Mercury 312 flex plate
 

Hi guys, brand new to this y block malarkey, a flathead man. I need on my 56 mercury monterey 312 auto a flex plate and a Bell housing. It might sound obvious but I know nothing about such things, i in Macs I,v seen a flex plate for a Fordamatic 312, is it the same as a mercomatic ?....the teeth on my flexplate are wrecked, is a replacement fitted with the teeth or a separate thing, here in the UK this stuff is hard to find. Any help of location of these things would be appreciated...many thanks.

Re: Mercury 312 flex plate
 

If you need the STARTER RING GEAR, it is located on the converter cover (BPN 7950), not the flex-plate.

We need to know if the TRANS is AIR-COOLED or COOLANT-COOLED. There is also an updated flex-plate you might consider as the original has service problems and you will have the trans out.

Any questions, please fell free to ask.

Re: Mercury 312 flex plate
 

The Merc had the medium case MOM/FOM in 1956. The 56 T-bird may be same. This was a cross over year for air and liquid cooling change. The air cooled torque converter has a finned aluminum outer main case.

Re: Mercury 312 flex plate
 

Photo 1, a '55/early'56 air-cooled style torque converter, with ring gear.

Photo 2, an air cooled bellhousing for a '55/early '56 Fordomatic, two rear facing air vents.

Photo 3, improved replacement & '57+ style flex plate.

Image 4, showing the reinforcement rings for the 'new' flex plate, installed between the bolt heads and the flexplate.
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Re: Mercury 312 flex plate
 

https://www.fordbarn.com/forum/attac...p;d=1645495009

https://www.fordbarn.com/forum/attac...p;d=1645495013

Flex Plate on my 1956 Mercury Monterey - showing both sides

Re: Mercury 312 flex plate
 

https://www.fordbarn.com/forum/attac...p;d=1645510904

1956 Mercury Torque Converter

Re: Mercury 312 flex plate
 

Thanks so much guys , been very helpful. So I,m looking to BUY JUST A BOLT ON RING GEAR ? Any idea where I can purchase one ? Any idea of a part number ?
The gearbox etc is together and in the car at the moment so I have no idea what it looks like and if its air cooled or water cooled....would it be the same ring gear for both ? Many thanks.

Re: Mercury 312 flex plate
 

Spent hours on tinternet and here in the UK no chance of getting the auto ring gear required. Plenty in the US selling for manual gearboxes not Auto....tried Rock Autos, the same, can anybody help locate a supplier ? All help would be most appreciated, many thanks.

Re: Mercury 312 flex plate
 

The RG is part of the CONVERTER COVER ASSY. There is no separate RG for an AT.

You need B5A 7950-A for either the AIR or COOLANT COOLED converter.

Re: Mercury 312 flex plate
 

Many thanks my friend.

Re: Mercury 312 flex plate
 

https://www.fordbarn.com/forum/attac...p;d=1645572567

Auto Trans Specs - 1956 Mercury

Re: Mercury 312 flex plate
 

Did you retain the older style flex-plate on yours MERC-MAN?

Re: Mercury 312 flex plate
 

There are two O-rings for the cover. One large one and a smaller one. Pulling the cover off may require o-rings too.

Re: Mercury 312 flex plate
 

CASCO Thunderbird parts lists a correctly re machined ring gear for $75. Other Thunderbird vendors show them for about half that price, but I suspect they are part of a run made several years ago that, although useable, did not fit very well. As noted above by Rotorwrench you will need seals to reassemble the converter. If you choose to go this route be sure to get seals with square profile cross section as original. (some sell round ones, not good!) The ring gear will need to be pressed, sweated, onto the converter cover and then reinforced with spot welds as shown in enclosed picture.
Attachment 484911

If all the teeth are still intact and the welds look like this..
Attachment 484909

...and not like this..
Attachment 484908

...then an alternative solution may be to use a replacement type high torque starter that engages the ring gear on the opposite side to the original type starter...
Attachment 484910

I believe there is also a starter from an FE engine that engages on the still good side of the ring gear, though I do not know from what year or model it was fitted. Some research on a Crown Victoria or similar forum should yield a result to that end.

Good Luck. Very nice car.

Re: Mercury 312 flex plate
 

Thank you guys , your advice has been invaluable.....my head is still swimming though.