Let's talk Ring and Pinions

[Drew.Styduhar]

Hey guys,

This is going to get sort of technical so bear with me

Carrier Preload

I went to install the left trumpet housing (right side was never removed) but could not remember if there was previously a gasket or just RTV....or both! The ring and pinion had been replaced some time ago by a tractor shop and I had to put the project on hold for a month to focus on something else so it's not fresh in my mind and all the mess was vacuumed up long ago. I could visibly see some places where rtv was used and bulged out but it was only in select spots near the bolts so maybe just to seal through holes in the casting?

I understand the gasket (.007" thick) is critical in setting the carrier bearing preload (spec is .010-.015) and after debating things for a while, I just decided to try and check things myself. As we all know, just because something was repaired at a shop doesn't mean it was done RIGHT. I guess its possible to set up carrier preload without the gasket, right? Its also possible they just put on a new R&P and put it all back together without checking ANYTHING.

As a rough check, I set up a dial indicator at the top (top cover is off) to measure the carrier side movement best I could. Yes, the pinion is still installed. You can't get a straight shot on the ring gear with the dial indicator so the pointer is at an angle, unfortunately. I put three .020" feeler gauges evenly spaced between the trumpet and axle housing and tightening down the corresponding bolts.

.020 feeler as shims = ~.007 repeatable side to side carrier movement. Prob closer to .010 since indicator is at an angle.​

.007 feeler as shims (simulate gasket) = no side-to-side carrier movement​

​

no shim at all = no side-to-side carrier movement​

Again, I know I'm roughing it here but here's what I'm thinking:

.020 feeler and no gasket (RTV only) would prob put the preload around .010 or so (.020 shim -.010 freeplay). This assumes compressed rtv thickness is basically nothing.​

​

.020 feeler AND gasket would put the preload around .003 (.020 shim - .010 -.007 gasket). Not enough preload.​

I'm not sure what the community feeling is on trumpet gaskets vs RTV only?

As much as I just want to move forward and slam this back together with RTV only my gut feeling is I need to shim the right-side cup to compensate for the left side gasket thickness and add the gasket back in for proper install. Thoughts?

Thanks,

Drew

 

[John Deere D]

Hey guys,

This is going to get sort of technical so bear with me

Carrier Preload

I went to install the left trumpet housing (right side was never removed) but could not remember if there was previously a gasket or just RTV....or both! The ring and pinion had been replaced some time ago by a tractor shop and I had to put the project on hold for a month to focus on something else so it's not fresh in my mind and all the mess was vacuumed up long ago. I could visibly see some places where rtv was used and bulged out but it was only in select spots near the bolts so maybe just to seal through holes in the casting?

I understand the gasket (.007" thick) is critical in setting the carrier bearing preload (spec is .010-.015) and after debating things for a while, I just decided to try and check things myself. As we all know, just because something was repaired at a shop doesn't mean it was done RIGHT. I guess its possible to set up carrier preload without the gasket, right? Its also possible they just put on a new R&P and put it all back together without checking ANYTHING.

As a rough check, I set up a dial indicator at the top (top cover is off) to measure the carrier side movement best I could. Yes, the pinion is still installed. You can't get a straight shot on the ring gear with the dial indicator so the pointer is at an angle, unfortunately. I put three .020" feeler gauges evenly spaced between the trumpet and axle housing and tightening down the corresponding bolts.

.020 feeler as shims = ~.007 repeatable side to side carrier movement. Prob closer to .010 since indicator is at an angle.​

.007 feeler as shims (simulate gasket) = no side-to-side carrier movement​

​

no shim at all = no side-to-side carrier movement​

Again, I know I'm roughing it here but here's what I'm thinking:

.020 feeler and no gasket (RTV only) would prob put the preload around .010 or so (.020 shim -.010 freeplay). This assumes compressed rtv thickness is basically nothing.​

​

.020 feeler AND gasket would put the preload around .003 (.020 shim - .010 -.007 gasket). Not enough preload.​

I'm not sure what the community feeling is on trumpet gaskets vs RTV only?

As much as I just want to move forward and slam this back together with RTV only my gut feeling is I need to shim the right-side cup to compensate for the left side gasket thickness and add the gasket back in for proper install. Thoughts?

Thanks,

Drew

I've read your post several times.
Could you please indicate the Make Model of your Tractor?
I'm unable to see clearly, if this Tractor was operating properly,and you have decided to check the previous work quality? or,if there is a problem,thus, the trumpet is presently removed?
Any MF 35's or Ford N"s that I have been involved with,I have always installed a new Gasket,never RTV.

Bob..

 

[Drew.Styduhar]

Sorry, I thought the make and model is listed under my name. Can folks not see it? 1978 Massey 20C.

The tractor was working properly but the left side trumpet was leaking. I was informed by previous owner that the ring and pinion was replaced sometime in the 90's. They gave me shop documentation, but that shop is no longer in business.

Also, I found that the trumped housing bolts has loosened up. Tried tightening things up but the damage had been done. I looked closely for any stress cracks and dont see anything. I think thats maybe more of an issue with Fords since they use studs only?

Thanks,

Drew

 

[Jim.ME]

I guess I am not the only thick person here. Because you posted this in a past thread when I asked the same thing, I knew you expect everyone to know it is the MF 20C you have in your avatar under your username. You have to realize many people work on a tractor other than the one in their avatar and some have been bit by that in the past by answering about the poster's avatar tractor, only to find out it was not the one in question. I just think it is best to add the tractor info in the first post of a thread you start, if you want to avoid being asked.

 

[Drew.Styduhar]

Understood. Sorry for the confusion. I was going to edit the first post to include tractor info but looks like after a certain time expires, the edit option disappears.

 

[Jim.ME]

Understood. Sorry for the confusion. I was going to edit the first post to include tractor info but looks like after a certain time expires, the edit option disappears.

I believe the Edit feature has a 24-hour time limit.

 

[John Deere D]

Sorry, I thought the make and model is listed under my name. Can folks not see it? 1978 Massey 20C.

The tractor was working properly but the left side trumpet was leaking. I was informed by previous owner that the ring and pinion was replaced sometime in the 90's. They gave me shop documentation, but that shop is no longer in business.

Also, I found that the trumped housing bolts has loosened up. Tried tightening things up but the damage had been done. I looked closely for any stress cracks and dont see anything. I think thats maybe more of an issue with Fords since they use studs only?

Thanks,

Drew do with my prefernce o

My Avatar is only a picture,not make and or color specific of anything I'm promoting. On another post,the contributor calls his Tractor BUSTER what is a Buster, thus it lets a dim light in to the lack of proper terminology,consequently stifling both productive input as well as out come.

Relief Chief,Natural Gas Industry:
Now Retired:
Bob...

 

[Drew.Styduhar]

So gents, any thoughts on my situation?

I want to dive deeper into a gear pattern and pinion depth discussion but dont want to waste anyone's time if this is the wrong venue for that type of discussion. Please advise if there's a more appropriate forum for drivetrain/axle questions.

Thank you!

Drew

 

[Jim.ME]

As to using the gasket or RTV, I go by the parts book. The 20C book shows trumpet gaskets are OEM, they would go back in. I would shim the bearing cup(s). The pinion needs to be clear of the ring gear to avoid it skewing movement. It sounds like you need some of the attachments for your indicator that will give "square" contact with the ring gear to get proper measurements. Trying to get readings on an angle often causes indicator point to slide and mounting arm movement that is not measured and give incorrect readings. Just my thoughts, others may vary.

 

[miangus]

I do not believe removing the trumpet impacts the ring and pinion adjustment. If you want to check the previous work on the ring and pinion you can do that by watching the pinion run on the ring gear as you rotate it. Put some grease on the face of the ring gear and watch how it behaves.

 

[Tom from Buckeye Lake]

Hey guys,

This is going to get sort of technical so bear with me

Carrier Preload

I went to install the left trumpet housing (right side was never removed) but could not remember if there was previously a gasket or just RTV....or both! The ring and pinion had been replaced some time ago by a tractor shop and I had to put the project on hold for a month to focus on something else so it's not fresh in my mind and all the mess was vacuumed up long ago. I could visibly see some places where rtv was used and bulged out but it was only in select spots near the bolts so maybe just to seal through holes in the casting?

I understand the gasket (.007" thick) is critical in setting the carrier bearing preload (spec is .010-.015) and after debating things for a while, I just decided to try and check things myself. As we all know, just because something was repaired at a shop doesn't mean it was done RIGHT. I guess its possible to set up carrier preload without the gasket, right? Its also possible they just put on a new R&P and put it all back together without checking ANYTHING.

As a rough check, I set up a dial indicator at the top (top cover is off) to measure the carrier side movement best I could. Yes, the pinion is still installed. You can't get a straight shot on the ring gear with the dial indicator so the pointer is at an angle, unfortunately. I put three .020" feeler gauges evenly spaced between the trumpet and axle housing and tightening down the corresponding bolts.

.020 feeler as shims = ~.007 repeatable side to side carrier movement. Prob closer to .010 since indicator is at an angle.​

.007 feeler as shims (simulate gasket) = no side-to-side carrier movement​

​

no shim at all = no side-to-side carrier movement​

Again, I know I'm roughing it here but here's what I'm thinking:

.020 feeler and no gasket (RTV only) would prob put the preload around .010 or so (.020 shim -.010 freeplay). This assumes compressed rtv thickness is basically nothing.​

​

.020 feeler AND gasket would put the preload around .003 (.020 shim - .010 -.007 gasket). Not enough preload.​

I'm not sure what the community feeling is on trumpet gaskets vs RTV only?

As much as I just want to move forward and slam this back together with RTV only my gut feeling is I need to shim the right-side cup to compensate for the left side gasket thickness and add the gasket back in for proper install. Thoughts?

Thanks,

Drew

I have these from my Machinist days. Starrett No. 671 attachment set. Makes measurements easier in tight places.

 

[Drew.Styduhar]

I have these from my Machinist days. Starrett No. 671 attachment set. Makes measurements easier in tight places.

Thanks Tom, Ive seen those old attachments before.....They look neat! I was using a removable tips with fixed angles on them to minimize any scrub. Looks like they also sell indicators with a sweep tip at the end that might be more affordable for me. Thanks!!

 

[Drew.Styduhar]

I do not believe removing the trumpet impacts the ring and pinion adjustment. If you want to check the previous work on the ring and pinion you can do that by watching the pinion run on the ring gear as you rotate it. Put some grease on the face of the ring gear and watch how it behaves.

Bolting up the trumpet without any shims and checking pattern was my next step. Plan to do that tonight and share the findings.

I've been looking at the service manual (and videos online) and don't see any mention of shimming the pinion for depth on these old Massey's

Just a quick glance shows the pinion depth as way too shallow. Will report back when I have a mesh pattern to share.

Thanks,

Drew

 

[Drew.Styduhar]

As to using the gasket or RTV, I go by the parts book. The 20C book shows trumpet gaskets are OEM, they would go back in. I would shim the bearing cup(s). The pinion needs to be clear of the ring gear to avoid it skewing movement. It sounds like you need some of the attachments for your indicator that will give "square" contact with the ring gear to get proper measurements. Trying to get readings on an angle often causes indicator point to slide and mounting arm movement that is not measured and give incorrect readings. Just my thoughts, others may vary.

Appreciate the input. Thats my gut feel on the gasket too. My gut feel is also that the shop just slammed in a new gear set and didnt check/change anything but who knows.

I guess my goal here is to find a point where there is no carrier movement, pattern makes sense and then preload accordingly. So long as the carrier/pinion is not loaded in coast or drive, I think the measurement is legit and I can sneak up on this via shims between the trumpet and housing. Need to figure out if the pinion depth is adjustable first though as that would precede backlash and preload.

BTW, I'm using an angled tip on the indicator to prevent scrub.

Thanks,

Drew