flexpate problems threaten labor day vacation..

[Guinness]

Well, this flexplate didnt last either.. its starting to chatter again.

I will have to pull the trans again and think of something else. A buddy said he heard of harmonic balancers causing similar problems. I wonder if the crank has any runout where the flexplate mounts.

If anyone knows what is wrong, please let me know, Im about to wrap it up.

 

[trackspeeder]

A bad thrust bearing can cause broken flex plates. Kind of extreme but can happen.

 

[Guinness]

Where is the thrust bearing???

 

[trackspeeder]

Where is the thrust bearing???

The thrust bearing is the #5 main bearing.

 

[Guinness]

oooooooooooooooooooooooooooooooooouch! Did you just punch me in the nuts? It feels like it..

Anyway to be sure its bad? without doing that plastic gauge ****?

 

[trackspeeder]

oooooooooooooooooooooooooooooooooouch! Did you just punch me in the nuts? It feels like it..

Anyway to be sure its bad? without doing that plastic gauge ****?

No to check this you will need a magnetic dial indicator.Place it on the front of the block.Pry the crankshaft forward. Zero it out. Pry the crankshaft back. check the reading. Do this a couple of times. .020 max wear limit.

This could be the problem if you keep breaking flexplates. Something to think about.

 

[Dogman]

Guinness, I need you to take some pics of the trans. and motor and flex plate together, then a pic of the the flex plate and were it's broken, a pic of the trans. and converter,and a pic of the back of the motor.

theres somethings that will give you a set of problem,

1) is the converter all the way in the pump? you can find this out by, can your hand fit behind the converter? if so the converter is not in all the way. turn the converter till you here two clunks. your hand should not fit behind the converter. this can brake the flex plate at the back of the crank by the flex plate bolts.
2) are all the Dall pin in the back of the motor? if the pins are not there you need to get them.this can cause a misalignment with the trans.and let the trans. shift and flex and brake flex plates.
3) a bad in stall can brake it to. Always, always, bolt the trans. in first before bolting the converter down, make shore the converter is lined up were it needs to go.
4) is this the trans. that was welded on? if so the misalignment MAY be in the trans. housing and there nothing you can do but junk the housing and build a new unit.

What size tires are you running and what gear is in the rear end?
The pic will tell me more.

 

[Guinness]

I dont have any pictures at the moment, I will take some when I take it apart this weekend. Is there anywhere online to get parts diagrams from ford?

Do you know how many dowel pins there are on the back? I hadnt taken notice since my buddy is usally at the front lining it up and I am muscle f'ing it into place.

My buddy surprised me this last time when we were fixing the flexplate at his house and had the trans back in when I arrived.. he just needed help turning the engine over to get the torque converter bolts tightened. To my surprise the engine would not budge - he had tightened down the trans without the converter in the pump all the way. This flexed the flex plate forward 1/2 inch. As we backed the trans bolts off the bell housing was f'n screaming..

We pulled the converter, checked everything out including the flexplate and found the keyed pump drive on the tc which took us a good 10 minutes to line up right. Then we assembled like you said with tc last.

Im not sure what you mean by the trans was welded on? I had a cooler line issue where I couldnt find a bung long enough to get past some stripped out threads toward the back of the trans. I put a pipe thread (tapered) which works perfectly.

Running 3.73 on 37"s, I would have gears by now if it werent for the flexplates setting the gear fund back years..

 

[Dogman]

when you put the converter in turn it till you here 2 clunks then it will be set in the trans. pump. some time when installing the trans. the converter will slide out of the pump. you can put a small plate on the trans. that goes up to the converter and hold it in place.

 

[Guinness]

Thanks guys, I will look into this and get some pictures. I definitely got it seated good.