Topics

Two small projects.

Jim_B
 

As usual MG related. 

During the winter, I have been chasing oil leaks. 
There is a saying about early British cars: “If it does not leak, it's out of oil!” 
One of the larger leaks was a special bolt, in the transmission,  that bolt has a nib on the end and stops the shaft that the cluster gear (Lay shaft in British terms), rides on, from moving. 

This is a basically a special 6mm X 1mm bolt (Top in the picture) but it has a special hex head. The head is the same as you would find on a 1/4” British Standard Fine bolt. 
The nib on the original was worn part way through. I ordered a replacement from one of the usual sources and what I got was a bolt with a metric thread, an 12mm hex and with insufficient threads. The bolt would not bottom on the gearbox casting. Depending on the thickness of the lock washer it might not be locked. In addition it was metric grade 8.8.  Doing a rough file comparison, it was softer than the original bolt.  Since the original was already worn, after (perhaps) 44000 miles, I did not like that. 

I searched other vendors, they appeared to have the same unit.  I contacted the original vendor and expressed my displeasure.  They found me a used one with, they said, some slightly buggered threads. 

While waiting for that to arrive I ordered a die from McMasters, and while I was there a foot of 12 mm Hex 4140 Chrome Moly stock.  The 12 mm hex is slightly larger than the 1/4 BSF 

The die and the 4140 arrived several days before the used bolt, so I decided to make a new, better, and “correct" bolt. 

The Hex was milled down on the lathe.  The turned bolt was held in a QCTP tool holder, with a copper sheet under the bolts (so as not to mark the shaft or threads). The hex was leveled, before tightening, with a small bubble level. and then about 0.015 take off. Process repeated for all six sides. 
The bolt is the bottom one in the top photo. 


That bolt is now in the transmission.

Also this winter I am replacing the rear axles. Nothing wrong, but the original axles have a history of snapping.  So I purchased some after market ones made of “superior” steel. 

To remove the old axles I need an adapter that goes on the slide hammer. 7/8-14 internal threads on one end to fit the axle, 5/8-18 on the other end to fit the slide hammer. 

I had about a foot of 12L14 1-1/4 hex stock. The 7/8 thread was single pointed. I have not single pointed a thread is some time and almost screwed it up. I drilled up to 3/4” by 1” deep and then bored out to the root of the thread. I relieved about 1/4” leaving free room for the threading tool. 
The 5/8 end was tapped. 

 
Nothing sophisticated but just enough to keep me going. 

Jim B.





--
Jim B

Steven Schlegel
 

Nice job!

 

Sent from Mail for Windows 10

 


From: SouthBendLathe@groups.io <SouthBendLathe@groups.io> on behalf of Jim_B <jim@...>
Sent: Tuesday, February 18, 2020 11:01:11 AM
To: SouthBendLathe@groups.io <SouthBendLathe@groups.io>
Subject: [SouthBendLathe] Two small projects.
 
As usual MG related. 

During the winter, I have been chasing oil leaks. 
There is a saying about early British cars: “If it does not leak, it's out of oil!” 
One of the larger leaks was a special bolt, in the transmission,  that bolt has a nib on the end and stops the shaft that the cluster gear (Lay shaft in British terms), rides on, from moving. 

This is a basically a special 6mm X 1mm bolt (Top in the picture) but it has a special hex head. The head is the same as you would find on a 1/4” British Standard Fine bolt. 
The nib on the original was worn part way through. I ordered a replacement from one of the usual sources and what I got was a bolt with a metric thread, an 12mm hex and with insufficient threads. The bolt would not bottom on the gearbox casting. Depending on the thickness of the lock washer it might not be locked. In addition it was metric grade 8.8.  Doing a rough file comparison, it was softer than the original bolt.  Since the original was already worn, after (perhaps) 44000 miles, I did not like that. 

I searched other vendors, they appeared to have the same unit.  I contacted the original vendor and expressed my displeasure.  They found me a used one with, they said, some slightly buggered threads. 

While waiting for that to arrive I ordered a die from McMasters, and while I was there a foot of 12 mm Hex 4140 Chrome Moly stock.  The 12 mm hex is slightly larger than the 1/4 BSF 

The die and the 4140 arrived several days before the used bolt, so I decided to make a new, better, and “correct" bolt. 

The Hex was milled down on the lathe.  The turned bolt was held in a QCTP tool holder, with a copper sheet under the bolts (so as not to mark the shaft or threads). The hex was leveled, before tightening, with a small bubble level. and then about 0.015 take off. Process repeated for all six sides. 
The bolt is the bottom one in the top photo. 


That bolt is now in the transmission.

Also this winter I am replacing the rear axles. Nothing wrong, but the original axles have a history of snapping.  So I purchased some after market ones made of “superior” steel. 

To remove the old axles I need an adapter that goes on the slide hammer. 7/8-14 internal threads on one end to fit the axle, 5/8-18 on the other end to fit the slide hammer. 

I had about a foot of 12L14 1-1/4 hex stock. The 7/8 thread was single pointed. I have not single pointed a thread is some time and almost screwed it up. I drilled up to 3/4” by 1” deep and then bored out to the root of the thread. I relieved about 1/4” leaving free room for the threading tool. 
The 5/8 end was tapped. 

 
Nothing sophisticated but just enough to keep me going. 

Jim B.





--
Jim B

Bill in OKC too
 

Looks like your usual great work, Jim. My only experience with an MG is standing in the seat of my Uncle Jack's MG waving my new pirate sword as he zoomed down the road, when I was about 6. I bet you're going to be reliving many more great memories in yours this year. :)

Bill in OKC

William R. Meyers, MSgt, USAF(Ret.)


A human being should be able to change a diaper, plan an invasion,
butcher a hog, conn a ship, design a building, write a sonnet, balance
accounts, build a wall, set a bone, comfort the dying, take orders,
give orders, cooperate, act alone, solve equations, analyze a new
problem, pitch manure, program a computer, cook a tasty meal, fight
efficiently, die gallantly. Specialization is for insects.
LAZARUS LONG (Robert A. Heinlein)





On Tuesday, February 18, 2020, 01:01:43 PM CST, Jim_B <jim@...> wrote:


As usual MG related. 

During the winter, I have been chasing oil leaks. 
There is a saying about early British cars: “If it does not leak, it's out of oil!” 
One of the larger leaks was a special bolt, in the transmission,  that bolt has a nib on the end and stops the shaft that the cluster gear (Lay shaft in British terms), rides on, from moving. 

This is a basically a special 6mm X 1mm bolt (Top in the picture) but it has a special hex head. The head is the same as you would find on a 1/4” British Standard Fine bolt. 
The nib on the original was worn part way through. I ordered a replacement from one of the usual sources and what I got was a bolt with a metric thread, an 12mm hex and with insufficient threads. The bolt would not bottom on the gearbox casting. Depending on the thickness of the lock washer it might not be locked. In addition it was metric grade 8.8.  Doing a rough file comparison, it was softer than the original bolt.  Since the original was already worn, after (perhaps) 44000 miles, I did not like that. 

I searched other vendors, they appeared to have the same unit.  I contacted the original vendor and expressed my displeasure.  They found me a used one with, they said, some slightly buggered threads. 

While waiting for that to arrive I ordered a die from McMasters, and while I was there a foot of 12 mm Hex 4140 Chrome Moly stock.  The 12 mm hex is slightly larger than the 1/4 BSF 

The die and the 4140 arrived several days before the used bolt, so I decided to make a new, better, and “correct" bolt. 

The Hex was milled down on the lathe.  The turned bolt was held in a QCTP tool holder, with a copper sheet under the bolts (so as not to mark the shaft or threads). The hex was leveled, before tightening, with a small bubble level. and then about 0.015 take off. Process repeated for all six sides. 
The bolt is the bottom one in the top photo. 


That bolt is now in the transmission.

Also this winter I am replacing the rear axles. Nothing wrong, but the original axles have a history of snapping.  So I purchased some after market ones made of “superior” steel. 

To remove the old axles I need an adapter that goes on the slide hammer. 7/8-14 internal threads on one end to fit the axle, 5/8-18 on the other end to fit the slide hammer. 

I had about a foot of 12L14 1-1/4 hex stock. The 7/8 thread was single pointed. I have not single pointed a thread is some time and almost screwed it up. I drilled up to 3/4” by 1” deep and then bored out to the root of the thread. I relieved about 1/4” leaving free room for the threading tool. 
The 5/8 end was tapped. 

 
Nothing sophisticated but just enough to keep me going. 

Jim B.





--
Jim B

Payson
 

Can u explain the slide hammer setup?

Payson

Jim_B
 

Sure.
The New Rear Axles have a 7/8-14 UNF on the end.  The slide hammer has a 5/8-16 UNF. 
The existing axles (I hope) Have the same thread. In order to take the old axle out I need to remove the old axle. Its being held in the housing by the bearing which is a press fit on both the axle and the housing. 
So I need to connect the slide hammer to the axle. 
Below is the axle (black), coupling (goldish), and the slide hammer (silver)..



So I made the coupling. The larger threads were single pointed. 7/8 taps are $$



On Feb 19, 2020, at 4:02 PM, Payson <egreene104@...> wrote:

Can u explain the slide hammer setup?

Payson
_._,_._,_


Jim B.





--
Jim B

Phillip Rankin
 

Nice work Jim.

I have a similar project where I will need to make a unique bolt coming up on my Massey Ferguson rebuild/restoration. I'll try to remember to document, and make a post about it. Waiting on a few parts to come in at the moment.

Payson
 

I understand now.  You had to make an adapter.  The axle has an inside thread for the puller to thread into?  My only experience with old vehicles is my 1960 NSU three speed moped, with the engine disassembled now on my workbench.  I don’t mean to steal your thread, but when I was a kid I had a 1955 De Soto. I worked in the gas station and one day after changing the oil I put it into reverse to back out of the bay, the shift was on the dashboard, and I heard a clink and saw the speedometer run up to 10 to 15 mph but we weren’t going anywhere.  The left rear axle broke in half in the middle, and we weren’t going anywhere. To take it out the mechanic pulled everything off, all the brake parts and maybe the backing plate, attached the drum leaving the bolts loose, and banged the drum back-and-forth in and out until the bearing pulled out of the rear axle assembly. I think there was a clip of some sort in the differential to hold the axle in there, because I remember we took the cover off and then it was easy, he took a radiator hose the right diameter and shoved it in the banjo to grab the broken segment and pulled it right out. Then a quick trip to the junkyard in Dorchester Mills Boston. End of story. 
Payson

Jim_B
 

Yes; that’s basically the process I need to go through. On both sides. 
No internal clip though. 

-8
Jim B,

On Feb 20, 2020, at 1:40 PM, Payson via Groups.Io <egreene104@...> wrote:

I understand now. . To take it out the mechanic pulled everything off, all the brake parts and maybe the backing plate, attached the drum leaving the bolts loose, and banged the drum back-and-forth in and out until the bearing pulled out of the rear axle assembly. I think there was a clip of some sort in the differential to hold the axle in there, because I remember we took the cover off and then it was easy, he took a radiator hose the right diameter and shoved it in the banjo to grab the broken segment and pulled it right out. Then a quick trip to the junkyard in Dorchester Mills Boston. End of story. 
Payson

--
Jim B