flex plate backwards?
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Joined: Jul 2001
Posts: 401
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From: Surrey,BC,Canada
Car: 1989 Trans Am GTA
Engine: 5.7L 600cfm carb
Transmission: 700R4 (auto)
flex plate backwards?
i have 2 questions, whats the difference bettween a flywheel and a flex plate? and i just finished droping my rebuilt engine in and bolting it to the bell houseing of the tranny. but i cant get the torque converter to bolt on to the flex plate. my counter weight is faceing towards the engine. i have a baaaaad feeling that i might have screwed myself big time here because i just took back the engine hoist that i rented. i have a 5.7L 89 t/a wich i am converting to carb (from tpi) the part wich the torque converter is suppost to bolt into are bumped out a bit farter than the rest of the flex plate and make a ridge that the torque converter bolt holes cant get over. this is a major problem because i have spent all day screwing with it with no progress.
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Joined: Jul 1999
Posts: 17,265
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From: 51°N 114°W, 3500'
Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
Flywheel is a huge heavy chunk of steel that a clutch bolts to. A flexplate is a simple lightweight plate with a ring gear that a torque converter bolts to.
It is possible to install a flexplate backwards. If it's on backwards the starter either won't engage at all because the ring gear is too far away or won't disengage because the ring gear is too close. If you measure the space between the end of the starter drive gear and the ring gear there should be .100" +/- .040".
You should also be able to slide the converter back into the tranny allowing enough room to spin the converter without hitting the flexplate.
If you do decide the the flexplate is on backwards you can pull the tranny easier than pulling the engine.
It is possible to install a flexplate backwards. If it's on backwards the starter either won't engage at all because the ring gear is too far away or won't disengage because the ring gear is too close. If you measure the space between the end of the starter drive gear and the ring gear there should be .100" +/- .040".
You should also be able to slide the converter back into the tranny allowing enough room to spin the converter without hitting the flexplate.
If you do decide the the flexplate is on backwards you can pull the tranny easier than pulling the engine.
Joined: Mar 2000
Posts: 43,187
Likes: 42
From: Littleton, CO USA
Car: 82 Berlinetta/57 Bel Air
Engine: L92/LQ4 (both w/4" stroke)
Transmission: 4L80E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
Sounds like the torque converter isn't engaged in the front pump. You'll probably have to loosen the bellhousing bolts at least a little to be able to move the TC around enough to get it to go in. You can't do it as it is, because the pump is turning with the TC now (even though the tangs aren't engaged).
There should be about a 1/4" of clearance between the TC and flexplate, when the two are aligned with where the bolts insert, when the bellhousing is up snug and the TC is properly engaged with the pump.
There should be about a 1/4" of clearance between the TC and flexplate, when the two are aligned with where the bolts insert, when the bellhousing is up snug and the TC is properly engaged with the pump.
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Joined: Jul 1999
Posts: 18,457
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From: Loveland, OH, US
Car: 4
Engine: 6
Transmission: 5
I agree with five7, it sounds like the TC isn't in all the way. It also sounds like the flex plate is on the right way.
Take out all the BH bolts except one on each side; put about 6" long ones in those; and slide the trans back as far as you can get it to go. That should give you enough clearance to do what you need to do without having to completely pull anything.
Take out all the BH bolts except one on each side; put about 6" long ones in those; and slide the trans back as far as you can get it to go. That should give you enough clearance to do what you need to do without having to completely pull anything.
Joined: Mar 2000
Posts: 43,187
Likes: 42
From: Littleton, CO USA
Car: 82 Berlinetta/57 Bel Air
Engine: L92/LQ4 (both w/4" stroke)
Transmission: 4L80E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
Be sure to support the engine and tranny when you do this. A board under each oil pan with a jack under each board should do the trick.
Thread Starter
Member
Joined: Jul 2001
Posts: 401
Likes: 0
From: Surrey,BC,Canada
Car: 1989 Trans Am GTA
Engine: 5.7L 600cfm carb
Transmission: 700R4 (auto)
6" bolts
hey that 6 inch bolt idea sounds good, i can probly use the long bolts off my engine stand right? do i have to remove the drive shaft? or does the tranny just slide back a bit farther into it?
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