Mike's A727 Rebuild

[RockwoodMike]

Hello Everyone!! Another A727 rebuild in the works here..I have torn it down in my other thread, but I am going to get into the details of it all here..

So here goes..........

Pic 1..Here is my assemble table..This is the same area that I rebuilt the rearend of my D22 1973 Indian..
Simple 2 saw horses, a piece of 1/4 plate steel and some cardboard..Cardboard acts like a sponge if you have trans fluid leak from somewhere..

Pic 2.. 90 degree view from the first pic showing the tool box for easy reach.

Pic 3..One of the 3/8 bolts that hold the tail housing has blown out threads in the case..3/8 Helicoil kit on order..Be here on Saturday to fix it..

Pic 4..Take out these 3 plugs..They are access points for pressure gauges..I didn't have them out when I was soda blasting and soda was in the passages..That would have been bad!!
Another washing with the power washer was done..

[RockwoodMike]

Another thing I needed to do before power washing it again was to take out the low reverse servo mechanism..(for lack of a better name)..Long punch (I used a long 3/8 ratchet extension..One tap and it push right out) This needs to come out to clean everything well and to later replace the sealing O ring that is on the shaft..

All shafts need to be sealed to keep them from leaking...Right?    

[RockwoodMike]

The bell housing is round and I nearly had the case fall off the table because of it..That would have not been good..So I came up with this...

Pic 1 and 2..A simple 2x2 about 18 inches long bolted at the top 2 bolt holes of the bell housing..Stop it from rolling and hold it steady...

Pic 3...Bell housing face down with another 2x2 and it stays in place..

Pic 4...With 3 2x6 locks under the body area, it holds steady when you are working on it..

[RockwoodMike]

Using this tool...

https://www.ebay.com/itm/154387238108

On the rear clutch..This is the clutch that creates 2nd and 3rd gear..

With the clutch engaged..3rd gear
with the clutch disengaged..and the forward band on..second gear..

With the tool in use, you push down on the spring retainer plate..remove the circlip and loosen the tool..and all the springs showing..Yours springs and arrangement might be different

Pics show the steps

[RockwoodMike]

Steel and frictions from this clutch..Notice the pattern on the frictions..Cross hatch..

The other clutch has smooth frictions..

Pic 1..Smoked steel..Burnt and warped

Pic 2.. Frictions..Totally smoked..

The heavy pressure plate at the top of the stack is in good shape..Not cracked or burnt

[RockwoodMike]

Center of this clutch area..

This bushing looks good..You can see the area where the rings ride on..That area will be green scotch pad smooth..So when the new rings will have seat to the cross hatch the pad will do..
Like doing a hone on a engine cylinder so the piston rings seat and seal properly..

Pic 2..shows the rubber lip seals..The inner seal was flat and this may be the reason for the clutch being burnt..Just leaked all the pressure out and caused a weak engagement

Pic 3..Blown out pan bolt thread..just one of them is bad..5/16-18 Helicoil  needed..

[RockwoodMike]

Rear clutch assemble..This clutch is on in all forward gears and stays on..

So you put the shift selector in drive..shift through all the gears as you accelerate..It is on all through the shifting..

Only off in park-neutral and reverse..

Pic 1..Shows the clutch with the steels and frictions removed..Bellville spring showing..along with the piston and that little thrust washer..That is the washer that has both the input shaft and output shaft meeting in the middle..

Pic 2..Frictions are made with a smooth pattern because it is just made to hold constantly through the shift pattern..They got very warm..make that hot!!

Pic 3..Steels were in fair shape..will be replaced.

Pic 4..the top thick steel plate is fine..be used again after scotch pad is used on it

[RockwoodMike]

You have 2 snap rings in this clutch..1 to hold the friction steel stack in place and a wavy snap ring to hold the bellville spring and piston in..They are made very different from each other..

Pic 1..Wavy ring on the left..for the bellville spring..A bit of work to get it out and more work to get it back in later..Smooth ring on the right is to hold the clutch stack in place..

Pic 2..plastic spacer..they use to make them from steel..hard to find those..Plastic can melt..Mine checked out okay and will be reused.

Pic 3..Belleville spring..This is the weaker spring replaced in 1975 with a stronger spring..You must have the matching piston to the spring..The later spring uses a taller piston..
Piston and spring must go together

Pic 4..Once the spring is out, it becomes 2 pieces for the input shaft..Just look everything over for any wear

[RockwoodMike]

Pic 1..Backside of the piston..Check ball needs to rattle clean..That is the ball that bleeds the pressure off of the clutch when you shift from drive into park..If the ball is plugged. the clutch will be on still ..not good for the clutch..

Pic 2..Front of the piston..seals removed..they were hard and flat..not sealing well..What do you expect after 50 years??

[RockwoodMike]

Output planetary gear set..

Pic 1..Check the spline fit..they are known to strip out or loosen up..smooth tight fit needed..

Pic 2..splines are fine and sharp

Pic 3...back side of the annular ring..where the thrust washer is up against..Smooth and good..

Pic 4...Front thrust washer looks to need help..worn down good..

[RockwoodMike]

Pic 1..This is the other planetary gear set..Thrust washer on this needs to be replaced..Check the 4 planet gears for wear, looseness, anything that looks bad..

Other than the thrust washer, it is in good shape

Pic 2..Thrust washer between planets and ring gear..The racers will machine this area to accept a torrington bearing to eliminate the thrust washer for less friction..
There is so many things you can do on these transmissions..How much money do you have to spend??

[RockwoodMike]

Pic 1..Stater support shaft..The stater is in the torque convertor..This support is splined..check the splines for wear...Also has the original factory seal with the Chrysler emblem stamped in it..Not bad for 50 years!!

Pic 2..The oil tells a story of the condition of it..A small amount of burning with the oil

Pic 3..Pump has a paper gasket and this rubber ring to seal it to the case..

[RockwoodMike]

Checking inside the pump gear area..

Pic 1..I think these little slits(shown in red) are for lubrication..

Pic 2..Gears..The inner gear has a bevel on the inside..Must be installed like this..Other side of this gear is flat..Need to check clearances with feeler gauges..Easy to find and replace if necessary..

Pic 3..Inside the area where the gears spin..Smooth and clean..I Like It!!

That is all for now..

[RockwoodMike]

Time to fix the blown out thread..this is 1 of 6 bolts that hold the tail housing on..I figured out how it got blown out..

Pic 1 shows the hole with the bad thread..3/8-16 size

Pic 2 Helicoil kit to fix it..Doesn't come with the drill bit needed..but everything else..

Pic 3  Shows the hole after drilling it out for the tap..

Pic 4  Put some grease on the end of the tap..taps easier and the cuttings will stick to the tap to clear out the hole..Still need to use compressed air to completely clear it all out..

[RockwoodMike]

Pic 1..Insert ready to be threaded in with the included tool.

Pic 2..After the install..These Helicoil kits really work well.

Pic 3...How it got blown out..?? The hole that was bad is the only that does not thread into the inner part of the case..In other words it has a bottom to it..

There are 2 different lengths of bolts for the 6 bolts..Someone screwed a long bolt into a short bottom hole.. and just kept torque it till it ripped the threads out..

I have one of the threaded holes for the pan to fix too..But it is 5/16..kit is on the way

[RockwoodMike]

Received my rebuilt torque convertor today
Company wanted the core back and sent a label to do it ..On it's way back to Florida!!

[RockwoodMike]

https://www.ebay.com/itm/193234410419

Pic 1..I bought this kit off Ebay All SAE sizes..1/4..5/16..3/8..7/16..1/2 sizes  Has the drill bit, tap and inserts for all sizes..Bought it for the 5/16 size as one of my pan bolt threads was blown out..

Pic 2..Blown hole..No threads at all

Pic 3..After drilling with included drill bit and tap..Ready for the insert.

Pic 4..After the insert was inserted..Good or better than new..

[RockwoodMike]

I am still waiting on my kit..I am going all out on this rebuild..I will be doing plenty of hill climbing and I need a transmission that I can climb a tree with and not break a sweat..

Pic 1..At the rear of the case, inside, is the low reverse sprag ..It's job is to hold the rear drum from spinning counter clockwise..That is what is needed to create first gear(low)..Along with the forward drum to be locked up on the clutches..This sprag has to be strong on a super heavy motorhome starting from a dead stop..
Stock has 12 roller bearings and is pressed into the case..The picture shows where the sprag was after punching it out..

Pic 2..This is the original sprag on the bench..

Pic 3..Here is the rear support..It supports the output shaft as it passes through the case to the tail housing..It also holds the rear drum and sprag in place..

As the fluid comes back from the cooler, it dumps into the case right at all of this sprag and support..

The sprag can be slightly drill larger for its oil port and I made this slot all around the perimeter to get oil to do a better job of keeping everything wet with cool oil..

If your oil cooler quits and gets plugged up, it will destroy everything just mentioned..

[RockwoodMike]

Here is a great video on the function and replacement of the better sprag

[RockwoodMike]

Trans kit arrived  

[RockwoodMike]

Pic 1..Rebuilt 2nd band and low reverse band(little one)

Pic 2..16 roller sprag..Bolted and pressed into the case..MUCH stronger..First gear needs to be strong to get you rolling..

Pic 3..Deep oil pan..I think it adds 3 quarts..Comes with a filter extension to reach the bottom of the pan..Using the original dip stick.

Pic 4 ..Full gasket kit

[RockwoodMike]

Pic 1..Full set of thrust washers..Also I high leverage lever for second gear..4.2 ratio..The stock one I have is 3.8..I have feeling that I will use the 3.8 again

Pic 2..Stud and nut kit for mounting the pan..No more striped threads and the heavy duty strut set up for the second gear band..


Pic 3..Full bushing set..I am not going to replace all of them..Problem is having the right bushing driver to install..

[RockwoodMike]

heavy duty clutches and steels..Came with 9 clutches and 8 steels..Should be able to add an extra clutch to the 3rd gear pack ..to have 5..up from 4..much more holding power

Time to start building it!!

[Mlw]

You probably will but just in case, also go for a new torque converter.

I'm pretty convinced all the glitter I found was from the torque converter because all the gears and parts in the transmission after the filter looked brandnew and no sludge or metal particals whatsoever.

So I'm going to take it a little easier than you do. Thought about the deeper pan too but as everything looks fine it thought against it. I am going to add a pressure meter and temperature meter to the dash.

[RockwoodMike]

https://www.ebay.com/itm/252461716451

Hi MLW,

I feel bad for showing this "E" word listing, but I couldn't beat it..That price has a 100 dollar core refundable on it..So total of 329..The convertor had a postage paid UPS label included in the box..

So I just boxed up the old one, slapped the label on and off it went..

Looking at the description of the rebuild and their feedback..Looked like a fair deal..

Back at post 15, i mentioned receiving it..Here is a repost of it side by side with the old one..