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Discussion Starter #1
Is there any way I can check if I fully seated my Fmx torque converter when I installed the engine and trans together. I heard two clunks and was able to put a straightedge across the bellhousing and the pilot bushing was not sticking out. I am second guessing myself.
Thanks!
 

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Just some guy
67 coupe, 69 Sportsroof, 86 hatchback
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The final checks are when it's being put on the engine. With a couple of bellhousing bolts stuck in, have a look at the studs. If the transmission is almost up the the transmission they should be just barely sticking through the flexplate. You have to look at them anyway as you must guide them into place as part of the installation. Then tighten a couple of bolts enough the transmission is just up against the engine (IE, gently) and look again. Now they should be through just enough to start a nut on. If so then you can hammer the bellhousing bolts down tight. So to speak. If instead the studs are ALL the way through, stop. Take the bolts back out and back the transmission back off, the converter isn't in. As a very last check after everything is bolted up except the converter nuts, you should be able to grab a converter stud with your fingertips and shake the converter back and forth a little. If these checks seem kind of redundant, well they are. But I still do them every time. Breaking front pumps sucks. Changing transmissions isn't such a very fun thing to do the first time, Having to do it over...

It may be that someone has measured how deep the converter goes but I haven't seen it. Someone did on AOD's and the faces of the stud mounts (what goes flush up against the flexplate_ goes into the bellhousing about 7/8" on those.
I have noted that if you prefilled the converter with a quart of fluid like you're supposed if you keep spinning it after it seats it will start drooling a bit of fluid of a cooling line fitting. Thus letting you know the pump drive (the last clunk) is in fact engaged. It's kind of incidental though and doesn't always happen.
 

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Do a little measuring before bolting up the tranny. I believe 1/16-3/16" is a popular amount of clearance.
20200621_114114.jpg
 

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if the engine has been startet and fluid is comming out of the trans Lines, i guess that is a Way to know its probably seated, because the pump is being driven, - right?..
 

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Discussion Starter #5
I haven’t started the motor yet because I’m not quite at that point.
I checked to see if it would wiggle per GypsyR’s thorough post. It doesn’t.


I am thinking that it is not seated in the pump and I should pull it. Will I have destroyed the pump by mating it to the motor? How do I check the pump?
 

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if the engine has been startet and fluid is comming out of the trans Lines, i guess that is a Way to know its probably seated, because the pump is being driven, - right?..
Not really, if you didn't have it seated and stacked the pump by bolting it up to the engine then it would be too late at that point. good rule of thumb is if you can get a finger behind the converter after seating it then it is not fully seated.
 

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I haven’t started the motor yet because I’m not quite at that point.
I checked to see if it would wiggle per GypsyR’s thorough post. It doesn’t.


I am thinking that it is not seated in the pump and I should pull it. Will I have destroyed the pump by mating it to the motor? How do I check the pump?
You haven't installed the converter nuts yet? You should be able to move the converter at least a little, try using a screwdriver for leverage and see if it moves. Loosen the case bolts a smidge in case it is just a little bound, If not 100% sure it is easier to pull the trans now and try again.
 

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Discussion Starter #8 (Edited)
You haven't installed the converter nuts yet? You should be able to move the converter at least a little, try using a screwdriver for leverage and see if it moves. Loosen the case bolts a smidge in case it is just a little bound, If not 100% sure it is easier to pull the trans now and try again.
That’s correct. Nuts are not on yet. Tried to move it around with a screwdriver and the stud for the nut is bound up against the bottom of the flex plate

will loosening the bellhousing bolts actually give me a sense if it’s in correctly if it is still Tight?
 

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I was just thinking if you loosened the trans a bit and it is still tight or you see the flex plate release pressure then you haven't got the converter set. If that is the case then pull the trans and reseat. If after setting the converter all the way and it spins ok without binding or making noise you might have dodged a bullet.
If you loosen it a tad and the converter can be wiggled then snug it up while still wiggling and perhaps it is just at the very last that it is just firm on the flexplate.
 

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.... the stud for the nut is bound up against the bottom of the flex plate....
All I need to hear. The converter wasn't all the way in. Pull the transmission out or back far enough to diddle the converter some more. MOST of the time a pump gear will survive what you did and what really wrecks them is if the engine is started with it bound up that way.

It's kind of hard to tell if the pump is damaged without taking it apart for inspection. You can pull the converter and try and look down next to the stator at the pump drive gear to see if it has a crack in it. Pumps get broken a lot like this but the way you are describing it my opinion would be that it very likely isn't hurt.
 
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I usually try to support the converter weight and kinda spin it while pushing a little and usually they will pop all the way in after a few spins.
 

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Let's not forget about the drain plug. There's a "special spot" on the flexplate that the plug has to fit into... at least that's how it is on the C4 from what I remember. The bolts will line up even if the drain plug isn't in the right spot... and if you tighten it up with the plug in the wrong spot you'll bend the flexplate. I have a bent one hanging on my wall. It's a nice clock now.
 

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Discussion Starter #14
Let's not forget about the drain plug. There's a "special spot" on the flexplate that the plug has to fit into... at least that's how it is on the C4 from what I remember. The bolts will line up even if the drain plug isn't in the right spot... and if you tighten it up with the plug in the wrong spot you'll bend the flexplate. I have a bent one hanging on my wall. It's a nice clock now.
thank you!! Did it bend when you secured the converter nuts or when you mated they bellhousing to the motor?

that must have been an awful noise when you started the motor.
 

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Discussion Starter #15
Following up on this thread for some closure. Pulled the trans and tried to get the third clunk. Reinstalled trans but nothing changed.

Pulled the engine and Trans out. Took trans to shop to have pump checked. Pump was ok but transmission guy said that converter and/or pump gear needed a little massaging to get pump/converter engaged.

Transmission guy reset the conveyer for me and locked it down with a bar for transport home.

He also mentioned as I was leaving that he Seemed to recall that the FMX has a unique flex plate and that I should check that.

Dang if he wasn’t correct. I had a summit G111-SfI which did claim to fit an FMX. To be safe, I swapped it for a Pioneer FRA-205. Pioneer was .10 Inch thinner.

Measured everything before installing and the measurements told me I had about 3/16 clearance.

Installed today and followed GypsyR’s steps. Converter wiggled before I pulled the nuts tight.

Victory!

Thank you, GypsyR and all who helped!!

All I need to hear. The converter wasn't all the way in. Pull the transmission out or back far enough to diddle the converter some more. MOST of the time a pump gear will survive what you did and what really wrecks them is if the engine is started with it bound up that way.

It's kind of hard to tell if the pump is damaged without taking it apart for inspection. You can pull the converter and try and look down next to the stator at the pump drive gear to see if it has a crack in it. Pumps get broken a lot like this but the way you are describing it my opinion would be that it very likely isn't hurt.
 

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That's certainly good news. You'd have had a mess of problems (like I did) if you hadn't had switched flex plates. Good move.
 
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