.
 

64nailhead

Goat Herder
Supporting Member
Dec 1, 2014
4,965
113
Upstate NY
Thank you all so much for this invaluable information. (y)

I will take a closer look at the pump drive. if I am lucky enough, the damage is not worked too deep into the metal, and the risk of metal shavings is low, reduced to "just metal dust" like brake dust on the rims. there are good chances, since the engine/transmission never took any beating during all these years. always took it slow and easy on the accelerator.

If I find damage in the pump, I think I will just tear down and rebuild the transmission and replace all the clutchbands, just to be sure.
Dropping the trans pan will tell you what you need to do. Any glitter and you need a rebuild.
 
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FluoFerret

Greasemonkey
Thread starter
Apr 2, 2018
184
43
Luxembourg
Dropping the trans pan will tell you what you need to do. Any glitter and you need a rebuild.

That's where I personnally screwed up, probably 4 years ago:
Oil pan gasket leaked, and replaced it by a Felpro. When I had the pan off, i found some greyish sludge that I considered to be regular wear of the clutches. I can't remember though if there was some bigger metallic glitter in it. just cleaned the oilpan out witth breakfluid, dried it and reinstalled with a new gasket and new transmission fluid.
But if the transmission and engine suffered because of the terribly botched converter installation, chances are now high that this greyish sludge may be a result of excessive wear of the clutches :cautious: i dread now taking off the oilpan to check...
 

Supercharged111

Comic Book Super Hero
Oct 25, 2019
3,711
113
Colorado Springs, CO
That's where I personnally screwed up, probably 4 years ago:
Oil pan gasket leaked, and replaced it by a Felpro. When I had the pan off, i found some greyish sludge that I considered to be regular wear of the clutches. I can't remember though if there was some bigger metallic glitter in it. just cleaned the oilpan out witth breakfluid, dried it and reinstalled with a new gasket and new transmission fluid.
But if the transmission and engine suffered because of the terribly botched converter installation, chances are now high that this greyish sludge may be a result of excessive wear of the clutches :cautious: i dread now taking off the oilpan to check...

Don't.
 

CopperNick

Royal Smart Person
Supporting Member
Feb 20, 2018
2,223
113
Canada
Best way, unfortunately, to determine the extent of any damage to the t-mission is to drop the pan and pull the pickup/filter. Anything resident is likely to be sitting on the floor of the pan or got trapped by the magnet, hopefully. if all you find is a thin layer of gray-ish sediment once you dump the pan, you might have got off lightly. Still, the final vote on that would be to pull the front pump and open it to see what's to be seen.

At the very least your motor needs to be completely torn down. Why? Because the material ground away from that thrust bearing had to go somewhere, and the block's oil passages are a good hiding place for evil. Even though the crank seems useable, the excessive heat it was exposed to is not a good thing, same/same with the rods. Subject to other considerations, your best option might be a long block replacement from somewhere such as Summit Racing or?? If you elect to have this mill rehabbed then be prepared for a long butcher's bill of machine shop costs as to do it right they will have to first take it apart, and then hot tank it, and then inspect and measure and mike everything,

Further, and beyond all this, you will have to get into that engine bay and cut away all that mickey mouse motor mount BS that supported your old motor. The factory uses bolts and biscuits on its mounts for a reason and trying to cut costs and time by welding them instead of taking the time to correctly locate and secure them properly; well, even as little as a 1/16th of an inch of misalignment during the welding process and the motor becomes "cocked" or mis-aligned. Gotta wonder at this point if what that shop did wasn't just to assemble the complete mounts to the engine, drop the whole business in the car and weld it in place just as it landed without taking a tape to it.

JUst me here, thinking aloud.



Nick
 
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FluoFerret

Greasemonkey
Thread starter
Apr 2, 2018
184
43
Luxembourg
Best way, unfortunately, to determine the extent of any damage to the t-mission is to drop the pan and pull the pickup/filter. Anything resident is likely to be sitting on the floor of the pan or got trapped by the magnet, hopefully. if all you find is a thin layer of gray-ish sediment once you dump the pan, you might have got off lightly. Still, the final vote on that would be to pull the front pump and open it to see what's to be seen.

Just had the pan down and found a few on the plug-magnet. Guess its rebuilding time, since i don't want to gamble on getting by only to have my transmission fail next summer over this ^^

At the very least your motor needs to be completely torn down. Why? Because the material ground away from that thrust bearing had to go somewhere, and the block's oil passages are a good hiding place for evil. Even though the crank seems useable, the excessive heat it was exposed to is not a good thing, same/same with the rods. Subject to other considerations, your best option might be a long block replacement from somewhere such as Summit Racing or?? If you elect to have this mill rehabbed then be prepared for a long butcher's bill of machine shop costs as to do it right they will have to first take it apart, and then hot tank it, and then inspect and measure and mike everything,

Further, and beyond all this, you will have to get into that engine bay and cut away all that mickey mouse motor mount BS that supported your old motor. The factory uses bolts and biscuits on its mounts for a reason and trying to cut costs and time by welding them instead of taking the time to correctly locate and secure them properly; well, even as little as a 1/16th of an inch of misalignment during the welding process and the motor becomes "cocked" or mis-aligned. Gotta wonder at this point if what that shop did wasn't just to assemble the complete mounts to the engine, drop the whole business in the car and weld it in place just as it landed without taking a tape to it.

JUst me here, thinking aloud.
The engine is already disassembled to the block and sent to a well reputated shop to check for cracks, damages, refurbishing the surfaces, and a deep cleaning. the crankshaft is for the scrap yard anyway. the thrustbearing side is worn down like a brake disc.

The cylinder heads are cracked too. got that news already, so I will be going with new ones in 64cc's instead of the old 76cc's....

concerning the old engine mounts, that's already gone and done. used new OEM mounts that bolt to the original holes. thank god the G-Body frames are so well designed, that once you have the right mounting hardware, the correct location shows itself by perfectly ligning up the holes.
 

bracketchev1221

Royal Smart Person
Jan 18, 2018
1,220
113
AT least you have a plan and know the engine wasnt the problem. They generally don’t eat thrust bearings on their own.
 

FluoFerret

Greasemonkey
Thread starter
Apr 2, 2018
184
43
Luxembourg
UPDATE

I drained the fluid from the TH400 as advised. after slowly pouring the fluid in the container for propper disposal, this is what i found at the bottom. and that's just one side of the drain-pan... Looks like I have to overhaul the transmission entirely. i bet there's a lot more in the transmission pan.
20220911_174715.jpg
20220911_174727.jpg
 

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