Flywheel housing

B

Borninthefifties

Member
Aloha all, New to the Model A world and really not much of a mechanic but I need very explicit directions for replacing the flywheel housing on my 1931 coupe. Thanks for any help.
 
Flywheel housing are subject to "lateral cracks." Usually at the 9 and 3 oclock positions. Some think these a big deal. Others have driven with a cracked housing FOR YEARS and this has not presented to them a problem.

Uncracked USED flywheel housings are still around. Run $75-$250 with better prices at places other than Ebay.

NEW housings are available, usually starting in the $450 range - but can be more.

Berts might be a source at a good price for either.

Or run what you have. I have NEVER heard of a cracked flywheel housing progressing to disaster while driving.

And don't try the fools errand of trying to weld or braze a cracked housing. Sort of like trying to braze shut a cracked cast iron pot. Unless you can get the WHOLE housing up to welding temp, it will crack on cooling - and maybe even if you can.

Joe K
 
Yep, that manual is a good thing to have hanging around.

I'm one that prefers to remove the rear end and transmission. I leave the spring attached to the axle. Some prefer to leave the spring attached to the frame, but, that spring is dangerous.
 
Unless you have one that has completely failed which I have never seen leave it as is. Your housing is now stress relived. How many "A"s are out there with cracked housings that the owners don't know about. If you study a housing and take in the transmission clutch housing bolted in place I cannot see where there would be a problem.....However I am sure there is one out there in pieces on the ground.
 
I stitched a couple together and they looked very solid but didn't have the ring of the un-cracked, still a sort of dull thud sound, but I would use either one with nary a thought, Both had come out of good running cars. I think most are cracked and the driver is un-aware of it. Probably been cracked when someone raised the front of the engine without unbolting the rear mounts, would be my guess. Never seen a problem from one except the "nervous Nellie" reaction to knowing it is cracked.
 
One of the questions that seldom comes up is the why of the cracks. I've had a long held theory and it is a flaw in the design where there is no support for the bottom half of the housing. This was remedied with the Model B where the bottom half of the transmission is tied directly to the oil pan. The engine/transmission assembly behind the Model A mounting is quite long and unsupported. The thrust of the torque tube on power and braking stresses the unsupported transmission at the flywheel housing. The location of the cracks is totally predictable making shopping quite easy. There seems to be no catastrophic result from the cracks, but many A owners don't want to assemble broken parts, making the best that is to be found very desirable. Too many others care less. The designers of the Float-A-Motors include a rear support that is commonly omitted becaust the purpose is not understood. With the value of the common Model A in decline, the incentive to do right tracs with it. Good Luck: Fred A
 
Joe K said:
Flywheel housing are subject to "lateral cracks." Usually at the 9 and 3 oclock positions. Some think these a big deal. Others have driven with a cracked housing FOR YEARS and this has not presented to them a problem.

Uncracked USED flywheel housings are still around. Run $75-$250 with better prices at places other than Ebay.

NEW housings are available, usually starting in the $450 range - but can be more.

Berts might be a source at a good price for either.

Or run what you have. I have NEVER heard of a cracked flywheel housing progressing to disaster while driving.

And don't try the fools errand of trying to weld or braze a cracked housing. Sort of like trying to braze shut a cracked cast iron pot. Unless you can get the WHOLE housing up to welding temp, it will crack on cooling - and maybe even if you can.

Joe K
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Joe, I think this gentleman's housing is cracked up around the starter and he has already purchased a brand new one from Snyders and just wanted to know the procedure of replacement.


Since you mentioned repairing them with braze, I thought I would mention that I have seen it done successfully by my dad and others from way back in the 60s. A year or so ago I had the engine out of a car that my dad did from back in the late 60s and the repair was still sound. My dad's method was to drill a hole at the end of the crack and he would take a big old grinder and put a vee groove down along the weld. (This was before the days of die grinders and from what I remember as a kid, it looked like a hack job.) Then he would put a bag of charcoal briquettes in the BBQ and build a fire. Then he would place the housing down onto the briquettes and put the lid on the BBQ. After awhile he would get the housing out and braze up the crack. When he was finished he put the housing back onto the ashes in the BBQ and put the lid back. He would leave it until the next morning. Sometime in the night the ashes went out and it cooled. I have heard of others doing it similarly, so it is successfully done that way. Personally, we stitch them today because it is faster but I see no reason why they could not be brazed instead with success.
 
I have what I think is a late 31 housing and it has some reinforcement designed into it to prevent it from cracking. I think Henry made the change.
 
BRENT in 10-uh-C said:
Joe, I think this gentleman's housing is cracked up around the starter and he has already purchased a brand new one from Snyders and just wanted to know the procedure of replacement.

Since you mentioned repairing them with braze, I thought I would mention that I have seen it done successfully by my dad and others from way back in the 60s. A year or so ago I had the engine out of a car that my dad did from back in the late 60s and the repair was still sound. My dad's method was to drill a hole at the end of the crack and he would take a big old grinder and put a vee groove down along the weld. (This was before the days of die grinders and from what I remember as a kid, it looked like a hack job.) Then he would put a bag of charcoal briquettes in the BBQ and build a fire. Then he would place the housing down onto the briquettes and put the lid on the BBQ. After awhile he would get the housing out and braze up the crack. When he was finished he put the housing back onto the ashes in the BBQ and put the lid back. He would leave it until the next morning. Sometime in the night the ashes went out and it cooled. I have heard of others doing it similarly, so it is successfully done that way. Personally, we stitch them today because it is faster but I see no reason why they could not be brazed instead with success.
Click to expand...

Thanks Brent - you described well the trial of actually welding or brazing a housing. Given the time given by your Dad then times the time value of money since then there is no doubt even a new housing reproduction would be better investment.

Metal stitching is not new technique and I'm surprised you mention it - doesn't stitching require more "meat?" We used metal stitching on some uber ID Fan bearings at the power plant to good effect (to save TOTAL disassembly of the fan) and I was impressed with the company literature. The price was impressive too, but disassembly was MORE impressive financially.

I think ultimately for Model A users the best advice is "use the best housing available to you." He (the OP) may have had issues other than the 3 & 9 cracks, but he should know to not take a potential step backwards. The object in rebuilding is to minimize the unknown to limit possibility of re-rebuilding. I mean, its a labor of love - but love repeated is only still labor.

Joe K
 
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