Flexplate to torque converter gap
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Pro
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From: Ventura County CA
Flexplate to torque converter gap
When I move the torque converter up against the crankshaft I have 3/16" gap between the flexplate and the torque converter mounts. Is this too much gap? should I use a 1/16" or 1/8" spacer in there?
ZZ502 with factory flex plate and TH400 with 3500 stall converter.
Thanks
Also, what is the torque on the bolts? they are 3/8"-16.
ZZ502 with factory flex plate and TH400 with 3500 stall converter.
Thanks
Also, what is the torque on the bolts? they are 3/8"-16.
Last edited by MBrianB; Mar 30, 2019 at 05:07 PM.
Le Mans Master
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From: League City Tx
With the torque converter pushed ALL the way into the TRANSMISSION pump, bottomed out.... you should have at least 1/8" of clearance between the flexplate and converter mounts...3/16" would be better. Usually if you have a 1/4" gap, its wise to add a small spacer.. I used some 1/8" flat washers and measured them with a caliper to make sure they were the same size.
Make sure the converter has clicked 2-3 times when pushing it into the pump as you spin it.
Make sure the converter has clicked 2-3 times when pushing it into the pump as you spin it.
Last edited by ajrothm; Mar 30, 2019 at 05:56 PM.
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From: Ventura County CA
When pushed towards the transmission I have 5/16" space. When the converter is pushed towards the engine and has made contact with the crank shaft there is 3/16" of space remaining between the converter and the flex plate. The flex plate is OEM and installed correctly. The converter is new, that's all I know about it. I will try to read the numbers on the converter.
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all the way, up to the shoulder of the converter. no shiny parts are visible. There is no side to side play in the snout while in the end of the crank.
Last edited by MBrianB; Mar 30, 2019 at 07:51 PM.
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Make sure the flex plate is on correct, if it is you can contact the company that made the converter or just shim the mounting tabs. I have shimmed some in drag cars with no issues.
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Thanks Gunfighter, I have read on other forums that there should be some "pull" to the converter flexing the flex plate keeping a pre-load on the snout into the crank. With only about 2-3/16" remaining how should I shim it. Add 1/16, 2/16 or fill the gap with 3/16" shims with no preload on the flex plate?
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Thread Starter
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From: Ventura County CA
The side facing the engine is stamped "This Side Toward Engine" at least that part is correct.
Summit sells spacers so this is not the first time this problem has come up. I will try them and hope for the best.
Summit sells spacers so this is not the first time this problem has come up. I will try them and hope for the best.
Pro
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From: Texas
You can go to most parts stores and find some washers that will work.
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Safety Car
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From: South Florida
Yep drill bit leaves, converter comes forward that distance. That is the recommended distance from the converter manufacturer iirc
also saw it in this thread by chance
https://ls1tech.com/forums/automatic...important.html
also saw it in this thread by chance
https://ls1tech.com/forums/automatic...important.html
Le Mans Master
Joined: May 2006
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From: League City Tx
So the snout on the converter is hitting the crank before the converter mount pads are touching the flex plate? If so, there is something wrong. You do NOT want the converter snout bottomed out in the crank. Usually the pads will touch the flex plate before the snout bottoms out. You do NOT want any preload on the crank. You WILL knock the thrust out of the motor under load. Remember the converter will push forward under heavy load, putting load against the flex plate/crank. That’s why you initially leave a 1/8-3/16” gap to allow for the “swelling” under load.
Be very careful here, you can easily wipe out the thrust/main bearing in the motor if this is not right.
Be very careful here, you can easily wipe out the thrust/main bearing in the motor if this is not right.
Le Mans Master
Joined: May 2006
Posts: 9,993
Likes: 1,136
From: League City Tx
If there is 5/16” gap between the converter pads and the flex plate, then you’ll need some 1/8” washers to tighten the gap up some. That should leave you 3/16” clearance. That’s fine and plenty of engagement left in the pump when you pull it foward. It’s better to have more clearance then not enough.
Put the 1/8” washers in it, pull the converter forward and check to see if the snout is contacting the crank. It should slide in the crank but not bottom out inside of it. Also look at the converter shank at this point in the trans pump and make sure it’s not too much hanging out.
Almost sounds like the converter snout is too long or something if it’s bottoming out in the crank before the mount pads touch the flex plate.
Put the 1/8” washers in it, pull the converter forward and check to see if the snout is contacting the crank. It should slide in the crank but not bottom out inside of it. Also look at the converter shank at this point in the trans pump and make sure it’s not too much hanging out.
Almost sounds like the converter snout is too long or something if it’s bottoming out in the crank before the mount pads touch the flex plate.
Last edited by ajrothm; Mar 31, 2019 at 06:39 PM.