Ford-o-matic converter position

[46international]

I did a search, did not find the answer.

I'm mating a 292 Y block to a Ford-o-matic and bought the flex plate from Mac's, it came with shims/ spacers. I guess they are for positioning the converter correctly, what is the correct way to do this? where do the spacers go?

 

[JeffB2]

This might be a good place to check too:http://www.network54.com/Forum/260730/

 

[Dominic Hide]

The flexplate goes against the crankshaft flange. The rings go on the outside and spread the clamping load so as not to cause the flexplate to crack between the mounting holes.
Some after market flexplates came with a single thick ring, some with two thinner ones. Most original cars had three that were thinner still. All three options have the same total thickness and must be used complete. Failure to do so will allow the bolts to protrude too far through the crank flange and make contact with the lower rear seal retainer.

 

[46international]

Thanks, "hide"

 

[Hot Rod Reverend]

Ditto to what Dominic said - he is spot on! Some guys make the mistake of thinking those rings are shims for spacing. They are there to reinforce, not space, so they actually go on the side of the flexplate to which you would see the bolt head and not the other way around like most folks think they would.

 

[Daves55Sedan]

And if you put it all back together without those "shim" spacer plates, the bolts thru the back crankshaft hub will protrude into the back of the engine cavity. When you first try to turn the engine over, it will crank until one of the bolts hits the engine bottom flange. You're not going anywhere.

 

[Daves55Sedan]

BTW, Don't forget to align the balance mark on the converter housing with the mark on the front of the flywheel plate. If these marks are not aligned, your converter will rotate out of balance, possibly wear the converter hub to front pump seal and other even more serious damage.

 

[alamore]

Hello my name is Al and I'm replacing the flexplate on my 55 Fairlane Club Sedan. My car had the flywheel with the two spring steel riveted plates that served as a flexplate (3 holes each side).

I purchased the replacement one piece flexplate from Macs but I am not sure if the old flywheel is supposed to remain bolted to the crankshaft flange (along with the new flexplate bolted in next to it), or if I should remove the flywheel completely and just use the new flexplate by itself. I would think that the flywheel should stay but am not sure.

To get some info on this I looked at the 1955 and 1957 fordomatic manuals and its not clear whether or not the old flywheel should stay. some illustrations seem to show that the flywheel stays and others not. Any info you can provide would be appreciated, Thanks, Al Amore

 

[KULTULZ]

The new flex-plate is a 1957 design that replaces the 55/56 design.

The replacement flex-plate is used only. Don't forget the (3) reinforcing rings install.

Nice of the sellers not giving assembly detail.

 

[Daves55Sedan]

its not clear whether or not the old flywheel should stay. some illustrations seem to show that the flywheel stays and others not.

Okay, let me answer it this way; The '56 and older Ford-O-matics had an air cooled converter incorporating a thick (probably about 3/16 to 1/4" thick), heavy front plate with ring gear welded to it. That front converter plate is heavy enough to serve as a flywheel all on it's own.
The replacement flexplate offered by repro parts suppliers today is the same design as the '57 and newer Ford-O-Matics. That flexplate is very thin, probably about 1/16 inch thick, but they were used for the water-cooled converters that had a separate flywheel with ring-gear.
So for '55 & 56 models with air-cooled converters, remove that big old heavy flexplate with the riveted tabs and discard. Replace with the newer design '57 flexplate and center rings.
I suggest installing with the stack of bolt-rings behind the flexplate and look under the engine to see how far your bolts poke thru. Rotate the crankshaft to make sure bolts don't hit the bottom flange of the engine block. If they do, you may need to get shorter bolts.

 

[dmsfrr]

Ditto to what Dominic said - he is spot on! Some guys make the mistake of thinking those rings are shims for spacing. They are there to reinforce, not space, so they actually go on the side of the flexplate to which you would see the bolt head and not the other way around like most folks think they would.

. . .
I suggest installing with the stack of bolt-rings behind the flexplate and look under the engine to see how far your bolts poke thru. Rotate the crankshaft to make sure bolts don't hit the bottom flange of the engine block. If they do, you may need to get shorter bolts.

I think Dominic & HRR may be right about the rings being on the bolt-head side but I can't find a diagram in the book I just looked in.

Whether the rings are one one side of the flexplate or the other won't change the overall distance to & thru the crankshaft flange. But if the bolts are too long they will catch on the back of the block.
.

 

[KULTULZ]

Here's an earlier thread that should explain it all - https://www.fordbarn.com/forum/showthread.php?t=260429

As for the reinforcing plates, there are three used. I believe there is one before the plate and two after, but don't quote me on this (you really need the FORD FM SHOP MANUAL for exact assy details). There were three on the old plate weren't there? Do you remember how all came apart?.

Once you put the plate against the convertor cover, it should become obvious how it all goes together.

The large holes are for the convertor drain(s) of course.

B9AZ 6A366-A PLATE - FLYWHEEL REINFORCING - 4" OD - 2.43" ID - .060" Thick

On this particular design, the RG is attached to the torque converter cover - Basic PN 7950, not the flex-plate or flywheel.

There is most likely a FORD TSB of the period discussing the upgrade.

 

[alamore]

OK, thanks all for the info, it's very clear now. I'll also make sure that my bolt protrusion through the crankshaft flange is the same with the new plate as it was with the old and will use all three of the reinforcing rings. I appreciate all the followup coming in so quickly, Al Amore

 

[Daves55Sedan]

I think Dominic & HRR may be right about the rings being on the bolt-head side.

That is correct; flexplate mates to crankshaft flange, then rings go behind flexplate (normally).

Whether the rings are one one side of the flexplate or the other won't change the overall distance to & thru the crankshaft flange. But if the bolts are too long they will catch on the back of the block

That is correct, and the '55 bolts might be longer due to the thicker flexplate it originally had. I suppose one could grind 1/16 inch off the end of those bolts if needed to make sure the ends don't hit the rear engine block flange.

 

[My Old Blue]

My thanks to the OP for starting this thread and the reference link to the earlier thread by KULTULZ. I had NO idea this was a topic. So thankful to you all that lend the expertise and insight. I honestly would have bolted up the original heavy flexplate and installed trans back in and not had a second thought, only kick myself that I would found this thread after all said and done.

I do have a question: Why was the flexplate updated in 57? Was it because 57's went water cooled so the thinner flexplate whereas my air-cooled needed the heavy plate? Then ultimately it was discovered the 57 plate worked better for air-cooled converters?

 

[KULTULZ]

I do have a question: Why was the flexplate updated in 57? Was it because 57's went water cooled so the thinner flexplate whereas my air-cooled needed the heavy plate? Then ultimately it was discovered the 57 plate worked better for air-cooled converters?

The actual reason (and assembly detail) will (most likely) be found in a SERVICE LETTER of that period. My guess is engineering made a better design product for the 57 model year and retro-fitted to the 55 and 56 models as a result of improved engineering and parts cost.

Water cool began at the beginning of the 1956 model run on the MERC and BIRD and APR 56 on the FORD.

I can find no info in either the SHOP MANUAL or TRANS MANUAL, so it has to be within a SERVICE LETTER.

 

[Hot Rod Reverend]

My thanks to the OP for starting this thread and the reference link to the earlier thread by KULTULZ. I had NO idea this was a topic. So thankful to you all that lend the expertise and insight. I honestly would have bolted up the original heavy flexplate and installed trans back in and not had a second thought, only kick myself that I would found this thread after all said and done.

I do have a question: Why was the flexplate updated in 57? Was it because 57's went water cooled so the thinner flexplate whereas my air-cooled needed the heavy plate? Then ultimately it was discovered the 57 plate worked better for air-cooled converters?

My take: the two ear design of pre-57 flex plates did not hold up to the increased horsepower over time. The rivets holding the ears would come loose from the plate, making the converter oscillate back and forth. On my old 55 it was so bad you could hear it. I have seen other pre-57 flexplates where the ears were beginning to shear from the stress.

I have not the library that Kultulz and others possess lol, so this is my theory because of what I have personally experienced and have seen from others over my lifetime.

 

[KULTULZ]

My take: the two ear design of pre-57 flex plates did not hold up to the increased horsepower over time. The rivets holding the ears would come loose from the plate, making the converter oscillate back and forth. On my old 55 it was so bad you could hear it. I have seen other pre-57 flexplates where the ears were beginning to shear from the stress.

Agreed ...

It looks like a poor design from the get-go.

 

[bfdinardo]

As per the other thread posted by KULTULZ, what seemed the best to me was 1 spacer between the new thinner flexplate and the crank and then 2 between the flex plate and bolt heads. this set the plate at the perfect position to be just kissing my torque converter/ring gear to bolt to it. I think if I would have put the flex plate directly against the crank and had all 3 rings on the bolt head side, the flex plate would have had to been flexed (for lack of a better term) the thickness of the ring (0.060") to reach the torque converter.

Note I have a 1956 ford victoria with 292 and fordomatic.

 

[KULTULZ]

As per the other thread posted by KULTULZ, what seemed the best to me was 1 spacer between the new thinner flexplate and the crank and then 2 between the flex plate and bolt heads. this set the plate at the perfect position to be just kissing my torque converter/ring gear to bolt to it. I think if I would have put the flex plate directly against the crank and had all 3 rings on the bolt head side, the flex plate would have had to been flexed (for lack of a better term) the thickness of the ring (0.060") to reach the torque converter.

Note I have a 1956 ford victoria with 292 and fordomatic.

I came across the assembly procedure on another forum and cannot remember where I saw it.

I still want to see the SERVICE LETTER though.