MTFCA Forum

Well I think this is what is called the 4th main, see photo.
I took my hogshead off for a look and to do some repairs see viewtopic.php?f=2&t=22322 if interested.
Anyway I was cleaning up the old gasket on the oil pan today an took all the bolts out of the universal joint because the gasket appeared to be trashed, didn't help as I've sense learned you would need to remove the axle to get at the gasket. Looking around on here and on the web I'm reading about getting the 4th main lined up right are the 4th main and the universal joint the same thing or two different things that make up a unit or is the 4th main something totally different? Just wonder if I may have done something I shouldn't have, don't think so, reading the service manual it says to take all the bolts out the the universal joint to remove the rear axle.
Provided I haven't screwed this up can someone explain how I remove the rear axle so I can change out the universal joint gaskets, I'm not clear on this from reading the service manual, I know how to get the car off the ground, take off the wheels and unbolt the universal joint after that it is unclear to me. I have a 1927 Touring with wire wheels.

I appreciate the help you all have been a wealth of information.

Chapter XIV, Page 147, Paragraphs 547-550 in the Service Manual are what you're looking for.

The U joint slides out with the D/S. The 2 bolts top & bottom are plugs to get access to the U joint pin which is peened in place. (See T1 manual)
The 4 D/s bolts are already out. The 4th main has an oil hole that should be up.(incase you turned it). A new gasket can be in stalled by splitting it at the top. Slide the 4th main back a little to install.

For those who have not yet removed a hog's head:

leave the lower two retaining bolts in the pan and only remove the two upper bolts in the hogshead...this will keep whatever correct or incorrect 4th main alignment intact. The majority of hog's heads can really be removed this way, though you'll find it's easier with the exhaust disconnected and the exhaust manifold removed...this almost always allows the hog's head to be manipulated such that it will tilt up slightly and can be withdrawn upward.
scrape the 1/2 exposed gasket off of the front of the torque tube retainer and the back of the hog's head
do your work on the bands
goop up the hogs head however you feel is appropriate
cut the appropriate gasket in 1/2...you don't need the other half because it's still trapped between the 4th main and the pan.
goop up the torque tube retainer upper 1/2 and the back of the hog's head
stick the gasket into the goop on the torque tube and once the hog's head is in place, massage the gasket into position if it's moved, and it probably has, but not far.

note: goop should be Ultra-Black

if you are a firm believer in the blue silicone snot that is sold at auto parts stores and is the saviour of every hot-rodder in the world, prepare to have your inside oil line and main bearing holes clog up sooner rather than later.

The way I understand your question, you want to replace the gasket between the pan and ball cap. All you need is to get the rear axle back enough to clean off old gasket and slip in a cut new gasket. Loosen the rear shackle bars and back off the nuts but don't remove them, or with L shackles loosen nuts but don't remove. Pull the rear axle back just a little with a come along, about 1/4 inch rearward at the ball cap. Pull ball cap back the 1/4 inch. This should give just enough room to clean off old gasket between pan and ball cap. Cut a new gasket between bolt holes, slip over ball cap and rotate cut to top. A alternate is to cut the gasket in two and place half on top and other half on bottom. Use gasket sealer on lower half of gasket, top half gets sealer when hogshead goes back on. Push rear axle back forward and tighten shackle nuts and replace nut keys. Forgot to say disconnect the hand brake rods, of course reconnect when done.

Do not forget that the two lower bolts are wired together with safety wire.

With any luck at all, and there is still a chance, the 4th main is still stuck to the pan via sealant. If this is the case, the transmission may still be supported.

If the axle is pulled back and the 4th main is liberated from it's seat against the pan, it will most certainly allow the rear of the transmission to sag and no amount of finageling is ever going to find where it really belongs again. The strain will forever be there and induce a small amount of flexing on the rear of the crankshaft which is never a good thing.

When one inherits a car such as this, it is never a safe bet to assume previous work was done correctly, but it is of no benefit to induce problems, either. This is one of those innocuous repairs which really can have much farther reaching ramifications than is obvious at the time. People go to great pains to set up the transmission shaft to run true, and set the 4th main in perfect alignment with the engine pointed nose down and all strain is off of the transmission. Then someone comes along, breaks all of the mechanical fastenings with no thought or care for what the part is supposed to be or at least hopefully, was doing. There really is a reason that folks strongly suggest reviewing the T-1 manual before doing this sort of work.

bmklawt wrote: ↑

Sat Jul 24, 2021 10:00 pm

..... I was cleaning up the old gasket on the oil pan today an took all the bolts out of the universal joint because the gasket appeared to be trashed, didn't help as I've sense learned you would need to remove the axle to get at the gasket.
Looking around on here and on the web I'm reading about getting the 4th main lined up right are the 4th main and the universal joint the same thing or two different things that make up a unit or is the 4th main something totally different? Just wonder if I may have done something I shouldn't have, don't think so, reading the service manual it says to take all the bolts out the the universal joint to remove the rear axle.
....'

This attachment should help you understand what/where things are. The above explanations of replacing the gasket are well explained
This the proper way to wire the two bottom bolts - not as shown in the T picture

I read about having the engine nose down to align the 4th main, how do you keep it aligned you need to have all the bolts out to bolt the driveshaft back on or am I missing something.
I see n the attached photo they have 2 bolts "B" holding the 4th main on when aligning it, I don't get how you keep it aligned.

Think on how far a good transmission can be out of alignment. Drive shaft from the fly wheel is going no where so that leaves 3 bronze bushes to allow for any off alignment, stand the engine on it's noise, slide all the trans together, pan and ball cap. Now lets think on what happens when we lay back down. The weight of the trans as a complete unit will drop onto the drive shaft by only as much as the oil clearance, more so at the flywheel end as a pressured up clutch pack could hold that end central, we are talking about 1/2 a thou. Now the clearance of the babbitt ball cap is .004-.006" For the run out of a transmission to wear or choo out the ball cap will not be the fault of the parts or weight alignment or for assembling lying flat, on it's side or upside down, but who put it together with out checking all the assembly run out on all parts and fixing, which can be a lot.
So fix your gasket, bolt up your ball cap and happy T'"ing!

Assembling the pan to the motor with the pan vertical is meant to preserve the alignment of the pan to the block/transmission assembly. It is a valuable check to see if a pan is bent/out of alignment and needs to be straightened on a pan jig. If the fourth main fits nicely with the motor on the vertical, that is about the best you can do.

That relationship can only be preserved if the fourth main is indexed to the pan while still in the vertical position. I have done this with a pair of roll pins when assembling my speedster.

If the fourth main is not indexed to the pan, it will move a bit, but that cannot be avoided when the motor is turned on the horizontal to be fitted into the car, unless you suspend the car on its nose somehow and fit the motor with the engine vertical. In this situation, there is no relationship to preserve by keeping the fourth main done up. It has already been subject to shift in the motor fitting process. Being able to slide the fourth main back a bit makes it much easier to replace the gasket between the pan and fourth main. If it slides back in, and the bolts can be inserted without interference, that is about the best you can do.

Others may differ.

Allan from down under.

bmklawt wrote: ↑

Sun Jul 25, 2021 2:05 am

I read about having the engine nose down to align the 4th main, how do you keep it aligned you need to have all the bolts out to bolt the driveshaft back on or am I missing something.
I see n the attached photo they have 2 bolts "B" holding the 4th main on when aligning it, I don't get how you keep it aligned.

When attaching pan to motor, 4th main is accurately fitted, (vertically). Dropped on & pan finish bolted on. Pan gaskets ultra black. 4th main removed.
Rotate horizontal. Bands & hogs head installed. Back vertical. 4th main slides on or a bit of hogshead tweeking. All with ultra black. Bolt up 4th main.

MISSING: Before installing engine, remove 4th main BOLTS.
4th main stays where it was set in the vertical position.
Bonus: improved motor. hogs head is attached to the back of the block with shims, if necessary, to maintain that 4th main position.

My Montana 500 buddy pins the 4th main in 2 random spots, so that in a similar situation it goes back in the exact place it was installed.

John, apparently you and I are among the few in the hobby who have had success with this exact same process.

Now, If I was assembling 2 million automobiles per year in my factory, 90 years prior to the advent of any sealant other than shellac, I suppose I would not dial in the transmission TIR, or assemble vertically, or nail down the 4th main in a totally relaxed condition vertically such that when horizontal, the 4th main would continue to support a STRAIGHT assembly rather than a SAGGING assembly.

And If I was assembling 2 million automobiles per year in my factory with the expectation (as originally designed and never updated) that it would be running on dirt roads at about 25 MPH at relatively low RPM then factory methods would be adequate I'd let the transmission sag, too,

We have better products, more time to spend on the assembly, and have an expectation that the engine is going to run 30-40 MPH or more for hours on end on modern paved roads. Time spent getting the best alignment possible, with an unstressed crankshaft, and then MAINTAINING that alignment through the assembly process in the car (due to the adhesive quality of Ultra Black) is not something that is simply dismissed without the occasional unhappy consequence. Lots of people don't care about it and have had success. My mom never wore seatbelts and bragged that she was never thrown through a windshield...who can argue with that? It worked for her.

I am not dismissing the traditional assembly process as wrong, nor condemning anyone who chooses to do it "by the book". I simply believe that in our present world, there are sometimes better ways of doing some things.

Obviously you and I have the same or similar expectations. We are probably (apparently) in the minority.

bmklawt wrote: ↑

Sun Jul 25, 2021 2:05 am

I read about having the engine nose down to align the 4th main, how do you keep it aligned you need to have all the bolts out to bolt the driveshaft back on or am I missing something.
I see n the attached photo they have 2 bolts "B" holding the 4th main on when aligning it, I don't get how you keep it aligned.

IMHO I think you are making a mountain out of a mole hill. And the more you question, the more your likely to screw up.
Since you all you did was unbolt the 4th main and everything else Pan connected to engine and engine connected to chassis there is little chance that anything became misaligned. All you read has to do with an engine rebuild not replacing a gasket.Now if you were to remove the rear axle to get access to the 4th main and it would slide easily in & out it would be properly aligned.
BUT you haven't indicated how the lower half of the 4th main is sealed to the pan. If you haven't disturbed a good seal then put the two bolts back - doubt if anything moved.
Now t hese are instructions for replacing the 4th Main with a bearing style. While your not doing any of that you should be able to relate what you might do if you were to remove the idrive shaft and rear axle http://www.texastparts.com/mm5/manuals/T3369BB+.pdf
NOTE: Only place a gasket behind the 4th Main(engine pan/hogshead side) and don't use one in front, between it and the coupling ring.

speedytinc said "The 4th main has an oil hole that should be up." where is this hole?
I do appreciate all the help, I did originally ask the question because I read a few post of the importance of lining up the 4th main correctly and I suspected the 4th main was at the universal joint but wasn't positive, I get it now.
Someone said a I'm making a "mountain out of a mole hill" I actually enjoy that, learning about the mountain to fix the mole hill, I can be anal and impatient at the same time, like spending 6 hours looking for the correct screws for the dash then paint the car with rattle cans, I did both.

bmklawt wrote: ↑

Sun Jul 25, 2021 10:51 pm

speedytinc said "The 4th main has an oil hole that should be up." where is this hole?
I do appreciate all the help, I did originally ask the question because I read a few post of the importance of lining up the 4th main correctly and I suspected the 4th main was at the universal joint but wasn't positive, I get it now.
Someone said a I'm making a "mountain out of a mole hill" I actually enjoy that, learning about the mountain to fix the mole hill, I can be anal and impatient at the same time, like spending 6 hours looking for the correct screws for the dash then paint the car with rattle cans, I did both.

The oil hole is in the middle of the bearing surface sleeve or tube that the output shaft runs in. You should be able to see it thru the inspection cover.
T1 manual must show it.

Scott, you are not alone in what you do when rebuilding/fitting the fourth main. However in this case, the poster is asking for help with an in-car reassembly, so the finesse you advocate is not/cannot be applied. The whole fitment is being done on the horizontal. In this case the best that can be done is to slip the fourth main in place with the two bottom bolts in place, and use this setting to help position the hogshead as it is fitted. Hopefully the slip fit of the fourth main is still there when the hogshead is bolted down.

Allan from down under.

Here is a picture of the 4th Main also referred to as the Ball Cap- sold thru Lang's https://www.modeltford.com/item/3369.003.aspx

AND I blew up your picture and it appears that the hole is currently in the up position.