Sealing flex plate bolts

1989 FORD MUSTANG
500 MILES • 5.0L • V8 • 2WD • AUTOMATIC
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RPMAGOO
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I recently installed a new 302 Crate Motor with a AOD automatic transmission, and failed to seal the flex plate bolts. the bolts are 7/16-20 and were torqued to 80 ft. lbs. I understand that oil may leak out around the bolts. Will this be a major leak or just a nuisance?
Apr 15, 2019 at 12:47 AM
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ASEMASTER6371
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Good morning,

There is no sealer required for installing these bolts. They just et torqued to 80 lbs.

Only use new bolts. Never reuse these bolts.

Roy
Apr 15, 2019 at 4:08 AM
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RPMAGOO
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I Understand that, on this motor, the holes are not blind holes. They are drilled through, and go into oil, inside the crank case. It's a BluePrint crate motor, and they waned about the potential problem. That's the reason for my concern.
Apr 15, 2019 at 4:39 AM
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ASEMASTER6371
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Okay, then yes. The stock cranks do not require a sealer.

Your does need thread locker. I would use lock tight red in color. That's what we used for cooling system bolts that went into coolant passages.

Roy
Apr 15, 2019 at 4:41 AM
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RPMAGOO
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The motor is in the car. Everything is all hooked up. I'm not sure if we can pull the transmission back far enough to take care of the problem, without pulling the motor, and transmission as a unit. Either way it's a big job. If I live with it, and do nothing, do you think that the leak will be a major one, or just a nuisance?
Apr 15, 2019 at 4:47 AM
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ASEMASTER6371
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More like a nuisance leak. It is not a pressure point.

Roy
Apr 15, 2019 at 4:51 AM
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RPMAGOO
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Thanks. I'll live with it, and see what happens. Have a good day.
Apr 15, 2019 at 4:52 AM
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ASEMASTER6371
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You as well.

Always glad to help.

Roy
Apr 15, 2019 at 5:03 AM
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RPMAGOO
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Got the motor running, set timing etc. ran the motor for a few minutes watching oil pressure, looking for leaks etc. When we shut the motor down, I got under, while the car was still on jack stands. Bad news, there was quite an accumulation of oil in the bottom of the transmission bell. I feel that we must pull the transmission, and seal the flex plate bolts. This is a Ford AOD on a 302 in a 64 Falcon Sprint. I feel that we can pull the transmission without removing the engine. We can just pull the transmission back far enough to get at the flex plate bolts. Of course we must remove the drive shaft, mounts, starter, cables, dip stick tube etc., and loosen the motor mounts to tilt the back of the motor down enough to get at the two top transmission mount bolts. What's your opinion, on this ? Thanks, Dick
Apr 17, 2019 at 9:26 PM
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ASEMASTER6371
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Yes, use two long guide bolts to back up the transmission to gain access to the flex plate.

Roy
Apr 18, 2019 at 12:06 AM
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WAYNE ANDREWS
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I just did the same thing put an 1986 302 and aod transmission in my 1964 Fairlane and I believe I have having the same problem. already pulled the transmission once thinking it was a rear main seal but I think I'm going to have to do it again and use threadlocker on the bolts.
May 31, 2021 at 7:32 PM
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ASEMASTER6371
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Sounds like a plan.

https://www.2carpros.com/articles/transmission-replacement-removal-manual

We have a YouTube video on the removal of the transmission for you to view.

https://www.youtube.com/watch?v=3vJAojsrfuU

Roy
May 31, 2021 at 7:37 PM