help with ring gear ford 8n

[Gary Singleton]

installed a new ring gear on my 8n and not the starter just spins and motor wont turn ,went to my starter and alternator man he said starter was good that the ring gear is slipping its been on for about 4 months no trouble at all starting ,any ideas. does the ring gear go flush with the flywheel where i can see, are to the back toward front of tractor any ideas appreciated i hate to split again

 

[Eman85]

If you have the starter off pry on the ring gear to turn the motor and see if it slips. If you have a timing mark hole look through it while trying to start and see if the ring gear slips.

 

[lha]

installed a new ring gear on my 8n and not the starter just spins and motor wont turn ,went to my starter and alternator man he said starter was good that the ring gear is slipping its been on for about 4 months no trouble at all starting ,any ideas. does the ring gear go flush with the flywheel where i can see, are to the back toward front of tractor any ideas appreciated i hate to split again

When I replaced my clutch and ring gear among other things,the new one spun,so I put some 1' welds at 90 degree spacing. No problems and an easy fix.

 

[JMOR]

When I replaced my clutch and ring gear among other things,the new one spun,so I put some 1' welds at 90 degree spacing. No problems and an easy fix.

https://imgur.com/tbsay09

 

[Gary Singleton]

When I replaced my clutch and ring gear among other things,the new one spun,so I put some 1' welds at 90 degree spacing. No problems and an easy fix.

Thanks that's what my starter man told me to do

 

[Gary Singleton]

When I replaced my clutch and ring gear among other things,the new one spun,so I put some 1' welds at 90 degree spacing. No problems and an easy fix.

Thanks that's what my starter man told me to do

 

[TTOKAR]

https://imgur.com/tbsay09

Anyone drill and tap set screws around -- 5'16 or 1/4?

 

[Dave G9N]

I would like to bump this thread to see if anyone can answer TTOKAR's question about using set screws to stop the ring gear from slipping. I seem to have the same problem with a slipping ring gear.

The instructions in FO-4 say to remove the gear drill a hole and crack it with a chisel. That makes me think that the ring is brittle, so drilling in the wrong place might be a bad idea. Is there a place to drill that is not bad? I was thinking that trying to drill between the gear and flywheel might be safer, but the ID can be a high stress area in some applications.

I could try to weld as recommended, but my welding, for lack of a better word, 'skill', should be limited to things where the initial attempt can be ground off without any serious damage. The weld also makes any later attempt to remove the ring gear difficult.

My 9N starter drive or ring gear has been slipping. It has been starting when the temperature was below 80 degrees in the morning, but barely turned over in the afternoon. The starter motor was turning at a normal sounding speed, but the engine would stop turning after a fraction of a revolution, presumably on a compression stroke. It was apparently a thermal expansion and thermal issue, and I was not aware that the ring gear was a shrink fit.

I just replaced the old style starter drive on my 9N with a new Sparex S.66553 Starter Drive thinking that the starter drive was slipping. Whether that is possible I don't know. The new drive is also slipping, so I searched the forum for a solution. The I didn't know that the ring gear can slip until I found this thread. So before I make any snide remarks about the quality of the new starter drive, I need some advice.

I am considering three possibilities.
1) Weld
2) Set screws
3) Wicking grade Loctite 290.

TOH had suggested the Loctite for securing a piece of hydraulic tubing for rebuilding a a lift cylinder, and this seem to be another place where it mightwork. .

 

[chetswen]

I have had very good results using Loctite 640 sleeve and bearing retainer in simular instances where the fit tolerance is no longer there. The ring gear will have to be removed, parts cleaned, then reassembled for this product to properly work.

 

[Dave G9N]

I have had very good results using Loctite 640 sleeve and bearing retainer in simular instances where the fit tolerance is no longer there.

Thanks, I think that is what Dan had recommended, not 290.

 

[joeysmith]

If i had it apart I would get the flywheel knurled or ping it all around to tighten the fit
Then lock tight on assembly

 

[Jim.ME]

Four tack welds as posted, can be done in place if needed.

You might be able to drill and tap it. The problem can be the drill walking off center especially with the difference in materials of the flywheel and ring gear. Likewise tapping it can be difficult for the same reason.

 

[DanielW]

The set-screw idea would certainly work, but even for you I think it's far more bother than it's worth. Slipping ring gears have been a known problem with N's for decades, and thousands (if not tens of thousands) have been tack-welded by both experienced and amateur welders. And those tractors were (and are) working just dandy. There's no way a couple, evenly-spaced stitches around the flywheel would ever cause issue with balance or running on an N. About every other component of the tractor would have worn out long before a welded ring gear caused issue.

You don't need much skill to weld these. If you're going through the starter hole, just make sure you ground to the crank pulley or a clamp right on the flywheel - you don't want to arc through the bearings. It hardly takes any weld to make these hold. It's not so much the weld itself that makes them hold (the flywheel on the N's is a cast alloy that doesn't take weld too kindly). It's rather the slight distortion of the ring-gear root zone and weld-shrinkage of the ring that causes them to hold.

I totally understand being hesitant if you're completely new to welding. But even if that's the case, it'd still be far easier to have a neighbour or friend who's more experienced come in and apply a few stitches than go to all the trouble of splitting and using retaining compound or machining. If you have any experience at all welding, I'd give it a shot. Worst case, you have to split it to fix a welding boo-boo. But for the set-screw or retaining compound, you'd have to split it anyway. And you'd have to do something pretty atrocious for a weld to be bad enough that you have to split. And if in another 3 of 4 decades the ring gear has to come off again, about 30 seconds with a zip disc would cut the weld and allow it to come off.

I'm a big fan of loc-tite 290 - we used it all the time at the machine shop I worked at where we'd repair a lot of precise news-crew equipment. And I always keep some around for set-screws etc. But even though it's an aerobic compound just like 'proper' retaining compounds, it has pretty low holding power (if comparing it to conventional anaerobic threadlockers, we always considered it comparable to loc-tite 222, which is about as low-strength as you can get). And if your ring gear and flywheel have been contaminated with a little oil at some point over the years, it won't set at all. Even when using it on new fasteners, you have to make sure the fasteners and internal threads are clean with acetone or brake-clean for it to set up properly. You could try it - there's enough surface area at the flywheel-ring junction that it may hold if you slowly wicked it around the entire ring. But that'd be a slow, tedious process that may not work.

 

[John P.]

I’m glad I ran across this thread, this just might be what is wrong with my 8N.

 

[Hobo,NC]

The set-screw idea would certainly work, but even for you I think it's far more bother than it's worth. Slipping ring gears have been a known problem with N's for decades, and thousands (if not tens of thousands) have been tack-welded by both experienced and amateur welders. And those tractors were (and are) working just dandy. There's no way a couple, evenly-spaced stitches around the flywheel would ever cause issue with balance or running on an N. About every other component of the tractor would have worn out long before a welded ring gear caused issue.

You don't need much skill to weld these. If you're going through the starter hole, just make sure you ground to the crank pulley or a clamp right on the flywheel - you don't want to arc through the bearings. It hardly takes any weld to make these hold. It's not so much the weld itself that makes them hold (the flywheel on the N's is a cast alloy that doesn't take weld too kindly). It's rather the slight distortion of the ring-gear root zone and weld-shrinkage of the ring that causes them to hold.

I totally understand being hesitant if you're completely new to welding. But even if that's the case, it'd still be far easier to have a neighbour or friend who's more experienced come in and apply a few stitches than go to all the trouble of splitting and using retaining compound or machining. If you have any experience at all welding, I'd give it a shot. Worst case, you have to split it to fix a welding boo-boo. But for the set-screw or retaining compound, you'd have to split it anyway. And you'd have to do something pretty atrocious for a weld to be bad enough that you have to split. And if in another 3 of 4 decades the ring gear has to come off again, about 30 seconds with a zip disc would cut the weld and allow it to come off.

I'm a big fan of loc-tite 290 - we used it all the time at the machine shop I worked at where we'd repair a lot of precise news-crew equipment. And I always keep some around for set-screws etc. But even though it's an aerobic compound just like 'proper' retaining compounds, it has pretty low holding power (if comparing it to conventional anaerobic threadlockers, we always considered it comparable to loc-tite 222, which is about as low-strength as you can get). And if your ring gear and flywheel have been contaminated with a little oil at some point over the years, it won't set at all. Even when using it on new fasteners, you have to make sure the fasteners and internal threads are clean with acetone or brake-clean for it to set up properly. You could try it - there's enough surface area at the flywheel-ring junction that it may hold if you slowly wicked it around the entire ring. But that'd be a slow, tedious process that may not work.

The only problem I had welding the ring gear to the flywheel was the end of the top starter bolt hit the weld. It had a tap on start up that went away after the engine fired up. A few years later I had to put a starter on it and seen where the top starter bolt was hitting the weld so I ground the end of the bolt off.

 

[HarryVanderpool]

I have never had this problem with my Ns.
So my only comment is that we need to post and track who are selling these oversized ring gears.
This isn't rocket science.
You buy a ring gear for a specific application, (Ns) and they are sized properly.
It's thermal, shrink to fit.
Where are all of these faulty ring gears coming from?
Please post your supplier.

 

[Ultradog MN]

I also recommend welding 4 good tacks.
Can easily be done through the starter hole.
If you don't trust your welding skills and are considering using a locktite product you will need to split the tractor to do that. So split the tractor and bring the flywheel to a welder.
Wouldn't cost much and I would trust the welds more than I would the locktite anyway.
Ns are about the easiest tractor on the planet to split.
If you are in or near the Twin Cities contact me. I would do it for a 6 pack of my favorite beer. Or trailer your tractor here and I'll do it through the starter hole. Same price.

 

[WilBury]

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.

 

[Hobo,NC]

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.

99.99999999999999999% are installer error.

 

[wore out]

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 biggest part of this problem with the little Fords being discussed here is that there's a area of increased diameter of the flywheel that the ring gear has to pass over to get to where it needs to be, then shrink in place on a smaller diameter area.

Lots to go wrong accomplishing that!

Your little CASE has no such inverse step, so installing a new ring gear is not as much of a complicated/critical ordeal.