help with ring gear ford 8n

[DanielW]

I, too, am wondering where these ill-fitting ring gears are coming from. I currently have the flywheel off my Case 188D while it is out for repair and the ring gear shows some wear in a few spots so I'm considering replacing it. Has anyone had the same problem with the 188?
If so, I guess I'd better plan on stitch-welding it.

Nope, I don't think it's a problem on anything but the N's. While every other ring gear just gets shrunk on a flywheel of constant diameter, the N's all have the ring gears sit over a little step machined on the flywheel. So when you're heating and installing them, it's not just a few thou interference fit you have to overcome by thermal expansion, it's a few thou interference, plus about 10 thou of step on the flywheel. They thus have to be heated far hotter than most, and are often much more of a pain to install than any other ring gears. The ring gears for N's that work best are ones that require you to pull it out of your oven and heat it even more with a rosebud/torch as you quickly take it to your flywheel and put it on. But even so, to be able to get them over the step at all, they have to make the final interference less than all other ring gears, and thus a little more likely to slip if either the flywheel or ring's tolerance is slightly out.

Cole's Notes: The ring gear on your 188 will be easier to install, and much tighter than any N. You'll have nothing to worry about. No stitches necessary. I put ring gears on 188's in a Case 530 and our 630 (and many other engines) without issue.

Someone on another forum once said that the flywheel OD machining on the N's wasn't consistent, and in the original plant they had a selection of ring gears of slightly different inside diameters in order to be able to choose the size that gave the proper interference. I've never heard that anywhere else, however, and doubt the truth of that a little. I do know that the problem seems to be much more common on the 9's and 2's than on the 8's.

 

[WilBury]

Alrighty, thanks for enlightening me gentlemen!

 

[Hobo,NC]

Nope, I don't think it's a problem on anything but the N's. While every other ring gear just gets shrunk on a flywheel of constant diameter, the N's all have the ring gears sit over a little step machined on the flywheel. So when you're heating and installing them, it's not just a few thou interference fit you have to overcome by thermal expansion, it's a few thou interference, plus about 10 thou of step on the flywheel. They thus have to be heated far hotter than most, and are often much more of a pain to install than any other ring gears. The ring gears for N's that work best are ones that require you to pull it out of your oven and heat it even more with a rosebud/torch as you quickly take it to your flywheel and put it on. But even so, to be able to get them over the step at all, they have to make the final interference less than all other ring gears, and thus a little more likely to slip if either the flywheel or ring's tolerance is slightly out.

Cole's Notes: The ring gear on your 188 will be easier to install, and much tighter than any N. You'll have nothing to worry about. No stitches necessary. I put ring gears on 188's in a Case 530 and our 630 (and many other engines) without issue.

Someone on another forum once said that the flywheel OD machining on the N's wasn't consistent, and in the original plant they had a selection of ring gears of slightly different inside diameters in order to be able to choose the size that gave the proper interference. I've never heard that anywhere else, however, and doubt the truth of that a little. I do know that the problem seems to be much more common on the 9's and 2's than on the 8's.

As you say installer error with the most common error not tooled up for the job. Why take the chance when its not going to break the bank pay someone that has the tools and knowledge to preform the job.

There is a local X NAPA store/machine shop in my hood that does small engine repairs their mechanic is a good one. They work with nuttin what tools they have are worn slap out he is not tooled up to do flywheel ring gears that does not slow him down he takes them on and will fudge it up. All the N flywheels they tackle end up at my shop with its a part issue. Its not its installer error.

DIY folks beat and bang on their chest I did it heating it in a oven, camp fire, propane torch, BBQ grill they just got lucky.

The pix JMOR posted is mine it came to me slipping it was installer error. There is no doubt in my mind that NAPA store installed the ring gear in that flywheel.

 

[WilBury]

Tooled up...
You mean a flat table, sheet of asbestos, heavy asbestos gloves, a well supplied rosebud & a temp stick?

 

[DanielW]

Tooled up...
You mean a flat table, sheet of asbestos, heavy asbestos gloves, a well supplied rosebud & a temp stick?

For pretty much all other ring gears except the N's, you don't even need to get that crazy. It's just the extra step/ridge on the N's that require more heat than typical. Usually you get the ring gear nice and hot in a conventional oven cranked up nice and toasty (450-550 degrees usually does it). Make sure it's been in for long enough for the heat to soak and get the whole thing expanded. Have the flywheel sitting nearby on a solid surface, with the outside free of burrs and cleaned up with no oil/residue on it. A good pair of gloves/tongs to take it out of the oven and drop it on asap, and you're good to go. Not a bad idea to have a brass hammer or mallet handy in case it starts shrinking too fast or gets slightly cockeyed and needs a few gentle taps to get it home before it cools too much, but even that's not typically necessary.

The rosebud/torch heating that's required for the N's is something you want to avoid for other ring gears if possible: The N rings usually need to be heated to 600+ to even have a chance of slipping over, and at those temps you're harming the temper of the teeth. Not that it makes too much difference for an N: They're low torque enough with pretty mild starter speeds/torques (especially with a 6V system) that it doesn't really matter. But for higher torque diesels with more potent starter systems, a more even, steady, and slightly lower heat in an oven is better.

Some manuals say to quench immediately once its on to prevent tempering the teeth too much. Some say the opposite: that quenching immediately will embrittle the teeth. Never really worried about that aspect too much myself. I just drop it on and let it cool.

Those temps on those ring gears can make some pretty interesting smells if using the kitchen oven, and the flywheel can really scratch up the kitchen table. Probably best to do when the wife's not home. If you have an oven in your shop, even better.

 

[Hobo,NC]

For pretty much all other ring gears except the N's, you don't even need to get that crazy. It's just the extra step/ridge on the N's that require more heat than typical. Usually you get the ring gear nice and hot in a conventional oven cranked up nice and toasty (450-550 degrees usually does it). Make sure it's been in for long enough for the heat to soak and get the whole thing expanded. Have the flywheel sitting nearby on a solid surface, with the outside free of burrs and cleaned up with no oil/residue on it. A good pair of gloves/tongs to take it out of the oven and drop it on asap, and you're good to go. Not a bad idea to have a brass hammer or mallet handy in case it starts shrinking too fast or gets slightly cockeyed and needs a few gentle taps to get it home before it cools too much, but even that's not typically necessary.

The rosebud/torch heating that's required for the N's is something you want to avoid for other ring gears if possible: The N rings usually need to be heated to 600+ to even have a chance of slipping over, and at those temps you're harming the temper of the teeth. Not that it makes too much difference for an N: They're low torque enough with pretty mild starter speeds/torques (especially with a 6V system) that it doesn't really matter. But for higher torque diesels with more potent starter systems, a more even, steady, and slightly lower heat in an oven is better.

Some manuals say to quench immediately once its on to prevent tempering the teeth too much. Some say the opposite: that quenching immediately will embrittle the teeth. Never really worried about that aspect too much myself. I just drop it on and let it cool.

Those temps on those ring gears can make some pretty interesting smells if using the kitchen oven, and the flywheel can really scratch up the kitchen table. Probably best to do when the wife's not home. If you have an oven in your shop, even better.

I got a stove lets fudge with it till we mess it up its got to be a part issue. That's the problem a shad tree wrench induced the problem.

 

[WilBury]

OK, let's flog this some more...
My manual says 600 degrees, no mention of an oven, no quenching.
Specialty tools Hobo? I wanna pick the right local shop to do it.
Oh, & it'll likely be an aftermarket ring gear.

 

[Hobo,NC]

OK, let's flog this some more...
My manual says 600 degrees, no mention of an oven, no quenching.
Specialty tools Hobo? I wanna pick the right local shop to do it.
Oh, & it'll likely be an aftermarket ring gear.

I snip the old ring gear then drive it off. On a N it takes more than 6 passes no crayons are temp gun needed heat it till its good and blue hot. You need a oxy acetylene setup anything els is a big gamble a oxy acetylene setup is time proven.

 

[DanielW]

When doing them in the field/away from the shop. I just rest the ring on the flywheel, and go around with the O/A torch like Hobo's video shows until it drops on. If doing in the shop, I prefer to use the oven in my shop (which I put there for just that purpose), as that way you know for sure you're not getting any part over 650 degrees (650 degrees(ish) is when you really start to affect the hardness/temper). But ultimately I'd do it whichever way suited me at the time and not worry about it. For a 188, you shouldn't even need to get anywhere near that hot - it'll drop on long before it gets that hot. The N's are the only ones I'd be a little more concerned about - need to have a rosebud ready and do it properly for them. Any method that involves whacking or prying is definitely wrong. Some of the heavy two-stroke Detroits had pretty strong interference fits and hefty flywheels that would suck the heat out of the ring pretty fast, so you'd want to be prepared with a brass hammer or rubber mallet to give it a gentle tap where necessary to seat it. But even that shouldn't be necessary for most ring gears.

For a 188, I wouldn't give it much thought. You could do it with a torch, oven, or BBQ and it'd work out just fine. As long as you get it hot enough to drop on there easily it'll be fine and outlive you.

 

[ASE guy]

OK, let's flog this some more...
My manual says 600 degrees, no mention of an oven, no quenching.
Specialty tools Hobo? I wanna pick the right local shop to do it.
Oh, & it'll likely be an aftermarket ring gear.

Remember, they have a taper. If a machine shop does it, they need to know this.

 

[Hobo,NC]

Tooled up...
You mean a flat table, sheet of asbestos, heavy asbestos gloves, a well supplied rosebud & a temp stick?

All you need is a unlimited heat source (not your kitchen stove) heat it till it drops on a good point to see if it drops on is heat it till it turns a deep dark blue/purple. Once you get the tools ready 5 min. tops no dicking around with heat guns are temp sticks. In the video I posted I grantee he's done 100's he can afford any tool to do this job but he uses a torch. I grantee its never failed him nor me. I happy for those that shake and bake and fool with temp measurements you have one shot to get it right are suffer the consequences.

 

[John P.]

I finally towed the 8N into my shop and yes, the problem is the ring gear is spinning on the flywheel. It looks like gear had been replaced at some time and I'm betting it's an aftermarket brand. The ring gear had been spot welded in a few spots, but those welds were broken, and as the gear spun around the flywheel, the welds cut a groove all the way around the flywheel. I have another flywheel that I dropped off at the machine shop to get ground and have a new New-Holland ring gear installed on.

 

[HarryVanderpool]

A post earlier in this thread suggested using Loctite 640 sleeve and bearing retainer.
How in the world could one do that?
It takes 600 degreesF just to slip over and on.
I doubt ANY glue could survive that.

 

[WilBury]

My new ring gear turned out to be Case/New Hollland for the 188D. Teeth were bevelled for the starter and there was a small bevel in the corner to the flywheel. Had to tap it down a bit after I got it home, hope it's good. Shop used heat & a press. I think he struggled.

 

[John P.]

I took an 8N flywheel and a NAA flywheel off of parts tractors to get re-machined and install new ring gears and pilot bearings (all new New-Holland parts). The 8N flywheel had a lip on it, so the shop machined it off and now it's like any other flywheel.

 

[Hemmjo]

Found this thread while changing the ring gear on my Ford 860 with dual clutch. I am confused by the information in my I & T Shop Manual #FO20.

When I find things that I know are wrong, I begin to question the other information. The manual, clearly says the ring gear comes off the back side (clutch side of the flywheel). My gear is clearly on the front side of the flywheel. (engine side)

My flywheel has a groove as I see mentioned in a few of the previous threads. for 8N's

I have measured my flywheel. The ring has to fit over the 12.024" lip to get to the groove it fits in. Freezing the flywheel to 0˚f makes it 12.018.

I have measured the ID of the ring it is 11.961. The difference in size of 0.063 or 0.057 with the flywheel frozen

I know many say to forget the measurements and just heat is with a torch til it slips on. It must be in excess of 750˚f to expand 0.063". I can do that is necessary, but the manual says not to exceed 450˚f.

My questions;

Is the ring gear correct?

Do I just forget the temperature limit, heat it to 800˚ and be done with it?

My concern is ruining the temper in the gear.

Thanks,

John

EDIT, continuing to research. I have discovered a ring gear at Worthington parts. Also listed at many other sites.

Details state; 134 Teeth, 13.552" OD, 11.994" ID Gasoline. This SHOULD fit on when heated to 400˚, I believe a lot of us are getting bad parts!!

The correct part, according to the specifications, it also available here at YT

 

[Hobo,NC]

Found this thread while changing the ring gear on my Ford 860 with dual clutch. I am confused by the information in my I & T Shop Manual #FO20.

When I find things that I know are wrong, I begin to question the other information. The manual, clearly says the ring gear comes off the back side (clutch side of the flywheel). My gear is clearly on the front side of the flywheel. (engine side)

My flywheel has a groove as I see mentioned in a few of the previous threads. for 8N's

I have measured my flywheel. The ring has to fit over the 12.024" lip to get to the groove it fits in. Freezing the flywheel to 0˚f makes it 12.018.

I have measured the ID of the ring it is 11.961. The difference in size of 0.063 or 0.057 with the flywheel frozen

I know many say to forget the measurements and just heat is with a torch til it slips on. It must be in excess of 750˚f to expand 0.063". I can do that is necessary, but the manual says not to exceed 450˚f.

My questions;

Is the ring gear correct?

Do I just forget the temperature limit, heat it to 800˚ and be done with it?

My concern is ruining the temper in the gear.

Thanks,

John

EDIT, continuing to research. I have discovered a ring gear at Worthington parts. Also listed at many other sites.

Details state; 134 Teeth, 13.552" OD, 11.994" ID Gasoline. This SHOULD fit on when heated to 400˚, I believe a lot of us are getting bad parts!!

The correct part, according to the specifications, it also available here at YT

I provided a video whut izz'it you don't understand.

 

[Tall T]

I, too, am wondering where these ill-fitting ring gears are coming from. I currently have the flywheel off my Case 188D while it is out for repair and the ring gear shows some wear in a few spots so I'm considering replacing it. Has anyone had the same problem with the 188?
If so, I guess I'd better plan on stitch-welding it.

The wear usually occurs on the same short span of teeth because the engine keeps stopping there.
In the past when I had flywheels turned the machinist just repositions the gear and reinstalled it.
The machinist will know if it is tight enough. If your gear was alright to begin with, there's no reason it shouldn't still be after repositioning . . . if done properly as Hobo said.

 

[Hemmjo]

I provided a video whut izz'it you don't understand.

I understand the video perfectly. I am saying that the ring gear I received from a different supplier is not correct. It is advertised to fit most of 4 the cylinder Fords up to 1964. It has ID 11.961" My flywheel is 12.024". That is 0.063" difference. You have to heat that gear to near 800˚f in order to slip it on the flywheel as you clearly show in the video. At the point the gear teeth are ruined and will not last very long in service. If someone is building a show tractor that will sit and look pretty, the gear will last for ever. If the tractor is actually working... I don't want that gear in my tractor.

I was researching the problem when I wrote the first part of that post. I discovered other ring gears on other sites, including this site, that have an ID of 11.994. 12.024 - 11.994 = 0.030 . Heating the gear to a little over 400˚f will expand that gear 0.035" which will allow it to slip easily on the flywheel, as your shows. I edited my post to reflect this new information.

This leads me to believe that many of the issues people have installing rings on the flywheel are related to undersized gears. I have a small machine shop, I could, but should not have to machine the flywheel to install the ring. They should not have to overheat and ruin the gear to install it.

Links;
Incorrect gear

Correct gear

I am always willing to learn if I am wrong. This is the first ring gear I have installed in my 77 years on this rock. But I believe a lot of the problems people have with this procedure is having the wrong part.

 

[Hobo,NC]

I understand the video perfectly. I am saying that the ring gear I received from a different supplier is not correct. It is advertised to fit most of 4 the cylinder Fords up to 1964. It has ID 11.961" My flywheel is 12.024". That is 0.063" difference. You have to heat that gear to near 800˚f in order to slip it on the flywheel as you clearly show in the video. At the point the gear teeth are ruined and will not last very long in service. If someone is building a show tractor that will sit and look pretty, the gear will last for ever. If the tractor is actually working... I don't want that gear in my tractor.

I was researching the problem when I wrote the first part of that post. I discovered other ring gears on other sites, including this site, that have an ID of 11.994. 12.024 - 11.994 = 0.030 . Heating the gear to a little over 400˚f will expand that gear 0.035" which will allow it to slip easily on the flywheel, as your shows. I edited my post to reflect this new information.

This leads me to believe that many of the issues people have installing rings on the flywheel are related to undersized gears. I have a small machine shop, I could, but should not have to machine the flywheel to install the ring. They should not have to overheat and ruin the gear to install it.

Links;
Incorrect gear

Correct gear

I am always willing to learn if I am wrong. This is the first ring gear I have installed in my 77 years on this rock. But I believe a lot of the problems people have with this procedure is having the wrong part.

You could be right about bad parts, in my 52 years of playing mechanic and I could say 56 as I started working in a shop at 14 as a goffer. I never measured a ring gear we broke out the torch and went at it. The shop I started in did truck work so clutch/flywheels were a daily thing. I got well coursed in ring gear replacement we did them just like the video :SHOCK: I have also did a few ford tractors they do require more heat as in 15 passes around the ring gear. I made a post one time and did my best to record the temp it took in the 800 plus range to get the gear to fall on.

I have seen folks/shops fail at this the #1 reason they were not tooled up. They fudge around with insufficient means a Ox/acetylene torch is mandatory. If you don't have the ability to heat it up fast if you heat source is limited you increase the failure rate. Every tractor ring gear install I have seen fail this was the case. I have never see a failure when a ox/ace torch was used nor on this site. They did not have the means to heat it up fast and efficient.

I don't care what the book reads 400 my arse in real life 70 years later with aftermarket close is good enoufh parts it takes 750 to 800 are more. What I don't understand this is a very labor intensive job why take a chance. There is a old X NAPA machine shop in town they take this job on they don't have a torch they fail a lot. Like most they blame it on the part its not the part its installer error. I have never seen gear teeth fail because of to much heat used to install it. 7/800 are 1000 is not going to affect the teeth.