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flexplate hitting something?

At the risk of :dh, look at the following picture:

6417d1109770108-flex-plate-broke-flexplate1.jpg


The torque convertor studs will poke through the 4 holes you see at the 1:00, 4:00, 7:00 and 10:00 positions. The two larger holes at 2:00 and 8:00 are the ones that the drain plugs should be poking through. Your flexplate may have both holes or just one and they may not necessarily be in the same position as the picture. If a drain plug isn't positioned so it pokes through the hole it will push on the backside of the flexplate and bend it outward toward the engine. If this is the case, you'll need to take off the 4 nuts holding the flexplate to the convertor and move the tranny back enough to disengage from the flexplate and turn the engine 90, 180, or 270 degrees until the drain plugs stick through the holes.

This is such a common issue that I want to be sure this isn't what you're experiencing.

Frank
 
frank, thanks for the pic and explanation. i took a really good look at those bolts and they're all in the appropriate location and all the nuts are clear of any damage and look to be counter sunk properly.

ok, so i talked to a guy at a local stang shop and he had the same problem and discovered he was missing a shim on the crank and it's this shim that i think i'm missing. i took this picture of the back of my orig 289. i'm trying to remove this circular "thing" at the end of the yellow pointer...but is this just the end of the crankshaft? i can't get this thing off! i have a local parts yard that says they have this "shim" or spacer that i need and i'm going to try to pick one up tomorrow. the reason i'm so fixated on this shim/spacer issue is just because the clearance between the counterweight and blockplate is soooo tight. i don't think it should be that close.
 
I don't remember a shim between the flexplate and crankshaft, but there IS a load spreading ring that goes under the bolts. It keeps the flexplate from cracking around the bolt heads.

Are you sure the torque convertor is seated fully in the transmission? I read once that if you can slide your hand behind the convertor it's not fully seated.

Frank
 
"crustycurmudgeon" said:
but there IS a load spreading ring that goes under the bolts. It keeps the flexplate from cracking around the bolt heads.
Click to expand...

This is correct. Many people mistake it for a shim that goes between the flexplate and the crank. It should go on the outside of the flexplate (towards transmission). What you are pointing to with the yellow thing is the end of the crank.
 
Are you sure the torque convertor is seated fully in the transmission?
Click to expand...

Another good point Frank. It's VERY easy to NOT fully seat the torque converter when installing it onto the transmission.


If the TQ converter wasn't seated onto the input shaft..... it would have been a bear to mate the bell housing to the rear of the engine block. So much so that tightening the bell to block bolts would result in "bending" the flex plate forward. The flex plate isn't going to bend much, but if the OP had a gap between the bell and the rear of the block that would only close by tightening down the bolts... it could be enough force on the face of the flexplate to force it into contact with the blockplate.
 
frank, i think you're right. i went to a wrecking yard that specializes in mustangs, A & M Wrecking, in Rio Linda, and the owner, Jeff Guy, couldn't be more pleasant and informative. we talked about the possibility of a shim or spacer....he gave me one, but didn't think that it was the solution. he said that he didn't remember fords needing to be shimmed. anyway, he brought up this torque convertor issue and i do recall that my buddy had a hard time seating the convertor. he did recommend that i pull the trans and check the convertor to see if the flange is "squished", indicating that i was forced into place. so....thank you all again for all the awesome tips. i was hoping to not have to pull the trans, but i'm going to have to do it anyway and restart. i'm also concerned that my flywheel may be bent or that the forced convertor may have damaged the pump. wish me luck. i'll try to take pics.
 
ok, so I'm going to tackle this trans removal tonight and was wondering.....while I'm at it...should I install a shift kit AND a new higher stall converter? anyone recommend a particular one?
here's the specs for the motor:
late model 302 short block, 9.5:1
gt40-P iron heads
E-303 cam
1.7 roller rockers
air-gap/rpm intake
demon 625 carb
tri-y headers
2.79 open diff rear.
i plan on running the stock 14" wheels until i can get 17's. i've read some info on TCs and i think the "mild" street ones are where I should be...around 2500-2900 rpm. if not stated earlier, this is the orig C4 in the '67 coupe. thanks everyone!!
 
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