How much will a ring gear expand when heated? I had to send one back because it would not go on the flywheel. This is for a'59 292 Y block. I think the motor came out of a truck, don't know how big of a truck, it had the truck type mount up front and the truck type front cover also the flywheel takes an 11" clutch. Which brings up another question, does the truck flywheel with larger clutch use the same ring gear as the car motors? It is a 146 tooth gear. I found a ring gear at NAPA that the spec sheet gives an inside dia. The best I can measure, this gear will have to expand about .150" total to go on.
That sure seems like a lot..I'd think more like .005 or so? I replaced one for an L6 Dodge and put the ring gear in the oven @300 and the flywheel in the freezer...took a couple of tries before I was able to get it squarely started, but then just tapped it on.
I've had to heat them with a torch, but the last one (the one that too small and I sent back) I heated with torch and put the 'wheel in freezer, still no go. Wish I had measured that one so I could know if the one from NAPA will be the same.
.150 is a hell of lot to expect that ring gear to expand, even .015 is a lot if it needs to be tight to the flywheel and not slip. I could see if it was .0015 maybe. Might be a misprint on the number or the person at the parts counter doesn't know how to read it!
It has to be a misprint. Before it expanded .150" it would go liquid. Even if it didn't, when it cooled, it would snap.
how did you measure, you got a 15" caliper? i just lay the flywheel on a block and keep going round and round with a torch and it falls off. flip it over, repeat, and it falls on
Ive turned ring gears around. One side will become worn. and you can flip it so that the unworn side is facing the starter. I place the flywheel in the freezer and ring gear in the oven and never had any problem's
I thought about flipping the gear over but would rather get a new one if I can. Tried freezing the flywheel also. I measured with a large caliper, the type that has no dial, just two pointers, then transferred that over to a tape measure. I know this is not the best way to measure but I don't have a dial caliper that big. Anyway the flywheel looks like it is 13.5" . If .15" is too much, and that's what I was thinking, there must be different flywheels for trucks and I keep finding car ring gears.
Yes considering all the work involved in getting to the flywheel a new part is preferable. Ive mostly flipped the ring gear on tractors they are about a inch thick. sometimes a new part just isn't available so you flip it over.
What I'm doing is swapping in a 3 speed and removing a Ford-o-matic in my '30 sedan, so I'm collecting parts now and not in a hurry as the car is still running. I have time to find the correct gear, but I will flip that thing if it comes to it. The old gear must have slipped on the flywheel at some time as it was welded to the flywheel, so if I do reuse it i will have to weld it again.
As I recall from my time spent working in heat treating facilities, a general rule is that steel expands in all directions, .0088" per inch.
so I guess I could take .0088" times that by the cir***ference of the gear, then reduce the result by twice .0088" as the gear would get thicker by that amount at each side. I don't know, would something like that work?
I borrowed a caliper from work and got a good measurement on the flywheel, it is 13.477" so that means that the ring gear must expand .125 total. is that too much?
Looks like the gear would still be too tight by at least .010". You might have to pack the flywheel with dry ice and try to shrink it, but the final interference fit may crack the gear.
Automatic ring gear is different than a manual ring gear . Ring can be removed and changed on a manual flywheel , modern auto can not be changed . Auto needs a new flex plate with ring gear attached (welded) . It’s early and not sure I’m reading your post correctly ,but I think you will never be able to replace the auto ring gear correctly , toss it and find another Sent from my iPhone using The H.A.M.B. mobile app
As stated set the fly wheel on a metal bucket , Heat the ring gear with a torch it will fall off . Flip the flywheel over on the bucket , lay the ring gear on it ,heat with a torch it will fall into place . Allow to cool and good to go Sent from my iPhone using H.A.M.B.
i'm not trying to install an auto trans gear on a manual flywheel. I'm replacing an automatic with a 3 speed trans and just collecting parts for the swap, one of the things I need is a new gear on the manual trans flywheel I have. The problem I have is, I don't know what this flywheel came off of ( well it came off of the motor in the car now but I don't know what it is from before I got it) and I'm having a hard time finding a gear to fit the flywheel. the 'wheel I have is one that takes a 11" clutch, most cars used a 10" clutch, the ring gear that I got for a car was too small, would not go on over the flywheel.
WHAT I DID FIND!! I found a company called Ring gears are us and they list a Ford gear that fits a Customline w/6 cyl, 1955- 1964 V8, F100 w/272, F250 w/292, F500 w/312 and "trucks" w/223 and that gear has a I.D. of 341. Now I guess that measurment is metric and 341mm = 13.425". If all of that is true the gear will only have to expand .052 to fit over the flywheel. The problem is that the Customline is a car right? and other f100's gears that I have found have a I.D. of 13.352" NOT 13.425" SO who is right? I sent them an e-mail.
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